Bug 1470125 - Update webrender to commit cdfaaeb5f74e416f39af1081c9a676c752d23896. r=Gankro

Includes regenerated webrender_ffi_generated.h header.

MozReview-Commit-ID: I3lvkCH5IGz

--HG--
extra : rebase_source : 654102de6773960af67069e7e4c2b27474d9a04c

gfx/webrender/Cargo.toml

@@ -27,12 +27,12 @@ cfg-if = "0.1.2"
 euclid = "0.17.3"
 fxhash = "0.2.1"
 gleam = "0.5"
-image = { optional = true, version = "0.18" }
+image = { optional = true, version = "0.19" }
 lazy_static = "1"
 log = "0.4"
 num-traits = "0.1.43"
 plane-split = "0.9.1"
-png = { optional = true, version = "0.11" }
+png = { optional = true, version = "0.12" }
 rayon = "1"
 ron = { optional = true, version = "0.1.7" }
 serde = { optional = true, version = "1.0", features = ["serde_derive"] }

gfx/webrender/res/brush.glsl

@@ -16,7 +16,6 @@ void brush_vs(
     vec4 segment_data
 );
 
-#define VECS_PER_BRUSH_PRIM                 2
 #define VECS_PER_SEGMENT                    2
 
 #define BRUSH_FLAG_PERSPECTIVE_INTERPOLATION    1
@@ -24,76 +23,19 @@ void brush_vs(
 #define BRUSH_FLAG_SEGMENT_REPEAT_X             4
 #define BRUSH_FLAG_SEGMENT_REPEAT_Y             8
 
-//Note: these have to match `gpu_types` constants
-#define INT_BITS    (31)
-#define CLIP_CHAIN_RECT_BITS    (22)
-#define SEGMENT_BITS (INT_BITS - CLIP_CHAIN_RECT_BITS)
-#define EDGE_FLAG_BITS (4)
-#define BRUSH_FLAG_BITS (4)
-#define CLIP_SCROLL_INDEX_BITS (INT_BITS - EDGE_FLAG_BITS - BRUSH_FLAG_BITS)
-
-struct BrushInstance {
-    int picture_address;
-    int prim_address;
-    int clip_chain_rect_index;
-    int scroll_node_id;
-    int clip_address;
-    int z;
-    int segment_index;
-    int edge_mask;
-    int flags;
-    ivec3 user_data;
-};
-
-BrushInstance load_brush() {
-    BrushInstance bi;
-
-    bi.picture_address = aData0.x & 0xffff;
-    bi.clip_address = aData0.x >> 16;
-    bi.prim_address = aData0.y;
-    bi.clip_chain_rect_index = aData0.z  & ((1 << CLIP_CHAIN_RECT_BITS) - 1);
-    bi.segment_index = aData0.z >> CLIP_CHAIN_RECT_BITS;
-    bi.z = aData0.w;
-    bi.scroll_node_id = aData1.x & ((1 << CLIP_SCROLL_INDEX_BITS) - 1);
-    bi.edge_mask = (aData1.x >> CLIP_SCROLL_INDEX_BITS) & 0xf;
-    bi.flags = (aData1.x >> (CLIP_SCROLL_INDEX_BITS + EDGE_FLAG_BITS)) & 0xf;
-    bi.user_data = aData1.yzw;
-
-    return bi;
-}
-
-struct BrushPrimitive {
-    RectWithSize local_rect;
-    RectWithSize local_clip_rect;
-};
-
-BrushPrimitive fetch_brush_primitive(int address, int clip_chain_rect_index) {
-    vec4 data[2] = fetch_from_resource_cache_2(address);
-
-    RectWithSize clip_chain_rect = fetch_clip_chain_rect(clip_chain_rect_index);
-    RectWithSize brush_clip_rect = RectWithSize(data[1].xy, data[1].zw);
-    RectWithSize clip_rect = intersect_rects(clip_chain_rect, brush_clip_rect);
-
-    BrushPrimitive prim = BrushPrimitive(RectWithSize(data[0].xy, data[0].zw), clip_rect);
-
-    return prim;
-}
-
 void main(void) {
     // Load the brush instance from vertex attributes.
-    BrushInstance brush = load_brush();
-
-    // Load the geometry for this brush. For now, this is simply the
-    // local rect of the primitive. In the future, this will support
-    // loading segment rects, and other rect formats (glyphs).
-    BrushPrimitive brush_prim =
-        fetch_brush_primitive(brush.prim_address, brush.clip_chain_rect_index);
+    int prim_header_address = aData.x;
+    int clip_address = aData.y;
+    int segment_index = aData.z & 0xffff;
+    int edge_flags = (aData.z >> 16) & 0xff;
+    int brush_flags = (aData.z >> 24) & 0xff;
+    PrimitiveHeader ph = fetch_prim_header(prim_header_address);
 
     // Fetch the segment of this brush primitive we are drawing.
-    int segment_address = brush.prim_address +
-                          VECS_PER_BRUSH_PRIM +
+    int segment_address = ph.specific_prim_address +
                           VECS_PER_SPECIFIC_BRUSH +
-                          brush.segment_index * VECS_PER_SEGMENT;
+                          segment_index * VECS_PER_SEGMENT;
 
     vec4[2] segment_data = fetch_from_resource_cache_2(segment_address);
     RectWithSize local_segment_rect = RectWithSize(segment_data[0].xy, segment_data[0].zw);
@@ -101,20 +43,20 @@ void main(void) {
     VertexInfo vi;
 
     // Fetch the dynamic picture that we are drawing on.
-    PictureTask pic_task = fetch_picture_task(brush.picture_address);
-    ClipArea clip_area = fetch_clip_area(brush.clip_address);
+    PictureTask pic_task = fetch_picture_task(ph.render_task_index);
+    ClipArea clip_area = fetch_clip_area(clip_address);
 
-    ClipScrollNode scroll_node = fetch_clip_scroll_node(brush.scroll_node_id);
+    Transform transform = fetch_transform(ph.transform_id);
 
     // Write the normal vertex information out.
-    if (scroll_node.is_axis_aligned) {
+    if (transform.is_axis_aligned) {
         vi = write_vertex(
             local_segment_rect,
-            brush_prim.local_clip_rect,
-            float(brush.z),
-            scroll_node,
+            ph.local_clip_rect,
+            ph.z,
+            transform,
             pic_task,
-            brush_prim.local_rect
+            ph.local_rect
         );
 
         // TODO(gw): transform bounds may be referenced by
@@ -127,16 +69,16 @@ void main(void) {
         init_transform_vs(vec4(vec2(-1000000.0), vec2(1000000.0)));
 #endif
     } else {
-        bvec4 edge_mask = notEqual(brush.edge_mask & ivec4(1, 2, 4, 8), ivec4(0));
-        bool do_perspective_interpolation = (brush.flags & BRUSH_FLAG_PERSPECTIVE_INTERPOLATION) != 0;
+        bvec4 edge_mask = notEqual(edge_flags & ivec4(1, 2, 4, 8), ivec4(0));
+        bool do_perspective_interpolation = (brush_flags & BRUSH_FLAG_PERSPECTIVE_INTERPOLATION) != 0;
 
         vi = write_transform_vertex(
             local_segment_rect,
-            brush_prim.local_rect,
-            brush_prim.local_clip_rect,
+            ph.local_rect,
+            ph.local_clip_rect,
             mix(vec4(0.0), vec4(1.0), edge_mask),
-            float(brush.z),
-            scroll_node,
+            ph.z,
+            transform,
             pic_task,
             do_perspective_interpolation
         );
@@ -158,13 +100,13 @@ void main(void) {
     // Run the specific brush VS code to write interpolators.
     brush_vs(
         vi,
-        brush.prim_address + VECS_PER_BRUSH_PRIM,
-        brush_prim.local_rect,
+        ph.specific_prim_address,
+        ph.local_rect,
         local_segment_rect,
-        brush.user_data,
-        scroll_node.transform,
+        ph.user_data,
+        transform.m,
         pic_task,
-        brush.flags,
+        brush_flags,
         segment_data[1]
     );
 }

gfx/webrender/res/brush_linear_gradient.glsl

@@ -49,11 +49,16 @@ void brush_vs(
     mat4 transform,
     PictureTask pic_task,
     int brush_flags,
-    vec4 unused
+    vec4 texel_rect
 ) {
     Gradient gradient = fetch_gradient(prim_address);
 
-    vPos = vi.local_pos - local_rect.p0;
+    if ((brush_flags & BRUSH_FLAG_SEGMENT_RELATIVE) != 0) {
+        vPos = (vi.local_pos - segment_rect.p0) / segment_rect.size;
+        vPos = vPos * (texel_rect.zw - texel_rect.xy) + texel_rect.xy;
+    } else {
+        vPos = vi.local_pos - local_rect.p0;
+    }
 
     vec2 start_point = gradient.start_end_point.xy;
     vec2 end_point = gradient.start_end_point.zw;

gfx/webrender/res/brush_radial_gradient.glsl

@@ -49,11 +49,16 @@ void brush_vs(
     mat4 transform,
     PictureTask pic_task,
     int brush_flags,
-    vec4 unused
+    vec4 texel_rect
 ) {
     RadialGradient gradient = fetch_radial_gradient(prim_address);
 
-    vPos = vi.local_pos - local_rect.p0;
+    if ((brush_flags & BRUSH_FLAG_SEGMENT_RELATIVE) != 0) {
+        vPos = (vi.local_pos - segment_rect.p0) / segment_rect.size;
+        vPos = vPos * (texel_rect.zw - texel_rect.xy) + texel_rect.xy;
+    } else {
+        vPos = vi.local_pos - local_rect.p0;
+    }
 
     vCenter = gradient.center_start_end_radius.xy;
     vStartRadius = gradient.center_start_end_radius.z;

gfx/webrender/res/clip_scroll.glsl

@@ -1,88 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#ifdef WR_VERTEX_SHADER
-#define VECS_PER_CLIP_SCROLL_NODE   9
-
-uniform HIGHP_SAMPLER_FLOAT sampler2D sClipScrollNodes;
-
-struct ClipScrollNode {
-    mat4 transform;
-    mat4 inv_transform;
-    bool is_axis_aligned;
-};
-
-ClipScrollNode fetch_clip_scroll_node(int index) {
-    ClipScrollNode node;
-
-    // Create a UV base coord for each 8 texels.
-    // This is required because trying to use an offset
-    // of more than 8 texels doesn't work on some versions
-    // of OSX.
-    ivec2 uv = get_fetch_uv(index, VECS_PER_CLIP_SCROLL_NODE);
-    ivec2 uv0 = ivec2(uv.x + 0, uv.y);
-    ivec2 uv1 = ivec2(uv.x + 8, uv.y);
-
-    node.transform[0] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(0, 0));
-    node.transform[1] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(1, 0));
-    node.transform[2] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(2, 0));
-    node.transform[3] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(3, 0));
-
-    node.inv_transform[0] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(4, 0));
-    node.inv_transform[1] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(5, 0));
-    node.inv_transform[2] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(6, 0));
-    node.inv_transform[3] = TEXEL_FETCH(sClipScrollNodes, uv0, 0, ivec2(7, 0));
-
-    vec4 misc = TEXEL_FETCH(sClipScrollNodes, uv1, 0, ivec2(0, 0));
-    node.is_axis_aligned = misc.x == 0.0;
-
-    return node;
-}
-
-// Return the intersection of the plane (set up by "normal" and "point")
-// with the ray (set up by "ray_origin" and "ray_dir"),
-// writing the resulting scaler into "t".
-bool ray_plane(vec3 normal, vec3 pt, vec3 ray_origin, vec3 ray_dir, out float t)
-{
-    float denom = dot(normal, ray_dir);
-    if (abs(denom) > 1e-6) {
-        vec3 d = pt - ray_origin;
-        t = dot(d, normal) / denom;
-        return t >= 0.0;
-    }
-
-    return false;
-}
-
-// Apply the inverse transform "inv_transform"
-// to the reference point "ref" in CSS space,
-// producing a local point on a ClipScrollNode plane,
-// set by a base point "a" and a normal "n".
-vec4 untransform(vec2 ref, vec3 n, vec3 a, mat4 inv_transform) {
-    vec3 p = vec3(ref, -10000.0);
-    vec3 d = vec3(0, 0, 1.0);
-
-    float t = 0.0;
-    // get an intersection of the ClipScrollNode plane with Z axis vector,
-    // originated from the "ref" point
-    ray_plane(n, a, p, d, t);
-    float z = p.z + d.z * t; // Z of the visible point on the ClipScrollNode
-
-    vec4 r = inv_transform * vec4(ref, z, 1.0);
-    return r;
-}
-
-// Given a CSS space position, transform it back into the ClipScrollNode space.
-vec4 get_node_pos(vec2 pos, ClipScrollNode node) {
-    // get a point on the scroll node plane
-    vec4 ah = node.transform * vec4(0.0, 0.0, 0.0, 1.0);
-    vec3 a = ah.xyz / ah.w;
-
-    // get the normal to the scroll node plane
-    vec3 n = transpose(mat3(node.inv_transform)) * vec3(0.0, 0.0, 1.0);
-    return untransform(pos, n, a, node.inv_transform);
-}
-
-#endif //WR_VERTEX_SHADER
-

gfx/webrender/res/clip_shared.glsl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#include rect,clip_scroll,render_task,resource_cache,snap,transform
+#include rect,render_task,resource_cache,snap,transform
 
 #ifdef WR_VERTEX_SHADER
 
@@ -19,7 +19,7 @@ in ivec4 aClipDataResourceAddress;
 
 struct ClipMaskInstance {
     int render_task_address;
-    int scroll_node_id;
+    int transform_id;
     int segment;
     ivec2 clip_data_address;
     ivec2 resource_address;
@@ -29,7 +29,7 @@ ClipMaskInstance fetch_clip_item() {
     ClipMaskInstance cmi;
 
     cmi.render_task_address = aClipRenderTaskAddress;
-    cmi.scroll_node_id = aScrollNodeId;
+    cmi.transform_id = aScrollNodeId;
     cmi.segment = aClipSegment;
     cmi.clip_data_address = aClipDataResourceAddress.xy;
     cmi.resource_address = aClipDataResourceAddress.zw;
@@ -51,20 +51,20 @@ RectWithSize intersect_rect(RectWithSize a, RectWithSize b) {
 // The transformed vertex function that always covers the whole clip area,
 // which is the intersection of all clip instances of a given primitive
 ClipVertexInfo write_clip_tile_vertex(RectWithSize local_clip_rect,
-                                      ClipScrollNode scroll_node,
+                                      Transform transform,
                                       ClipArea area) {
     vec2 device_pos = area.screen_origin + aPosition.xy * area.common_data.task_rect.size;
     vec2 actual_pos = device_pos;
 
-    if (scroll_node.is_axis_aligned) {
+    if (transform.is_axis_aligned) {
         vec4 snap_positions = compute_snap_positions(
-            scroll_node.transform,
+            transform.m,
             local_clip_rect
         );
 
         vec2 snap_offsets = compute_snap_offset_impl(
             device_pos,
-            scroll_node.transform,
+            transform.m,
             local_clip_rect,
             RectWithSize(snap_positions.xy, snap_positions.zw - snap_positions.xy),
             snap_positions,
@@ -81,7 +81,7 @@ ClipVertexInfo write_clip_tile_vertex(RectWithSize local_clip_rect,
     if (area.local_space) {
         node_pos = vec4(actual_pos / uDevicePixelRatio, 0.0, 1.0);
     } else {
-        node_pos = get_node_pos(actual_pos / uDevicePixelRatio, scroll_node);
+        node_pos = get_node_pos(actual_pos / uDevicePixelRatio, transform);
     }
 
     // compute the point position inside the scroll node, in CSS space

gfx/webrender/res/cs_clip_box_shadow.glsl

@@ -41,12 +41,12 @@ BoxShadowData fetch_data(ivec2 address) {
 void main(void) {
     ClipMaskInstance cmi = fetch_clip_item();
     ClipArea area = fetch_clip_area(cmi.render_task_address);
-    ClipScrollNode scroll_node = fetch_clip_scroll_node(cmi.scroll_node_id);
+    Transform transform = fetch_transform(cmi.transform_id);
     BoxShadowData bs_data = fetch_data(cmi.clip_data_address);
     ImageResource res = fetch_image_resource_direct(cmi.resource_address);
 
     ClipVertexInfo vi = write_clip_tile_vertex(bs_data.dest_rect,
-                                               scroll_node,
+                                               transform,
                                                area);
 
     vLayer = res.layer;

gfx/webrender/res/cs_clip_image.glsl

@@ -26,13 +26,13 @@ ImageMaskData fetch_mask_data(ivec2 address) {
 void main(void) {
     ClipMaskInstance cmi = fetch_clip_item();
     ClipArea area = fetch_clip_area(cmi.render_task_address);
-    ClipScrollNode scroll_node = fetch_clip_scroll_node(cmi.scroll_node_id);
+    Transform transform = fetch_transform(cmi.transform_id);
     ImageMaskData mask = fetch_mask_data(cmi.clip_data_address);
     RectWithSize local_rect = mask.local_rect;
     ImageResource res = fetch_image_resource_direct(cmi.resource_address);
 
     ClipVertexInfo vi = write_clip_tile_vertex(local_rect,
-                                               scroll_node,
+                                               transform,
                                                area);
 
     vPos = vi.local_pos;

gfx/webrender/res/cs_clip_line.glsl

@@ -43,11 +43,11 @@ LineDecorationData fetch_data(ivec2 address) {
 void main(void) {
     ClipMaskInstance cmi = fetch_clip_item();
     ClipArea area = fetch_clip_area(cmi.render_task_address);
-    ClipScrollNode scroll_node = fetch_clip_scroll_node(cmi.scroll_node_id);
+    Transform transform = fetch_transform(cmi.transform_id);
     LineDecorationData data = fetch_data(cmi.clip_data_address);
 
     ClipVertexInfo vi = write_clip_tile_vertex(data.local_rect,
-                                               scroll_node,
+                                               transform,
                                                area);
 
 

gfx/webrender/res/cs_clip_rectangle.glsl

@@ -60,11 +60,11 @@ ClipData fetch_clip(ivec2 address) {
 void main(void) {
     ClipMaskInstance cmi = fetch_clip_item();
     ClipArea area = fetch_clip_area(cmi.render_task_address);
-    ClipScrollNode scroll_node = fetch_clip_scroll_node(cmi.scroll_node_id);
+    Transform transform = fetch_transform(cmi.transform_id);
     ClipData clip = fetch_clip(cmi.clip_data_address);
     RectWithSize local_rect = clip.rect.rect;
 
-    ClipVertexInfo vi = write_clip_tile_vertex(local_rect, scroll_node, area);
+    ClipVertexInfo vi = write_clip_tile_vertex(local_rect, transform, area);
     vPos = vi.local_pos;
 
     vClipMode = clip.rect.mode.x;

gfx/webrender/res/prim_shared.glsl

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#include rect,clip_scroll,render_task,resource_cache,snap,transform
+#include rect,render_task,resource_cache,snap,transform
 
 #define EXTEND_MODE_CLAMP  0
 #define EXTEND_MODE_REPEAT 1
@@ -32,11 +32,6 @@ varying vec3 vClipMaskUv;
 
 #ifdef WR_VERTEX_SHADER
 
-#define VECS_PER_LOCAL_CLIP_RECT    1
-#define VECS_PER_PRIM_HEADER        2
-#define VECS_PER_TEXT_RUN           3
-#define VECS_PER_GRADIENT_STOP      2
-
 #define COLOR_MODE_FROM_PASS          0
 #define COLOR_MODE_ALPHA              1
 #define COLOR_MODE_SUBPX_CONST_COLOR  2
@@ -47,16 +42,46 @@ varying vec3 vClipMaskUv;
 #define COLOR_MODE_BITMAP             7
 #define COLOR_MODE_COLOR_BITMAP       8
 
-uniform HIGHP_SAMPLER_FLOAT sampler2D sLocalClipRects;
+uniform HIGHP_SAMPLER_FLOAT sampler2D sPrimitiveHeadersF;
+uniform HIGHP_SAMPLER_FLOAT isampler2D sPrimitiveHeadersI;
 
 // Instanced attributes
-in ivec4 aData0;
-in ivec4 aData1;
+in ivec4 aData;
 
-RectWithSize fetch_clip_chain_rect(int index) {
-    ivec2 uv = get_fetch_uv(index, VECS_PER_LOCAL_CLIP_RECT);
-    vec4 rect = TEXEL_FETCH(sLocalClipRects, uv, 0, ivec2(0, 0));
-    return RectWithSize(rect.xy, rect.zw);
+#define VECS_PER_PRIM_HEADER_F 2
+#define VECS_PER_PRIM_HEADER_I 2
+
+struct PrimitiveHeader {
+    RectWithSize local_rect;
+    RectWithSize local_clip_rect;
+    float z;
+    int specific_prim_address;
+    int render_task_index;
+    int clip_task_index;
+    int transform_id;
+    ivec3 user_data;
+};
+
+PrimitiveHeader fetch_prim_header(int index) {
+    PrimitiveHeader ph;
+
+    ivec2 uv_f = get_fetch_uv(index, VECS_PER_PRIM_HEADER_F);
+    vec4 local_rect = TEXEL_FETCH(sPrimitiveHeadersF, uv_f, 0, ivec2(0, 0));
+    vec4 local_clip_rect = TEXEL_FETCH(sPrimitiveHeadersF, uv_f, 0, ivec2(1, 0));
+    ph.local_rect = RectWithSize(local_rect.xy, local_rect.zw);
+    ph.local_clip_rect = RectWithSize(local_clip_rect.xy, local_clip_rect.zw);
+
+    ivec2 uv_i = get_fetch_uv(index, VECS_PER_PRIM_HEADER_I);
+    ivec4 data0 = TEXEL_FETCH(sPrimitiveHeadersI, uv_i, 0, ivec2(0, 0));
+    ivec4 data1 = TEXEL_FETCH(sPrimitiveHeadersI, uv_i, 0, ivec2(1, 0));
+    ph.z = float(data0.x);
+    ph.render_task_index = data0.y;
+    ph.specific_prim_address = data0.z;
+    ph.clip_task_index = data0.w;
+    ph.transform_id = data1.x;
+    ph.user_data = data1.yzw;
+
+    return ph;
 }
 
 struct VertexInfo {
@@ -69,7 +94,7 @@ struct VertexInfo {
 VertexInfo write_vertex(RectWithSize instance_rect,
                         RectWithSize local_clip_rect,
                         float z,
-                        ClipScrollNode scroll_node,
+                        Transform transform,
                         PictureTask task,
                         RectWithSize snap_rect) {
 
@@ -82,13 +107,13 @@ VertexInfo write_vertex(RectWithSize instance_rect,
     /// Compute the snapping offset.
     vec2 snap_offset = compute_snap_offset(
         clamped_local_pos,
-        scroll_node.transform,
+        transform.m,
         snap_rect,
         vec2(0.5)
     );
 
     // Transform the current vertex to world space.
-    vec4 world_pos = scroll_node.transform * vec4(clamped_local_pos, 0.0, 1.0);
+    vec4 world_pos = transform.m * vec4(clamped_local_pos, 0.0, 1.0);
 
     // Convert the world positions to device pixel space.
     vec2 device_pos = world_pos.xy / world_pos.w * uDevicePixelRatio;
@@ -135,7 +160,7 @@ VertexInfo write_transform_vertex(RectWithSize local_segment_rect,
                                   RectWithSize local_clip_rect,
                                   vec4 clip_edge_mask,
                                   float z,
-                                  ClipScrollNode scroll_node,
+                                  Transform transform,
                                   PictureTask task,
                                   bool do_perspective_interpolation) {
     // Calculate a clip rect from local_rect + local clip
@@ -168,7 +193,7 @@ VertexInfo write_transform_vertex(RectWithSize local_segment_rect,
     vec2 local_pos = local_segment_rect.p0 + local_segment_rect.size * aPosition.xy;
 
     // Transform the current vertex to the world cpace.
-    vec4 world_pos = scroll_node.transform * vec4(local_pos, 0.0, 1.0);
+    vec4 world_pos = transform.m * vec4(local_pos, 0.0, 1.0);
 
     // Convert the world positions to device pixel space.
     vec2 device_pos = world_pos.xy / world_pos.w * uDevicePixelRatio;

gfx/webrender/res/ps_split_composite.glsl

@@ -44,10 +44,10 @@ struct SplitCompositeInstance {
 SplitCompositeInstance fetch_composite_instance() {
     SplitCompositeInstance ci;
 
-    ci.render_task_index = aData0.x;
-    ci.src_task_index = aData0.y;
-    ci.polygons_address = aData0.z;
-    ci.z = float(aData0.w);
+    ci.render_task_index = aData.x;
+    ci.src_task_index = aData.y;
+    ci.polygons_address = aData.z;
+    ci.z = float(aData.w);
 
     return ci;
 }

gfx/webrender/res/ps_text_run.glsl

@@ -15,6 +15,8 @@ varying vec4 vUvClip;
 
 #ifdef WR_VERTEX_SHADER
 
+#define VECS_PER_TEXT_RUN           3
+
 struct Glyph {
     vec2 offset;
 };
@@ -57,94 +59,16 @@ TextRun fetch_text_run(int address) {
     return TextRun(data[0], data[1], data[2].xy);
 }
 
-struct PrimitiveInstance {
-    int prim_address;
-    int specific_prim_address;
-    int render_task_index;
-    int clip_task_index;
-    int scroll_node_id;
-    int clip_chain_rect_index;
-    int z;
-    int user_data0;
-    int user_data1;
-    int user_data2;
-};
-
-PrimitiveInstance fetch_prim_instance() {
-    PrimitiveInstance pi;
-
-    pi.prim_address = aData0.x;
-    pi.specific_prim_address = pi.prim_address + VECS_PER_PRIM_HEADER;
-    pi.render_task_index = aData0.y % 0x10000;
-    pi.clip_task_index = aData0.y / 0x10000;
-    pi.clip_chain_rect_index = aData0.z;
-    pi.scroll_node_id = aData0.w;
-    pi.z = aData1.x;
-    pi.user_data0 = aData1.y;
-    pi.user_data1 = aData1.z;
-    pi.user_data2 = aData1.w;
-
-    return pi;
-}
-
-struct Primitive {
-    ClipScrollNode scroll_node;
-    ClipArea clip_area;
-    PictureTask task;
-    RectWithSize local_rect;
-    RectWithSize local_clip_rect;
-    int specific_prim_address;
-    int user_data0;
-    int user_data1;
-    int user_data2;
-    float z;
-};
-
-struct PrimitiveGeometry {
-    RectWithSize local_rect;
-    RectWithSize local_clip_rect;
-};
-
-PrimitiveGeometry fetch_primitive_geometry(int address) {
-    vec4 geom[2] = fetch_from_resource_cache_2(address);
-    return PrimitiveGeometry(RectWithSize(geom[0].xy, geom[0].zw),
-                             RectWithSize(geom[1].xy, geom[1].zw));
-}
-
-Primitive load_primitive() {
-    PrimitiveInstance pi = fetch_prim_instance();
-
-    Primitive prim;
-
-    prim.scroll_node = fetch_clip_scroll_node(pi.scroll_node_id);
-    prim.clip_area = fetch_clip_area(pi.clip_task_index);
-    prim.task = fetch_picture_task(pi.render_task_index);
-
-    RectWithSize clip_chain_rect = fetch_clip_chain_rect(pi.clip_chain_rect_index);
-
-    PrimitiveGeometry geom = fetch_primitive_geometry(pi.prim_address);
-    prim.local_rect = geom.local_rect;
-    prim.local_clip_rect = intersect_rects(clip_chain_rect, geom.local_clip_rect);
-
-    prim.specific_prim_address = pi.specific_prim_address;
-    prim.user_data0 = pi.user_data0;
-    prim.user_data1 = pi.user_data1;
-    prim.user_data2 = pi.user_data2;
-    prim.z = float(pi.z);
-
-    return prim;
-}
-
 VertexInfo write_text_vertex(vec2 clamped_local_pos,
                              RectWithSize local_clip_rect,
                              float z,
-                             ClipScrollNode scroll_node,
+                             Transform transform,
                              PictureTask task,
                              vec2 text_offset,
                              RectWithSize snap_rect,
                              vec2 snap_bias) {
     // Transform the current vertex to world space.
-    vec4 world_pos = scroll_node.transform * vec4(clamped_local_pos, 0.0, 1.0);
+    vec4 world_pos = transform.m * vec4(clamped_local_pos, 0.0, 1.0);
 
     // Convert the world positions to device pixel space.
     float device_scale = uDevicePixelRatio / world_pos.w;
@@ -159,13 +83,13 @@ VertexInfo write_text_vertex(vec2 clamped_local_pos,
     bool remove_subpx_offset = true;
 #else
     // Compute the snapping offset only if the scroll node transform is axis-aligned.
-    bool remove_subpx_offset = scroll_node.is_axis_aligned;
+    bool remove_subpx_offset = transform.is_axis_aligned;
 #endif
     if (remove_subpx_offset) {
         // Ensure the transformed text offset does not contain a subpixel translation
         // such that glyph snapping is stable for equivalent glyph subpixel positions.
-        vec2 world_text_offset = mat2(scroll_node.transform) * text_offset;
-        vec2 device_text_pos = (scroll_node.transform[3].xy + world_text_offset) * device_scale;
+        vec2 world_text_offset = mat2(transform.m) * text_offset;
+        vec2 device_text_pos = (transform.m[3].xy + world_text_offset) * device_scale;
         final_pos += floor(device_text_pos + 0.5) - device_text_pos;
 
 #ifdef WR_FEATURE_GLYPH_TRANSFORM
@@ -177,7 +101,7 @@ VertexInfo write_text_vertex(vec2 clamped_local_pos,
 #else
         // The transformed text offset has already been snapped, so remove it from the transform
         // when snapping the glyph.
-        mat4 snap_transform = scroll_node.transform;
+        mat4 snap_transform = transform.m;
         snap_transform[3].xy = -world_text_offset;
         final_pos += compute_snap_offset(
             clamped_local_pos,
@@ -201,31 +125,37 @@ VertexInfo write_text_vertex(vec2 clamped_local_pos,
 }
 
 void main(void) {
-    Primitive prim = load_primitive();
-    TextRun text = fetch_text_run(prim.specific_prim_address);
+    int prim_header_address = aData.x;
+    int glyph_index = aData.y;
+    int resource_address = aData.z;
+    int subpx_dir = aData.w >> 16;
+    int color_mode = aData.w & 0xffff;
 
-    int glyph_index = prim.user_data0;
-    int resource_address = prim.user_data1;
-    int subpx_dir = prim.user_data2 >> 16;
-    int color_mode = prim.user_data2 & 0xffff;
+    PrimitiveHeader ph = fetch_prim_header(prim_header_address);
+
+    Transform transform = fetch_transform(ph.transform_id);
+    ClipArea clip_area = fetch_clip_area(ph.clip_task_index);
+    PictureTask task = fetch_picture_task(ph.render_task_index);
+
+    TextRun text = fetch_text_run(ph.specific_prim_address);
 
     if (color_mode == COLOR_MODE_FROM_PASS) {
         color_mode = uMode;
     }
 
-    Glyph glyph = fetch_glyph(prim.specific_prim_address, glyph_index);
+    Glyph glyph = fetch_glyph(ph.specific_prim_address, glyph_index);
     GlyphResource res = fetch_glyph_resource(resource_address);
 
 #ifdef WR_FEATURE_GLYPH_TRANSFORM
     // Transform from local space to glyph space.
-    mat2 transform = mat2(prim.scroll_node.transform) * uDevicePixelRatio;
+    mat2 glyph_transform = mat2(transform.m) * uDevicePixelRatio;
 
     // Compute the glyph rect in glyph space.
-    RectWithSize glyph_rect = RectWithSize(res.offset + transform * (text.offset + glyph.offset),
+    RectWithSize glyph_rect = RectWithSize(res.offset + glyph_transform * (text.offset + glyph.offset),
                                            res.uv_rect.zw - res.uv_rect.xy);
 
     // Transform the glyph rect back to local space.
-    mat2 inv = inverse(transform);
+    mat2 inv = inverse(glyph_transform);
     RectWithSize local_rect = transform_rect(glyph_rect, inv);
 
     // Select the corner of the glyph's local space rect that we are processing.
@@ -234,9 +164,9 @@ void main(void) {
     // If the glyph's local rect would fit inside the local clip rect, then select a corner from
     // the device space glyph rect to reduce overdraw of clipped pixels in the fragment shader.
     // Otherwise, fall back to clamping the glyph's local rect to the local clip rect.
-    local_pos = rect_inside_rect(local_rect, prim.local_clip_rect) ?
+    local_pos = rect_inside_rect(local_rect, ph.local_clip_rect) ?
                     inv * (glyph_rect.p0 + glyph_rect.size * aPosition.xy) :
-                    clamp_rect(local_pos, prim.local_clip_rect);
+                    clamp_rect(local_pos, ph.local_clip_rect);
 #else
     // Scale from glyph space to local space.
     float scale = res.scale / uDevicePixelRatio;
@@ -249,7 +179,7 @@ void main(void) {
     vec2 local_pos = glyph_rect.p0 + glyph_rect.size * aPosition.xy;
 
     // Clamp to the local clip rect.
-    local_pos = clamp_rect(local_pos, prim.local_clip_rect);
+    local_pos = clamp_rect(local_pos, ph.local_clip_rect);
 #endif
 
     vec2 snap_bias;
@@ -278,22 +208,22 @@ void main(void) {
     }
 
     VertexInfo vi = write_text_vertex(local_pos,
-                                      prim.local_clip_rect,
-                                      prim.z,
-                                      prim.scroll_node,
-                                      prim.task,
+                                      ph.local_clip_rect,
+                                      ph.z,
+                                      transform,
+                                      task,
                                       text.offset,
                                       glyph_rect,
                                       snap_bias);
 
 #ifdef WR_FEATURE_GLYPH_TRANSFORM
-    vec2 f = (transform * vi.local_pos - glyph_rect.p0) / glyph_rect.size;
+    vec2 f = (glyph_transform * vi.local_pos - glyph_rect.p0) / glyph_rect.size;
     vUvClip = vec4(f, 1.0 - f);
 #else
     vec2 f = (vi.local_pos - glyph_rect.p0) / glyph_rect.size;
 #endif
 
-    write_clip(vi.screen_pos, prim.clip_area);
+    write_clip(vi.screen_pos, clip_area);
 
     switch (color_mode) {
         case COLOR_MODE_ALPHA:

gfx/webrender/res/snap.glsl

@@ -8,7 +8,7 @@ vec4 compute_snap_positions(mat4 transform, RectWithSize snap_rect) {
     // Ensure that the snap rect is at *least* one device pixel in size.
     // TODO(gw): It's not clear to me that this is "correct". Specifically,
     //           how should it interact with sub-pixel snap rects when there
-    //           is a scroll_node transform with scale present? But it does fix
+    //           is a transform with scale present? But it does fix
     //           the test cases we have in Servo that are failing without it
     //           and seem better than not having this at all.
     snap_rect.size = max(snap_rect.size, vec2(1.0 / uDevicePixelRatio));
@@ -41,7 +41,7 @@ vec2 compute_snap_offset_impl(
 }
 
 // Compute a snapping offset in world space (adjusted to pixel ratio),
-// given local position on the scroll_node and a snap rectangle.
+// given local position on the transform and a snap rectangle.
 vec2 compute_snap_offset(vec2 local_pos,
                          mat4 transform,
                          RectWithSize snap_rect,

gfx/webrender/res/transform.glsl

@@ -6,10 +6,89 @@ flat varying vec4 vTransformBounds;
 
 #ifdef WR_VERTEX_SHADER
 
+#define VECS_PER_TRANSFORM   8
+uniform HIGHP_SAMPLER_FLOAT sampler2D sTransformPalette;
+
 void init_transform_vs(vec4 local_bounds) {
     vTransformBounds = local_bounds;
 }
 
+struct Transform {
+    mat4 m;
+    mat4 inv_m;
+    bool is_axis_aligned;
+};
+
+Transform fetch_transform(int id) {
+    Transform transform;
+
+    transform.is_axis_aligned = (id >> 24) == 0;
+    int index = id & 0x00ffffff;
+
+    // Create a UV base coord for each 8 texels.
+    // This is required because trying to use an offset
+    // of more than 8 texels doesn't work on some versions
+    // of OSX.
+    ivec2 uv = get_fetch_uv(index, VECS_PER_TRANSFORM);
+    ivec2 uv0 = ivec2(uv.x + 0, uv.y);
+
+    transform.m[0] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(0, 0));
+    transform.m[1] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(1, 0));
+    transform.m[2] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(2, 0));
+    transform.m[3] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(3, 0));
+
+    transform.inv_m[0] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(4, 0));
+    transform.inv_m[1] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(5, 0));
+    transform.inv_m[2] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(6, 0));
+    transform.inv_m[3] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(7, 0));
+
+    return transform;
+}
+
+// Return the intersection of the plane (set up by "normal" and "point")
+// with the ray (set up by "ray_origin" and "ray_dir"),
+// writing the resulting scaler into "t".
+bool ray_plane(vec3 normal, vec3 pt, vec3 ray_origin, vec3 ray_dir, out float t)
+{
+    float denom = dot(normal, ray_dir);
+    if (abs(denom) > 1e-6) {
+        vec3 d = pt - ray_origin;
+        t = dot(d, normal) / denom;
+        return t >= 0.0;
+    }
+
+    return false;
+}
+
+// Apply the inverse transform "inv_transform"
+// to the reference point "ref" in CSS space,
+// producing a local point on a Transform plane,
+// set by a base point "a" and a normal "n".
+vec4 untransform(vec2 ref, vec3 n, vec3 a, mat4 inv_transform) {
+    vec3 p = vec3(ref, -10000.0);
+    vec3 d = vec3(0, 0, 1.0);
+
+    float t = 0.0;
+    // get an intersection of the Transform plane with Z axis vector,
+    // originated from the "ref" point
+    ray_plane(n, a, p, d, t);
+    float z = p.z + d.z * t; // Z of the visible point on the Transform
+
+    vec4 r = inv_transform * vec4(ref, z, 1.0);
+    return r;
+}
+
+// Given a CSS space position, transform it back into the Transform space.
+vec4 get_node_pos(vec2 pos, Transform transform) {
+    // get a point on the scroll node plane
+    vec4 ah = transform.m * vec4(0.0, 0.0, 0.0, 1.0);
+    vec3 a = ah.xyz / ah.w;
+
+    // get the normal to the scroll node plane
+    vec3 n = transpose(mat3(transform.inv_m)) * vec3(0.0, 0.0, 1.0);
+    return untransform(pos, n, a, transform.inv_m);
+}
+
 #endif //WR_VERTEX_SHADER
 
 #ifdef WR_FRAGMENT_SHADER

gfx/webrender/src/batch.rs

@@ -11,10 +11,10 @@ use clip_scroll_tree::{CoordinateSystemId};
 use euclid::{TypedTransform3D, vec3};
 use glyph_rasterizer::GlyphFormat;
 use gpu_cache::{GpuCache, GpuCacheHandle, GpuCacheAddress};
-use gpu_types::{BrushFlags, BrushInstance, ClipChainRectIndex};
-use gpu_types::{ClipMaskInstance, ClipScrollNodeIndex, SplitCompositeInstance};
-use gpu_types::{PrimitiveInstance, RasterizationSpace, GlyphInstance, ZBufferId};
-use gpu_types::ZBufferIdGenerator;
+use gpu_types::{BrushFlags, BrushInstance, PrimitiveHeaders};
+use gpu_types::{ClipMaskInstance, SplitCompositeInstance};
+use gpu_types::{PrimitiveInstance, RasterizationSpace, GlyphInstance};
+use gpu_types::{PrimitiveHeader, PrimitiveHeaderIndex, TransformPaletteId, TransformPalette};
 use internal_types::{FastHashMap, SavedTargetIndex, SourceTexture};
 use picture::{PictureCompositeMode, PicturePrimitive, PictureSurface};
 use plane_split::{BspSplitter, Polygon, Splitter};
@@ -29,7 +29,7 @@ use resource_cache::{CacheItem, GlyphFetchResult, ImageRequest, ResourceCache};
 use scene::FilterOpHelpers;
 use std::{usize, f32, i32};
 use tiling::{RenderTargetContext};
-use util::{MatrixHelpers, TransformedRectKind};
+use util::{TransformedRectKind};
 
 // Special sentinel value recognized by the shader. It is considered to be
 // a dummy task that doesn't mask out anything.
@@ -455,7 +455,7 @@ impl AlphaBatchBuilder {
         gpu_cache: &mut GpuCache,
         render_tasks: &RenderTaskTree,
         deferred_resolves: &mut Vec<DeferredResolve>,
-        z_generator: &mut ZBufferIdGenerator,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
         let task_address = render_tasks.get_task_address(task_id);
 
@@ -476,10 +476,10 @@ impl AlphaBatchBuilder {
         // Add each run in this picture to the batch.
         for run in &pic.runs {
             let scroll_node = &ctx.clip_scroll_tree.nodes[run.clip_and_scroll.scroll_node_id.0];
-            let scroll_id = scroll_node.node_data_index;
+            let transform_id = ctx.transforms.get_id(scroll_node.transform_index);
             self.add_run_to_batch(
                 run,
-                scroll_id,
+                transform_id,
                 ctx,
                 gpu_cache,
                 render_tasks,
@@ -488,7 +488,7 @@ impl AlphaBatchBuilder {
                 deferred_resolves,
                 &mut splitter,
                 content_origin,
-                z_generator,
+                prim_headers,
             );
         }
 
@@ -526,7 +526,7 @@ impl AlphaBatchBuilder {
                 task_address,
                 source_task_address,
                 gpu_address,
-                z_generator.next(),
+                prim_headers.z_generator.next(),
             );
 
             batch.push(PrimitiveInstance::from(instance));
@@ -539,7 +539,7 @@ impl AlphaBatchBuilder {
     fn add_run_to_batch(
         &mut self,
         run: &PrimitiveRun,
-        scroll_id: ClipScrollNodeIndex,
+        transform_id: TransformPaletteId,
         ctx: &RenderTargetContext,
         gpu_cache: &mut GpuCache,
         render_tasks: &RenderTaskTree,
@@ -548,7 +548,7 @@ impl AlphaBatchBuilder {
         deferred_resolves: &mut Vec<DeferredResolve>,
         splitter: &mut BspSplitter<f64, WorldPixel>,
         content_origin: DeviceIntPoint,
-        z_generator: &mut ZBufferIdGenerator,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
         for i in 0 .. run.count {
             let prim_index = PrimitiveIndex(run.base_prim_index.0 + i);
@@ -556,8 +556,7 @@ impl AlphaBatchBuilder {
 
             if metadata.screen_rect.is_some() {
                 self.add_prim_to_batch(
-                    metadata.clip_chain_rect_index,
-                    scroll_id,
+                    transform_id,
                     prim_index,
                     ctx,
                     gpu_cache,
@@ -567,7 +566,7 @@ impl AlphaBatchBuilder {
                     deferred_resolves,
                     splitter,
                     content_origin,
-                    z_generator,
+                    prim_headers,
                 );
             }
         }
@@ -579,8 +578,7 @@ impl AlphaBatchBuilder {
     // in that picture are being drawn into the same target.
     fn add_prim_to_batch(
         &mut self,
-        clip_chain_rect_index: ClipChainRectIndex,
-        scroll_id: ClipScrollNodeIndex,
+        transform_id: TransformPaletteId,
         prim_index: PrimitiveIndex,
         ctx: &RenderTargetContext,
         gpu_cache: &mut GpuCache,
@@ -590,18 +588,16 @@ impl AlphaBatchBuilder {
         deferred_resolves: &mut Vec<DeferredResolve>,
         splitter: &mut BspSplitter<f64, WorldPixel>,
         content_origin: DeviceIntPoint,
-        z_generator: &mut ZBufferIdGenerator,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
-        let z = z_generator.next();
         let prim_metadata = ctx.prim_store.get_metadata(prim_index);
         #[cfg(debug_assertions)] //TODO: why is this needed?
         debug_assert_eq!(prim_metadata.prepared_frame_id, render_tasks.frame_id());
 
-        let scroll_node = &ctx.node_data[scroll_id.0 as usize];
         // TODO(gw): Calculating this for every primitive is a bit
         //           wasteful. We should probably cache this in
         //           the scroll node...
-        let transform_kind = scroll_node.transform.transform_kind();
+        let transform_kind = transform_id.transform_kind();
 
         let screen_rect = prim_metadata.screen_rect.expect("bug");
         let task_relative_bounding_rect = DeviceIntRect::new(
@@ -648,6 +644,15 @@ impl AlphaBatchBuilder {
             BlendMode::None
         };
 
+        let prim_header = PrimitiveHeader {
+            local_rect: prim_metadata.local_rect,
+            local_clip_rect: prim_metadata.combined_local_clip_rect,
+            task_address,
+            specific_prim_address: prim_cache_address,
+            clip_task_address,
+            transform_id,
+        };
+
         match prim_metadata.prim_kind {
             PrimitiveKind::Brush => {
                 let brush = &ctx.prim_store.cpu_brushes[prim_metadata.cpu_prim_index.0];
@@ -701,23 +706,19 @@ impl AlphaBatchBuilder {
                                                     textures,
                                                 );
                                                 let batch = self.batch_list.get_suitable_batch(key, &task_relative_bounding_rect);
+                                                let prim_header_index = prim_headers.push(&prim_header, [
+                                                    uv_rect_address.as_int(),
+                                                    (ShaderColorMode::ColorBitmap as i32) << 16 |
+                                                    RasterizationSpace::Screen as i32,
+                                                    0,
+                                                ]);
 
                                                 let instance = BrushInstance {
-                                                    picture_address: task_address,
-                                                    prim_address: prim_cache_address,
-                                                    clip_chain_rect_index,
-                                                    scroll_id,
-                                                    clip_task_address,
-                                                    z,
+                                                    prim_header_index,
                                                     segment_index: 0,
                                                     edge_flags: EdgeAaSegmentMask::empty(),
                                                     brush_flags: BrushFlags::empty(),
-                                                    user_data: [
-                                                        uv_rect_address.as_int(),
-                                                        (ShaderColorMode::ColorBitmap as i32) << 16 |
-                                                        RasterizationSpace::Screen as i32,
-                                                        0,
-                                                    ],
+                                                    clip_task_address,
                                                 };
                                                 batch.push(PrimitiveInstance::from(instance));
                                                 false
@@ -727,7 +728,7 @@ impl AlphaBatchBuilder {
                                             }
                                         }
                                     }
-                                    FilterOp::DropShadow(..) => {
+                                    FilterOp::DropShadow(offset, ..) => {
                                         // Draw an instance of the shadow first, following by the content.
 
                                         // Both the shadow and the content get drawn as a brush image.
@@ -768,33 +769,44 @@ impl AlphaBatchBuilder {
                                             // Get the GPU cache address of the extra data handle.
                                             let shadow_prim_address = gpu_cache.get_address(&picture.extra_gpu_data_handle);
 
+                                            let content_prim_header_index = prim_headers.push(&prim_header, [
+                                                content_uv_rect_address,
+                                                (ShaderColorMode::ColorBitmap as i32) << 16 |
+                                                RasterizationSpace::Screen as i32,
+                                                0,
+                                            ]);
+
+                                            let shadow_rect = prim_metadata.local_rect.translate(&offset);
+                                            let shadow_clip_rect = prim_metadata.local_clip_rect.translate(&offset);
+
+                                            let shadow_prim_header = PrimitiveHeader {
+                                                local_rect: shadow_rect,
+                                                local_clip_rect: shadow_clip_rect,
+                                                specific_prim_address: shadow_prim_address,
+                                                ..prim_header
+                                            };
+
+                                            let shadow_prim_header_index = prim_headers.push(&shadow_prim_header, [
+                                                shadow_uv_rect_address,
+                                                (ShaderColorMode::Alpha as i32) << 16 |
+                                                RasterizationSpace::Screen as i32,
+                                                0,
+                                            ]);
+
                                             let shadow_instance = BrushInstance {
-                                                picture_address: task_address,
-                                                prim_address: shadow_prim_address,
-                                                clip_chain_rect_index,
-                                                scroll_id,
+                                                prim_header_index: shadow_prim_header_index,
                                                 clip_task_address,
-                                                z,
                                                 segment_index: 0,
                                                 edge_flags: EdgeAaSegmentMask::empty(),
                                                 brush_flags: BrushFlags::empty(),
-                                                user_data: [
-                                                    shadow_uv_rect_address,
-                                                    (ShaderColorMode::Alpha as i32) << 16 |
-                                                    RasterizationSpace::Screen as i32,
-                                                    0,
-                                                ],
                                             };
 
                                             let content_instance = BrushInstance {
-                                                prim_address: prim_cache_address,
-                                                user_data: [
-                                                    content_uv_rect_address,
-                                                    (ShaderColorMode::ColorBitmap as i32) << 16 |
-                                                    RasterizationSpace::Screen as i32,
-                                                    0,
-                                                ],
-                                                ..shadow_instance
+                                                prim_header_index: content_prim_header_index,
+                                                clip_task_address,
+                                                segment_index: 0,
+                                                edge_flags: EdgeAaSegmentMask::empty(),
+                                                brush_flags: BrushFlags::empty(),
                                             };
 
                                             self.batch_list
@@ -856,22 +868,18 @@ impl AlphaBatchBuilder {
 
                                                 let cache_task_id = surface.resolve_render_task_id();
                                                 let cache_task_address = render_tasks.get_task_address(cache_task_id);
+                                                let prim_header_index = prim_headers.push(&prim_header, [
+                                                    cache_task_address.0 as i32,
+                                                    filter_mode,
+                                                    user_data,
+                                                ]);
 
                                                 let instance = BrushInstance {
-                                                    picture_address: task_address,
-                                                    prim_address: prim_cache_address,
-                                                    clip_chain_rect_index,
-                                                    scroll_id,
+                                                    prim_header_index,
                                                     clip_task_address,
-                                                    z,
                                                     segment_index: 0,
                                                     edge_flags: EdgeAaSegmentMask::empty(),
                                                     brush_flags: BrushFlags::empty(),
-                                                    user_data: [
-                                                        cache_task_address.0 as i32,
-                                                        filter_mode,
-                                                        user_data,
-                                                    ],
                                                 };
 
                                                 let batch = self.batch_list.get_suitable_batch(key, &task_relative_bounding_rect);
@@ -907,22 +915,18 @@ impl AlphaBatchBuilder {
                                 let batch = self.batch_list.get_suitable_batch(key, &task_relative_bounding_rect);
                                 let backdrop_task_address = render_tasks.get_task_address(backdrop_id);
                                 let source_task_address = render_tasks.get_task_address(cache_task_id);
+                                let prim_header_index = prim_headers.push(&prim_header, [
+                                    mode as u32 as i32,
+                                    backdrop_task_address.0 as i32,
+                                    source_task_address.0 as i32,
+                                ]);
 
                                 let instance = BrushInstance {
-                                    picture_address: task_address,
-                                    prim_address: prim_cache_address,
-                                    clip_chain_rect_index,
-                                    scroll_id,
+                                    prim_header_index,
                                     clip_task_address,
-                                    z,
                                     segment_index: 0,
                                     edge_flags: EdgeAaSegmentMask::empty(),
                                     brush_flags: BrushFlags::empty(),
-                                    user_data: [
-                                        mode as u32 as i32,
-                                        backdrop_task_address.0 as i32,
-                                        source_task_address.0 as i32,
-                                    ],
                                 };
 
                                 batch.push(PrimitiveInstance::from(instance));
@@ -950,23 +954,19 @@ impl AlphaBatchBuilder {
                                 let uv_rect_address = render_tasks[cache_task_id]
                                     .get_texture_address(gpu_cache)
                                     .as_int();
+                                let prim_header_index = prim_headers.push(&prim_header, [
+                                    uv_rect_address,
+                                    (ShaderColorMode::ColorBitmap as i32) << 16 |
+                                    RasterizationSpace::Screen as i32,
+                                    0,
+                                ]);
 
                                 let instance = BrushInstance {
-                                    picture_address: task_address,
-                                    prim_address: prim_cache_address,
-                                    clip_chain_rect_index,
-                                    scroll_id,
+                                    prim_header_index,
                                     clip_task_address,
-                                    z,
                                     segment_index: 0,
                                     edge_flags: EdgeAaSegmentMask::empty(),
                                     brush_flags: BrushFlags::empty(),
-                                    user_data: [
-                                        uv_rect_address,
-                                        (ShaderColorMode::ColorBitmap as i32) << 16 |
-                                        RasterizationSpace::Screen as i32,
-                                        0,
-                                    ],
                                 };
                                 batch.push(PrimitiveInstance::from(instance));
                                 false
@@ -986,7 +986,7 @@ impl AlphaBatchBuilder {
                                 gpu_cache,
                                 render_tasks,
                                 deferred_resolves,
-                                z_generator,
+                                prim_headers,
                             );
                         }
                     }
@@ -999,18 +999,21 @@ impl AlphaBatchBuilder {
                                     request.with_tile(tile.tile_offset),
                             ) {
                                 let prim_cache_address = gpu_cache.get_address(&tile.handle);
+                                let prim_header = PrimitiveHeader {
+                                    specific_prim_address: prim_cache_address,
+                                    local_rect: tile.local_rect,
+                                    local_clip_rect: tile.local_clip_rect,
+                                    ..prim_header
+                                };
+                                let prim_header_index = prim_headers.push(&prim_header, user_data);
+
                                 self.add_image_tile_to_batch(
                                     batch_kind,
                                     specified_blend_mode,
                                     textures,
-                                    clip_chain_rect_index,
+                                    prim_header_index,
                                     clip_task_address,
                                     &task_relative_bounding_rect,
-                                    prim_cache_address,
-                                    scroll_id,
-                                    task_address,
-                                    z,
-                                    user_data,
                                     tile.edge_flags
                                 );
                             }
@@ -1023,13 +1026,11 @@ impl AlphaBatchBuilder {
                             BrushBatchKind::LinearGradient,
                             specified_blend_mode,
                             &task_relative_bounding_rect,
-                            clip_chain_rect_index,
-                            scroll_id,
-                            task_address,
                             clip_task_address,
-                            z,
                             gpu_cache,
                             &mut self.batch_list,
+                            &prim_header,
+                            prim_headers,
                         );
                     }
                     BrushKind::RadialGradient { ref stops_handle, ref visible_tiles, .. } if !visible_tiles.is_empty() => {
@@ -1039,13 +1040,11 @@ impl AlphaBatchBuilder {
                             BrushBatchKind::RadialGradient,
                             specified_blend_mode,
                             &task_relative_bounding_rect,
-                            clip_chain_rect_index,
-                            scroll_id,
-                            task_address,
                             clip_task_address,
-                            z,
                             gpu_cache,
                             &mut self.batch_list,
+                            &prim_header,
+                            prim_headers,
                         );
                     }
                     _ => {
@@ -1054,6 +1053,8 @@ impl AlphaBatchBuilder {
                                 gpu_cache,
                                 deferred_resolves,
                         ) {
+                            let prim_header_index = prim_headers.push(&prim_header, user_data);
+
                             self.add_brush_to_batch(
                                 brush,
                                 prim_metadata,
@@ -1061,16 +1062,11 @@ impl AlphaBatchBuilder {
                                 specified_blend_mode,
                                 non_segmented_blend_mode,
                                 textures,
-                                clip_chain_rect_index,
+                                prim_header_index,
                                 clip_task_address,
                                 &task_relative_bounding_rect,
-                                prim_cache_address,
-                                scroll_id,
-                                task_address,
                                 transform_kind,
-                                z,
                                 render_tasks,
-                                user_data,
                             );
                         }
                     }
@@ -1080,17 +1076,13 @@ impl AlphaBatchBuilder {
                 let text_cpu =
                     &ctx.prim_store.cpu_text_runs[prim_metadata.cpu_prim_index.0];
 
-                let font = text_cpu.get_font(
-                    ctx.device_pixel_scale,
-                    scroll_node.transform,
-                );
-                let subpx_dir = font.get_subpx_dir();
+                let subpx_dir = text_cpu.used_font.get_subpx_dir();
 
                 let glyph_fetch_buffer = &mut self.glyph_fetch_buffer;
                 let batch_list = &mut self.batch_list;
 
                 ctx.resource_cache.fetch_glyphs(
-                    font,
+                    text_cpu.used_font.clone(),
                     &text_cpu.glyph_keys,
                     glyph_fetch_buffer,
                     gpu_cache,
@@ -1117,7 +1109,7 @@ impl AlphaBatchBuilder {
                         let (blend_mode, color_mode) = match glyph_format {
                             GlyphFormat::Subpixel |
                             GlyphFormat::TransformedSubpixel => {
-                                if text_cpu.font.bg_color.a != 0 {
+                                if text_cpu.used_font.bg_color.a != 0 {
                                     (
                                         BlendMode::SubpixelWithBgColor,
                                         ShaderColorMode::FromRenderPassMode,
@@ -1129,7 +1121,7 @@ impl AlphaBatchBuilder {
                                     )
                                 } else {
                                     (
-                                        BlendMode::SubpixelConstantTextColor(text_cpu.font.color.into()),
+                                        BlendMode::SubpixelConstantTextColor(text_cpu.used_font.color.into()),
                                         ShaderColorMode::SubpixelConstantTextColor,
                                     )
                                 }
@@ -1155,15 +1147,11 @@ impl AlphaBatchBuilder {
                             }
                         };
 
+                        let prim_header_index = prim_headers.push(&prim_header, [0; 3]);
                         let key = BatchKey::new(kind, blend_mode, textures);
                         let batch = batch_list.get_suitable_batch(key, &task_relative_bounding_rect);
                         let base_instance = GlyphInstance::new(
-                            prim_cache_address,
-                            task_address,
-                            clip_task_address,
-                            clip_chain_rect_index,
-                            scroll_id,
-                            z,
+                            prim_header_index,
                         );
 
                         for glyph in glyphs {
@@ -1185,27 +1173,17 @@ impl AlphaBatchBuilder {
         batch_kind: BrushBatchKind,
         blend_mode: BlendMode,
         textures: BatchTextures,
-        clip_chain_rect_index: ClipChainRectIndex,
+        prim_header_index: PrimitiveHeaderIndex,
         clip_task_address: RenderTaskAddress,
         task_relative_bounding_rect: &DeviceIntRect,
-        prim_cache_address: GpuCacheAddress,
-        scroll_id: ClipScrollNodeIndex,
-        task_address: RenderTaskAddress,
-        z: ZBufferId,
-        user_data: [i32; 3],
         edge_flags: EdgeAaSegmentMask,
     ) {
         let base_instance = BrushInstance {
-            picture_address: task_address,
-            prim_address: prim_cache_address,
-            clip_chain_rect_index,
-            scroll_id,
+            prim_header_index,
             clip_task_address,
-            z,
             segment_index: 0,
             edge_flags,
             brush_flags: BrushFlags::PERSPECTIVE_INTERPOLATION,
-            user_data,
         };
 
         self.batch_list.add_bounding_rect(task_relative_bounding_rect);
@@ -1227,28 +1205,18 @@ impl AlphaBatchBuilder {
         alpha_blend_mode: BlendMode,
         non_segmented_blend_mode: BlendMode,
         textures: BatchTextures,
-        clip_chain_rect_index: ClipChainRectIndex,
+        prim_header_index: PrimitiveHeaderIndex,
         clip_task_address: RenderTaskAddress,
         task_relative_bounding_rect: &DeviceIntRect,
-        prim_cache_address: GpuCacheAddress,
-        scroll_id: ClipScrollNodeIndex,
-        task_address: RenderTaskAddress,
         transform_kind: TransformedRectKind,
-        z: ZBufferId,
         render_tasks: &RenderTaskTree,
-        user_data: [i32; 3],
     ) {
         let base_instance = BrushInstance {
-            picture_address: task_address,
-            prim_address: prim_cache_address,
-            clip_chain_rect_index,
-            scroll_id,
+            prim_header_index,
             clip_task_address,
-            z,
             segment_index: 0,
             edge_flags: EdgeAaSegmentMask::all(),
             brush_flags: BrushFlags::PERSPECTIVE_INTERPOLATION,
-            user_data,
         };
 
         self.batch_list.add_bounding_rect(task_relative_bounding_rect);
@@ -1326,13 +1294,11 @@ fn add_gradient_tiles(
     kind: BrushBatchKind,
     blend_mode: BlendMode,
     task_relative_bounding_rect: &DeviceIntRect,
-    clip_chain_rect_index: ClipChainRectIndex,
-    scroll_id: ClipScrollNodeIndex,
-    task_address: RenderTaskAddress,
     clip_task_address: RenderTaskAddress,
-    z: ZBufferId,
     gpu_cache: &GpuCache,
     batch_list: &mut BatchList,
+    base_prim_header: &PrimitiveHeader,
+    prim_headers: &mut PrimitiveHeaders,
 ) {
     batch_list.add_bounding_rect(task_relative_bounding_rect);
     let batch = batch_list.get_suitable_batch(
@@ -1346,24 +1312,22 @@ fn add_gradient_tiles(
 
     let user_data = [stops_handle.as_int(gpu_cache), 0, 0];
 
-    let base_instance = BrushInstance {
-        picture_address: task_address,
-        prim_address: GpuCacheAddress::invalid(),
-        clip_chain_rect_index,
-        scroll_id,
-        clip_task_address,
-        z,
-        segment_index: 0,
-        edge_flags: EdgeAaSegmentMask::all(),
-        brush_flags: BrushFlags::PERSPECTIVE_INTERPOLATION,
-        user_data,
-    };
-
     for tile in visible_tiles {
+        let prim_header = PrimitiveHeader {
+            specific_prim_address: gpu_cache.get_address(&tile.handle),
+            local_rect: tile.local_rect,
+            local_clip_rect: tile.local_clip_rect,
+            ..*base_prim_header
+        };
+        let prim_header_index = prim_headers.push(&prim_header, user_data);
+
         batch.push(PrimitiveInstance::from(
             BrushInstance {
-                prim_address: gpu_cache.get_address(&tile.handle),
-                ..base_instance
+                prim_header_index,
+                clip_task_address,
+                segment_index: 0,
+                edge_flags: EdgeAaSegmentMask::all(),
+                brush_flags: BrushFlags::PERSPECTIVE_INTERPOLATION,
             }
         ));
     }
@@ -1783,7 +1747,7 @@ impl ClipBatcher {
     ) {
         let instance = ClipMaskInstance {
             render_task_address: task_address,
-            scroll_node_data_index: ClipScrollNodeIndex(0),
+            transform_id: TransformPaletteId::identity(),
             segment: 0,
             clip_data_address,
             resource_address: GpuCacheAddress::invalid(),
@@ -1800,12 +1764,13 @@ impl ClipBatcher {
         resource_cache: &ResourceCache,
         gpu_cache: &GpuCache,
         clip_store: &ClipStore,
+        transforms: &TransformPalette,
     ) {
         let mut coordinate_system_id = coordinate_system_id;
         for work_item in clips.iter() {
             let instance = ClipMaskInstance {
                 render_task_address: task_address,
-                scroll_node_data_index: work_item.scroll_node_data_index,
+                transform_id: transforms.get_id(work_item.transform_index),
                 segment: 0,
                 clip_data_address: GpuCacheAddress::invalid(),
                 resource_address: GpuCacheAddress::invalid(),

gfx/webrender/src/clip.rs

@@ -7,11 +7,11 @@ use api::{ImageRendering, LayoutRect, LayoutSize, LayoutPoint, LayoutVector2D, L
 use api::{BoxShadowClipMode, LayoutToWorldScale, LineOrientation, LineStyle};
 use border::{ensure_no_corner_overlap};
 use box_shadow::{BLUR_SAMPLE_SCALE, BoxShadowClipSource, BoxShadowCacheKey};
-use clip_scroll_tree::{ClipChainIndex, CoordinateSystemId};
+use clip_scroll_tree::{ClipChainIndex, CoordinateSystemId, TransformIndex};
 use ellipse::Ellipse;
 use freelist::{FreeList, FreeListHandle, WeakFreeListHandle};
 use gpu_cache::{GpuCache, GpuCacheHandle, ToGpuBlocks};
-use gpu_types::{BoxShadowStretchMode, ClipScrollNodeIndex};
+use gpu_types::{BoxShadowStretchMode};
 use prim_store::{ClipData, ImageMaskData};
 use render_task::to_cache_size;
 use resource_cache::{ImageRequest, ResourceCache};
@@ -625,7 +625,7 @@ impl Iterator for ClipChainNodeIter {
 #[cfg_attr(feature = "capture", derive(Serialize))]
 #[cfg_attr(feature = "replay", derive(Deserialize))]
 pub struct ClipWorkItem {
-    pub scroll_node_data_index: ClipScrollNodeIndex,
+    pub transform_index: TransformIndex,
     pub clip_sources: ClipSourcesWeakHandle,
     pub coordinate_system_id: CoordinateSystemId,
 }

gfx/webrender/src/clip_scroll_node.rs

@@ -7,10 +7,10 @@ use api::{LayoutVector2D, LayoutTransform, PipelineId, PropertyBinding};
 use api::{ScrollClamping, ScrollLocation, ScrollSensitivity, StickyOffsetBounds};
 use clip::{ClipChain, ClipChainNode, ClipSourcesHandle, ClipStore, ClipWorkItem};
 use clip_scroll_tree::{ClipChainIndex, ClipScrollNodeIndex, CoordinateSystemId};
-use clip_scroll_tree::TransformUpdateState;
+use clip_scroll_tree::{TransformUpdateState, TransformIndex};
 use euclid::SideOffsets2D;
 use gpu_cache::GpuCache;
-use gpu_types::{ClipScrollNodeIndex as GPUClipScrollNodeIndex, ClipScrollNodeData};
+use gpu_types::{TransformData, TransformPalette};
 use resource_cache::ResourceCache;
 use scene::SceneProperties;
 use util::{LayoutToWorldFastTransform, LayoutFastTransform};
@@ -46,9 +46,26 @@ impl StickyFrameInfo {
 }
 
 #[derive(Debug)]
-pub enum NodeType {
+pub enum SpatialNodeKind {
+    /// A special kind of node that adjusts its position based on the position
+    /// of its parent node and a given set of sticky positioning offset bounds.
+    /// Sticky positioned is described in the CSS Positioned Layout Module Level 3 here:
+    /// https://www.w3.org/TR/css-position-3/#sticky-pos
+    StickyFrame(StickyFrameInfo),
+
+    /// Transforms it's content, but doesn't clip it. Can also be adjusted
+    /// by scroll events or setting scroll offsets.
+    ScrollFrame(ScrollFrameInfo),
+
     /// A reference frame establishes a new coordinate space in the tree.
     ReferenceFrame(ReferenceFrameInfo),
+}
+
+#[derive(Debug)]
+pub enum NodeType {
+    Spatial {
+        kind: SpatialNodeKind,
+    },
 
     /// Other nodes just do clipping, but no transformation.
     Clip {
@@ -61,16 +78,6 @@ pub enum NodeType {
         clip_chain_node: Option<ClipChainNode>,
     },
 
-    /// Transforms it's content, but doesn't clip it. Can also be adjusted
-    /// by scroll events or setting scroll offsets.
-    ScrollFrame(ScrollFrameInfo),
-
-    /// A special kind of node that adjusts its position based on the position
-    /// of its parent node and a given set of sticky positioning offset bounds.
-    /// Sticky positioned is described in the CSS Positioned Layout Module Level 3 here:
-    /// https://www.w3.org/TR/css-position-3/#sticky-pos
-    StickyFrame(StickyFrameInfo),
-
     /// An empty node, used to pad the ClipScrollTree's array of nodes so that
     /// we can immediately use each assigned ClipScrollNodeIndex. After display
     /// list flattening this node type should never be used.
@@ -80,7 +87,7 @@ pub enum NodeType {
 impl NodeType {
     fn is_reference_frame(&self) -> bool {
         match *self {
-            NodeType::ReferenceFrame(_) => true,
+            NodeType::Spatial { kind: SpatialNodeKind::ReferenceFrame(_), .. } => true,
             _ => false,
         }
     }
@@ -126,16 +133,18 @@ pub struct ClipScrollNode {
     /// reference frame transforms.
     pub coordinate_system_relative_transform: LayoutFastTransform,
 
-    /// A linear ID / index of this clip-scroll node. Used as a reference to
-    /// pass to shaders, to allow them to fetch a given clip-scroll node.
-    pub node_data_index: GPUClipScrollNodeIndex,
+    /// The index of the spatial node that provides positioning information for this node.
+    /// For reference frames, scroll and sticky frames it is a unique identfier.
+    /// For clip nodes, this is the nearest ancestor spatial node.
+    pub transform_index: TransformIndex,
 }
 
 impl ClipScrollNode {
     pub fn new(
         pipeline_id: PipelineId,
         parent_index: Option<ClipScrollNodeIndex>,
-        node_type: NodeType
+        node_type: NodeType,
+        transform_index: TransformIndex,
     ) -> Self {
         ClipScrollNode {
             world_viewport_transform: LayoutToWorldFastTransform::identity(),
@@ -148,12 +157,17 @@ impl ClipScrollNode {
             invertible: true,
             coordinate_system_id: CoordinateSystemId(0),
             coordinate_system_relative_transform: LayoutFastTransform::identity(),
-            node_data_index: GPUClipScrollNodeIndex(0),
+            transform_index,
         }
     }
 
     pub fn empty() -> ClipScrollNode {
-        Self::new(PipelineId::dummy(), None, NodeType::Empty)
+        Self::new(
+            PipelineId::dummy(),
+            None,
+            NodeType::Empty,
+            TransformIndex(0),
+        )
     }
 
     pub fn new_scroll_frame(
@@ -163,18 +177,26 @@ impl ClipScrollNode {
         frame_rect: &LayoutRect,
         content_size: &LayoutSize,
         scroll_sensitivity: ScrollSensitivity,
+        transform_index: TransformIndex,
     ) -> Self {
-        let node_type = NodeType::ScrollFrame(ScrollFrameInfo::new(
-            *frame_rect,
-            scroll_sensitivity,
-            LayoutSize::new(
-                (content_size.width - frame_rect.size.width).max(0.0),
-                (content_size.height - frame_rect.size.height).max(0.0)
-            ),
-            external_id,
-        ));
+        let node_type = NodeType::Spatial {
+            kind: SpatialNodeKind::ScrollFrame(ScrollFrameInfo::new(
+                *frame_rect,
+                scroll_sensitivity,
+                LayoutSize::new(
+                    (content_size.width - frame_rect.size.width).max(0.0),
+                    (content_size.height - frame_rect.size.height).max(0.0)
+                ),
+                external_id,
+            )),
+        };
 
-        Self::new(pipeline_id, Some(parent_index), node_type)
+        Self::new(
+            pipeline_id,
+            Some(parent_index),
+            node_type,
+            transform_index,
+        )
     }
 
     pub fn new_reference_frame(
@@ -183,6 +205,7 @@ impl ClipScrollNode {
         source_perspective: Option<LayoutTransform>,
         origin_in_parent_reference_frame: LayoutVector2D,
         pipeline_id: PipelineId,
+        transform_index: TransformIndex,
     ) -> Self {
         let identity = LayoutTransform::identity();
         let source_perspective = source_perspective.map_or_else(
@@ -194,16 +217,31 @@ impl ClipScrollNode {
             origin_in_parent_reference_frame,
             invertible: true,
         };
-        Self::new(pipeline_id, parent_index, NodeType::ReferenceFrame(info))
+        Self::new(
+            pipeline_id,
+            parent_index,
+            NodeType::Spatial {
+                kind: SpatialNodeKind::ReferenceFrame(info),
+            },
+            transform_index,
+        )
     }
 
     pub fn new_sticky_frame(
         parent_index: ClipScrollNodeIndex,
         sticky_frame_info: StickyFrameInfo,
         pipeline_id: PipelineId,
+        transform_index: TransformIndex,
     ) -> Self {
-        let node_type = NodeType::StickyFrame(sticky_frame_info);
-        Self::new(pipeline_id, Some(parent_index), node_type)
+        let node_type = NodeType::Spatial {
+            kind: SpatialNodeKind::StickyFrame(sticky_frame_info),
+        };
+        Self::new(
+            pipeline_id,
+            Some(parent_index),
+            node_type,
+            transform_index,
+        )
     }
 
 
@@ -213,7 +251,7 @@ impl ClipScrollNode {
 
     pub fn apply_old_scrolling_state(&mut self, old_scroll_info: &ScrollFrameInfo) {
         match self.node_type {
-            NodeType::ScrollFrame(ref mut scrolling) => {
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(ref mut scrolling), .. } => {
                 *scrolling = scrolling.combine_with_old_scroll_info(old_scroll_info);
             }
             _ if old_scroll_info.offset != LayoutVector2D::zero() => {
@@ -229,7 +267,7 @@ impl ClipScrollNode {
         let scrollable_height = scrollable_size.height;
 
         let scrolling = match self.node_type {
-            NodeType::ScrollFrame(ref mut scrolling) => scrolling,
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(ref mut scrolling), .. } => scrolling,
             _ => {
                 warn!("Tried to scroll a non-scroll node.");
                 return false;
@@ -265,29 +303,32 @@ impl ClipScrollNode {
         self.world_viewport_transform = LayoutToWorldFastTransform::identity();
     }
 
-    pub fn push_gpu_node_data(&mut self, node_data: &mut Vec<ClipScrollNodeData>) {
-        if !self.invertible {
-            node_data.push(ClipScrollNodeData::invalid());
-            return;
-        }
-
-        let inv_transform = match self.world_content_transform.inverse() {
-            Some(inverted) => inverted.to_transform(),
-            None => {
-                node_data.push(ClipScrollNodeData::invalid());
+    pub fn push_gpu_data(
+        &mut self,
+        transform_palette: &mut TransformPalette,
+    ) {
+        if let NodeType::Spatial { .. } = self.node_type {
+            if !self.invertible {
+                transform_palette.set(self.transform_index, TransformData::invalid());
                 return;
             }
-        };
 
-        let data = ClipScrollNodeData {
-            transform: self.world_content_transform.into(),
-            inv_transform,
-            transform_kind: self.transform_kind as u32 as f32,
-            padding: [0.0; 3],
-        };
+            let inv_transform = match self.world_content_transform.inverse() {
+                Some(inverted) => inverted.to_transform(),
+                None => {
+                    transform_palette.set(self.transform_index, TransformData::invalid());
+                    return;
+                }
+            };
 
-        // Write the data that will be made available to the GPU for this node.
-        node_data.push(data);
+            let data = TransformData {
+                transform: self.world_content_transform.into(),
+                inv_transform,
+            };
+
+            // Write the data that will be made available to the GPU for this node.
+            transform_palette.set(self.transform_index, data);
+        }
     }
 
     pub fn update(
@@ -320,7 +361,7 @@ impl ClipScrollNode {
         // For non-reference-frames we assume that they will produce only additional
         // translations which should be invertible.
         match self.node_type {
-            NodeType::ReferenceFrame(info) if !info.invertible => {
+            NodeType::Spatial { kind: SpatialNodeKind::ReferenceFrame(info), .. } if !info.invertible => {
                 self.mark_uninvertible();
                 return;
             }
@@ -347,7 +388,7 @@ impl ClipScrollNode {
         clip_chains: &mut [ClipChain],
     ) {
         let (clip_sources_handle, clip_chain_index, stored_clip_chain_node) = match self.node_type {
-            NodeType::Clip { ref handle, clip_chain_index, ref mut clip_chain_node } =>
+            NodeType::Clip { ref handle, clip_chain_index, ref mut clip_chain_node, .. } =>
                 (handle, clip_chain_index, clip_chain_node),
             _ => {
                 self.invertible = true;
@@ -378,7 +419,7 @@ impl ClipScrollNode {
 
         let new_node = ClipChainNode {
             work_item: ClipWorkItem {
-                scroll_node_data_index: self.node_data_index,
+                transform_index: self.transform_index,
                 clip_sources: clip_sources_handle.weak(),
                 coordinate_system_id: state.current_coordinate_system_id,
             },
@@ -442,9 +483,8 @@ impl ClipScrollNode {
         self.coordinate_system_relative_transform =
             state.coordinate_system_relative_transform.offset(added_offset);
 
-        match self.node_type {
-            NodeType::StickyFrame(ref mut info) => info.current_offset = sticky_offset,
-            _ => {},
+        if let NodeType::Spatial { kind: SpatialNodeKind::StickyFrame(ref mut info), .. } = self.node_type {
+            info.current_offset = sticky_offset;
         }
 
         self.coordinate_system_id = state.current_coordinate_system_id;
@@ -457,7 +497,7 @@ impl ClipScrollNode {
         scene_properties: &SceneProperties,
     ) {
         let info = match self.node_type {
-            NodeType::ReferenceFrame(ref mut info) => info,
+            NodeType::Spatial { kind: SpatialNodeKind::ReferenceFrame(ref mut info), .. } => info,
             _ => unreachable!("Called update_transform_for_reference_frame on non-ReferenceFrame"),
         };
 
@@ -505,7 +545,7 @@ impl ClipScrollNode {
         viewport_rect: &LayoutRect,
     ) -> LayoutVector2D {
         let info = match self.node_type {
-            NodeType::StickyFrame(ref info) => info,
+            NodeType::Spatial { kind: SpatialNodeKind::StickyFrame(ref info), .. } => info,
             _ => return LayoutVector2D::zero(),
         };
 
@@ -619,45 +659,48 @@ impl ClipScrollNode {
         // between us and the parent reference frame. If we are a reference frame,
         // we need to reset both these values.
         match self.node_type {
-            NodeType::ReferenceFrame(ref info) => {
-                state.parent_reference_frame_transform = self.world_viewport_transform;
-                state.parent_accumulated_scroll_offset = LayoutVector2D::zero();
-                state.coordinate_system_relative_transform =
-                    self.coordinate_system_relative_transform.clone();
-                let translation = -info.origin_in_parent_reference_frame;
-                state.nearest_scrolling_ancestor_viewport =
-                    state.nearest_scrolling_ancestor_viewport
-                       .translate(&translation);
+            NodeType::Spatial { ref kind, .. } => {
+                match *kind {
+                    SpatialNodeKind::StickyFrame(ref info) => {
+                        // We don't translate the combined rect by the sticky offset, because sticky
+                        // offsets actually adjust the node position itself, whereas scroll offsets
+                        // only apply to contents inside the node.
+                        state.parent_accumulated_scroll_offset =
+                            info.current_offset + state.parent_accumulated_scroll_offset;
+                    }
+                    SpatialNodeKind::ScrollFrame(ref scrolling) => {
+                        state.parent_accumulated_scroll_offset =
+                            scrolling.offset + state.parent_accumulated_scroll_offset;
+                        state.nearest_scrolling_ancestor_offset = scrolling.offset;
+                        state.nearest_scrolling_ancestor_viewport = scrolling.viewport_rect;
+                    }
+                    SpatialNodeKind::ReferenceFrame(ref info) => {
+                        state.parent_reference_frame_transform = self.world_viewport_transform;
+                        state.parent_accumulated_scroll_offset = LayoutVector2D::zero();
+                        state.coordinate_system_relative_transform =
+                            self.coordinate_system_relative_transform.clone();
+                        let translation = -info.origin_in_parent_reference_frame;
+                        state.nearest_scrolling_ancestor_viewport =
+                            state.nearest_scrolling_ancestor_viewport
+                               .translate(&translation);
+                    }
+                }
             }
             NodeType::Clip{ .. } => { }
-            NodeType::ScrollFrame(ref scrolling) => {
-                state.parent_accumulated_scroll_offset =
-                    scrolling.offset + state.parent_accumulated_scroll_offset;
-                state.nearest_scrolling_ancestor_offset = scrolling.offset;
-                state.nearest_scrolling_ancestor_viewport = scrolling.viewport_rect;
-            }
-            NodeType::StickyFrame(ref info) => {
-                // We don't translate the combined rect by the sticky offset, because sticky
-                // offsets actually adjust the node position itself, whereas scroll offsets
-                // only apply to contents inside the node.
-                state.parent_accumulated_scroll_offset =
-                    info.current_offset + state.parent_accumulated_scroll_offset;
-            }
             NodeType::Empty => unreachable!("Empty node remaining in ClipScrollTree."),
         }
     }
 
     pub fn scrollable_size(&self) -> LayoutSize {
         match self.node_type {
-           NodeType:: ScrollFrame(state) => state.scrollable_size,
+           NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(state), .. } => state.scrollable_size,
             _ => LayoutSize::zero(),
         }
     }
 
-
     pub fn scroll(&mut self, scroll_location: ScrollLocation) -> bool {
         let scrolling = match self.node_type {
-            NodeType::ScrollFrame(ref mut scrolling) => scrolling,
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(ref mut scrolling), .. } => scrolling,
             _ => return false,
         };
 
@@ -707,14 +750,14 @@ impl ClipScrollNode {
 
     pub fn scroll_offset(&self) -> LayoutVector2D {
         match self.node_type {
-            NodeType::ScrollFrame(ref scrolling) => scrolling.offset,
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(ref scrolling), .. } => scrolling.offset,
             _ => LayoutVector2D::zero(),
         }
     }
 
     pub fn matches_external_id(&self, external_id: ExternalScrollId) -> bool {
         match self.node_type {
-            NodeType::ScrollFrame(info) if info.external_id == Some(external_id) => true,
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(info), .. } if info.external_id == Some(external_id) => true,
             _ => false,
         }
     }

gfx/webrender/src/clip_scroll_tree.rs

@@ -4,11 +4,11 @@
 
 use api::{DeviceIntRect, DevicePixelScale, ExternalScrollId, LayoutPoint, LayoutRect, LayoutVector2D};
 use api::{PipelineId, ScrollClamping, ScrollLocation, ScrollNodeState};
-use api::WorldPoint;
+use api::{LayoutSize, LayoutTransform, PropertyBinding, ScrollSensitivity, WorldPoint};
 use clip::{ClipChain, ClipSourcesHandle, ClipStore};
-use clip_scroll_node::{ClipScrollNode, NodeType, ScrollFrameInfo, StickyFrameInfo};
+use clip_scroll_node::{ClipScrollNode, NodeType, SpatialNodeKind, ScrollFrameInfo, StickyFrameInfo};
 use gpu_cache::GpuCache;
-use gpu_types::{ClipScrollNodeIndex as GPUClipScrollNodeIndex, ClipScrollNodeData};
+use gpu_types::TransformPalette;
 use internal_types::{FastHashMap, FastHashSet};
 use print_tree::{PrintTree, PrintTreePrinter};
 use resource_cache::ResourceCache;
@@ -29,6 +29,15 @@ pub struct CoordinateSystemId(pub u32);
 #[derive(Debug, Copy, Clone, Eq, Hash, PartialEq)]
 pub struct ClipScrollNodeIndex(pub usize);
 
+// Used to index the smaller subset of nodes in the CST that define
+// new transform / positioning.
+// TODO(gw): In the future if we split the CST into a positioning and
+//           clipping tree, this can be tidied up a bit.
+#[derive(Copy, Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct TransformIndex(pub u32);
+
 const ROOT_REFERENCE_FRAME_INDEX: ClipScrollNodeIndex = ClipScrollNodeIndex(0);
 const TOPMOST_SCROLL_NODE_INDEX: ClipScrollNodeIndex = ClipScrollNodeIndex(1);
 
@@ -70,14 +79,13 @@ pub struct ClipScrollTree {
 
     pub pending_scroll_offsets: FastHashMap<ExternalScrollId, (LayoutPoint, ScrollClamping)>,
 
-    /// The current frame id, used for giving a unique id to all new dynamically
-    /// added frames and clips. The ClipScrollTree increments this by one every
-    /// time a new dynamic frame is created.
-    current_new_node_item: u64,
-
     /// A set of pipelines which should be discarded the next time this
     /// tree is drained.
     pub pipelines_to_discard: FastHashSet<PipelineId>,
+
+    /// The number of nodes in the CST that are spatial. Currently, this is all
+    /// nodes that are not clip nodes.
+    spatial_node_count: usize,
 }
 
 #[derive(Clone)]
@@ -112,8 +120,8 @@ impl ClipScrollTree {
             clip_chains_descriptors: Vec::new(),
             clip_chains: vec![ClipChain::empty(&DeviceIntRect::zero())],
             pending_scroll_offsets: FastHashMap::default(),
-            current_new_node_item: 1,
             pipelines_to_discard: FastHashSet::default(),
+            spatial_node_count: 0,
         }
     }
 
@@ -136,7 +144,7 @@ impl ClipScrollTree {
     pub fn get_scroll_node_state(&self) -> Vec<ScrollNodeState> {
         let mut result = vec![];
         for node in &self.nodes {
-            if let NodeType::ScrollFrame(info) = node.node_type {
+            if let NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(info), .. } = node.node_type {
                 if let Some(id) = info.external_id {
                     result.push(ScrollNodeState { id, scroll_offset: info.offset })
                 }
@@ -146,8 +154,6 @@ impl ClipScrollTree {
     }
 
     pub fn drain(&mut self) -> ScrollStates {
-        self.current_new_node_item = 1;
-
         let mut scroll_states = FastHashMap::default();
         for old_node in &mut self.nodes.drain(..) {
             if self.pipelines_to_discard.contains(&old_node.pipeline_id) {
@@ -155,13 +161,14 @@ impl ClipScrollTree {
             }
 
             match old_node.node_type {
-                NodeType::ScrollFrame(info) if info.external_id.is_some() => {
+                NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(info), .. } if info.external_id.is_some() => {
                     scroll_states.insert(info.external_id.unwrap(), info);
                 }
                 _ => {}
             }
         }
 
+        self.spatial_node_count = 0;
         self.pipelines_to_discard.clear();
         self.clip_chains = vec![ClipChain::empty(&DeviceIntRect::zero())];
         self.clip_chains_descriptors.clear();
@@ -195,7 +202,7 @@ impl ClipScrollTree {
 
         let node = &self.nodes[index.0];
         match node.node_type {
-            NodeType::ScrollFrame(state) if state.sensitive_to_input_events() => index,
+            NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(state), .. } if state.sensitive_to_input_events() => index,
             _ => self.find_nearest_scrolling_ancestor(node.parent)
         }
     }
@@ -220,40 +227,41 @@ impl ClipScrollTree {
         resource_cache: &mut ResourceCache,
         gpu_cache: &mut GpuCache,
         pan: WorldPoint,
-        node_data: &mut Vec<ClipScrollNodeData>,
         scene_properties: &SceneProperties,
-    ) {
-        if self.nodes.is_empty() {
-            return;
+    ) -> TransformPalette {
+        let mut transform_palette = TransformPalette::new(self.spatial_node_count);
+
+        if !self.nodes.is_empty() {
+            self.clip_chains[0] = ClipChain::empty(screen_rect);
+
+            let root_reference_frame_index = self.root_reference_frame_index();
+            let mut state = TransformUpdateState {
+                parent_reference_frame_transform: LayoutVector2D::new(pan.x, pan.y).into(),
+                parent_accumulated_scroll_offset: LayoutVector2D::zero(),
+                nearest_scrolling_ancestor_offset: LayoutVector2D::zero(),
+                nearest_scrolling_ancestor_viewport: LayoutRect::zero(),
+                parent_clip_chain_index: ClipChainIndex(0),
+                current_coordinate_system_id: CoordinateSystemId::root(),
+                coordinate_system_relative_transform: LayoutFastTransform::identity(),
+                invertible: true,
+            };
+            let mut next_coordinate_system_id = state.current_coordinate_system_id.next();
+            self.update_node(
+                root_reference_frame_index,
+                &mut state,
+                &mut next_coordinate_system_id,
+                device_pixel_scale,
+                clip_store,
+                resource_cache,
+                gpu_cache,
+                &mut transform_palette,
+                scene_properties,
+            );
+
+            self.build_clip_chains(screen_rect);
         }
 
-        self.clip_chains[0] = ClipChain::empty(screen_rect);
-
-        let root_reference_frame_index = self.root_reference_frame_index();
-        let mut state = TransformUpdateState {
-            parent_reference_frame_transform: LayoutVector2D::new(pan.x, pan.y).into(),
-            parent_accumulated_scroll_offset: LayoutVector2D::zero(),
-            nearest_scrolling_ancestor_offset: LayoutVector2D::zero(),
-            nearest_scrolling_ancestor_viewport: LayoutRect::zero(),
-            parent_clip_chain_index: ClipChainIndex(0),
-            current_coordinate_system_id: CoordinateSystemId::root(),
-            coordinate_system_relative_transform: LayoutFastTransform::identity(),
-            invertible: true,
-        };
-        let mut next_coordinate_system_id = state.current_coordinate_system_id.next();
-        self.update_node(
-            root_reference_frame_index,
-            &mut state,
-            &mut next_coordinate_system_id,
-            device_pixel_scale,
-            clip_store,
-            resource_cache,
-            gpu_cache,
-            node_data,
-            scene_properties,
-        );
-
-        self.build_clip_chains(screen_rect);
+        transform_palette
     }
 
     fn update_node(
@@ -265,7 +273,7 @@ impl ClipScrollTree {
         clip_store: &mut ClipStore,
         resource_cache: &mut ResourceCache,
         gpu_cache: &mut GpuCache,
-        gpu_node_data: &mut Vec<ClipScrollNodeData>,
+        transform_palette: &mut TransformPalette,
         scene_properties: &SceneProperties,
     ) {
         // TODO(gw): This is an ugly borrow check workaround to clone these.
@@ -277,9 +285,6 @@ impl ClipScrollTree {
                 None => return,
             };
 
-            // We set this early so that we can use it to populate the ClipChain.
-            node.node_data_index = GPUClipScrollNodeIndex(gpu_node_data.len() as u32);
-
             node.update(
                 &mut state,
                 next_coordinate_system_id,
@@ -291,7 +296,7 @@ impl ClipScrollTree {
                 &mut self.clip_chains,
             );
 
-            node.push_gpu_node_data(gpu_node_data);
+            node.push_gpu_data(transform_palette);
 
             if node.children.is_empty() {
                 return;
@@ -310,7 +315,7 @@ impl ClipScrollTree {
                 clip_store,
                 resource_cache,
                 gpu_cache,
-                gpu_node_data,
+                transform_palette,
                 scene_properties,
             );
         }
@@ -346,7 +351,7 @@ impl ClipScrollTree {
     pub fn finalize_and_apply_pending_scroll_offsets(&mut self, old_states: ScrollStates) {
         for node in &mut self.nodes {
             let external_id = match node.node_type {
-                NodeType::ScrollFrame(ScrollFrameInfo { external_id: Some(id), ..} ) => id,
+                NodeType::Spatial { kind: SpatialNodeKind::ScrollFrame(ScrollFrameInfo { external_id: Some(id), ..} ), .. } => id,
                 _ => continue,
             };
 
@@ -360,6 +365,13 @@ impl ClipScrollTree {
         }
     }
 
+    // Generate the next valid TransformIndex for the CST.
+    fn next_transform_index(&mut self) -> TransformIndex {
+        let transform_index = TransformIndex(self.spatial_node_count as u32);
+        self.spatial_node_count += 1;
+        transform_index
+    }
+
     pub fn add_clip_node(
         &mut self,
         index: ClipScrollNodeIndex,
@@ -368,12 +380,65 @@ impl ClipScrollTree {
         pipeline_id: PipelineId,
     )  -> ClipChainIndex {
         let clip_chain_index = self.allocate_clip_chain();
-        let node_type = NodeType::Clip { handle, clip_chain_index, clip_chain_node: None };
-        let node = ClipScrollNode::new(pipeline_id, Some(parent_index), node_type);
+        let transform_index = self.nodes[parent_index.0].transform_index;
+
+        let node_type = NodeType::Clip {
+            handle,
+            clip_chain_index,
+            clip_chain_node: None,
+        };
+        let node = ClipScrollNode::new(
+            pipeline_id,
+            Some(parent_index),
+            node_type,
+            transform_index,
+        );
         self.add_node(node, index);
         clip_chain_index
     }
 
+    pub fn add_scroll_frame(
+        &mut self,
+        index: ClipScrollNodeIndex,
+        parent_index: ClipScrollNodeIndex,
+        external_id: Option<ExternalScrollId>,
+        pipeline_id: PipelineId,
+        frame_rect: &LayoutRect,
+        content_size: &LayoutSize,
+        scroll_sensitivity: ScrollSensitivity,
+    ) {
+        let node = ClipScrollNode::new_scroll_frame(
+            pipeline_id,
+            parent_index,
+            external_id,
+            frame_rect,
+            content_size,
+            scroll_sensitivity,
+            self.next_transform_index(),
+        );
+        self.add_node(node, index);
+    }
+
+    pub fn add_reference_frame(
+        &mut self,
+        index: ClipScrollNodeIndex,
+        parent_index: Option<ClipScrollNodeIndex>,
+        source_transform: Option<PropertyBinding<LayoutTransform>>,
+        source_perspective: Option<LayoutTransform>,
+        origin_in_parent_reference_frame: LayoutVector2D,
+        pipeline_id: PipelineId,
+    ) {
+        let node = ClipScrollNode::new_reference_frame(
+            parent_index,
+            source_transform,
+            source_perspective,
+            origin_in_parent_reference_frame,
+            pipeline_id,
+            self.next_transform_index(),
+        );
+        self.add_node(node, index);
+    }
+
     pub fn add_sticky_frame(
         &mut self,
         index: ClipScrollNodeIndex,
@@ -381,7 +446,12 @@ impl ClipScrollTree {
         sticky_frame_info: StickyFrameInfo,
         pipeline_id: PipelineId,
     ) {
-        let node = ClipScrollNode::new_sticky_frame(parent_index, sticky_frame_info, pipeline_id);
+        let node = ClipScrollNode::new_sticky_frame(
+            parent_index,
+            sticky_frame_info,
+            pipeline_id,
+            self.next_transform_index(),
+        );
         self.add_node(node, index);
     }
 
@@ -436,6 +506,26 @@ impl ClipScrollTree {
     ) {
         let node = &self.nodes[index.0];
         match node.node_type {
+            NodeType::Spatial { ref kind, .. } => {
+                match *kind {
+                    SpatialNodeKind::StickyFrame(ref sticky_frame_info) => {
+                        pt.new_level(format!("StickyFrame"));
+                        pt.add_item(format!("index: {:?}", index));
+                        pt.add_item(format!("sticky info: {:?}", sticky_frame_info));
+                    }
+                    SpatialNodeKind::ScrollFrame(scrolling_info) => {
+                        pt.new_level(format!("ScrollFrame"));
+                        pt.add_item(format!("index: {:?}", index));
+                        pt.add_item(format!("viewport: {:?}", scrolling_info.viewport_rect));
+                        pt.add_item(format!("scrollable_size: {:?}", scrolling_info.scrollable_size));
+                        pt.add_item(format!("scroll offset: {:?}", scrolling_info.offset));
+                    }
+                    SpatialNodeKind::ReferenceFrame(ref info) => {
+                        pt.new_level(format!("ReferenceFrame {:?}", info.resolved_transform));
+                        pt.add_item(format!("index: {:?}", index));
+                    }
+                }
+            }
             NodeType::Clip { ref handle, .. } => {
                 pt.new_level("Clip".to_owned());
 
@@ -447,22 +537,6 @@ impl ClipScrollTree {
                 }
                 pt.end_level();
             }
-            NodeType::ReferenceFrame(ref info) => {
-                pt.new_level(format!("ReferenceFrame {:?}", info.resolved_transform));
-                pt.add_item(format!("index: {:?}", index));
-            }
-            NodeType::ScrollFrame(scrolling_info) => {
-                pt.new_level(format!("ScrollFrame"));
-                pt.add_item(format!("index: {:?}", index));
-                pt.add_item(format!("viewport: {:?}", scrolling_info.viewport_rect));
-                pt.add_item(format!("scrollable_size: {:?}", scrolling_info.scrollable_size));
-                pt.add_item(format!("scroll offset: {:?}", scrolling_info.offset));
-            }
-            NodeType::StickyFrame(ref sticky_frame_info) => {
-                pt.new_level(format!("StickyFrame"));
-                pt.add_item(format!("index: {:?}", index));
-                pt.add_item(format!("sticky info: {:?}", sticky_frame_info));
-            }
             NodeType::Empty => unreachable!("Empty node remaining in ClipScrollTree."),
         }
 

gfx/webrender/src/device/gl.rs

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use super::shader_source;
+use super::super::shader_source;
 use api::{ColorF, ImageFormat};
 use api::{DeviceIntPoint, DeviceIntRect, DeviceUintRect, DeviceUintSize};
 use api::TextureTarget;
@@ -2234,6 +2234,11 @@ impl Device {
                 external: gl::RGBA,
                 pixel_type: gl::FLOAT,
             },
+            ImageFormat::RGBAI32 => FormatDesc {
+                internal: gl::RGBA32I as _,
+                external: gl::RGBA_INTEGER,
+                pixel_type: gl::INT,
+            },
             ImageFormat::RG8 => FormatDesc {
                 internal: gl::RG8 as _,
                 external: gl::RG,
@@ -2360,6 +2365,7 @@ impl<'a> UploadTarget<'a> {
             ImageFormat::BGRA8 => (self.bgra_format, 4, gl::UNSIGNED_BYTE),
             ImageFormat::RG8 => (gl::RG, 2, gl::UNSIGNED_BYTE),
             ImageFormat::RGBAF32 => (gl::RGBA, 16, gl::FLOAT),
+            ImageFormat::RGBAI32 => (gl::RGBA_INTEGER, 16, gl::INT),
         };
 
         let row_length = match chunk.stride {

gfx/webrender/src/device/mod.rs

@@ -0,0 +1,7 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+mod gl;
+
+pub use self::gl::*;

gfx/webrender/src/display_list_flattener.rs

@@ -14,10 +14,10 @@ use api::{PropertyBinding, ReferenceFrame, RepeatMode, ScrollFrameDisplayItem, S
 use api::{Shadow, SpecificDisplayItem, StackingContext, StickyFrameDisplayItem, TexelRect};
 use api::{TransformStyle, YuvColorSpace, YuvData};
 use clip::{ClipRegion, ClipSource, ClipSources, ClipStore};
-use clip_scroll_node::{ClipScrollNode, NodeType, StickyFrameInfo};
+use clip_scroll_node::{NodeType, SpatialNodeKind, StickyFrameInfo};
 use clip_scroll_tree::{ClipChainIndex, ClipScrollNodeIndex, ClipScrollTree};
-use euclid::{SideOffsets2D, vec2};
-use frame_builder::{FrameBuilder, FrameBuilderConfig};
+use euclid::vec2;
+use frame_builder::{ChasePrimitive, FrameBuilder, FrameBuilderConfig};
 use glyph_rasterizer::FontInstance;
 use gpu_cache::GpuCacheHandle;
 use gpu_types::BrushFlags;
@@ -628,8 +628,7 @@ impl<'a> DisplayListFlattener<'a> {
                 );
             }
             SpecificDisplayItem::Gradient(ref info) => {
-                self.add_gradient(
-                    clip_and_scroll,
+                let brush_kind = self.create_brush_kind_for_gradient(
                     &prim_info,
                     info.gradient.start_point,
                     info.gradient.end_point,
@@ -638,10 +637,11 @@ impl<'a> DisplayListFlattener<'a> {
                     info.tile_size,
                     info.tile_spacing,
                 );
+                let prim = PrimitiveContainer::Brush(BrushPrimitive::new(brush_kind, None));
+                self.add_primitive(clip_and_scroll, &prim_info, Vec::new(), prim);
             }
             SpecificDisplayItem::RadialGradient(ref info) => {
-                self.add_radial_gradient(
-                    clip_and_scroll,
+                let brush_kind = self.create_brush_kind_for_radial_gradient(
                     &prim_info,
                     info.gradient.center,
                     info.gradient.start_offset * info.gradient.radius.width,
@@ -652,6 +652,8 @@ impl<'a> DisplayListFlattener<'a> {
                     info.tile_size,
                     info.tile_spacing,
                 );
+                let prim = PrimitiveContainer::Brush(BrushPrimitive::new(brush_kind, None));
+                self.add_primitive(clip_and_scroll, &prim_info, Vec::new(), prim);
             }
             SpecificDisplayItem::BoxShadow(ref box_shadow_info) => {
                 let bounds = box_shadow_info
@@ -875,6 +877,10 @@ impl<'a> DisplayListFlattener<'a> {
 
         if container.is_visible() {
             let prim_index = self.create_primitive(info, clip_sources, container);
+            if cfg!(debug_assertions) && ChasePrimitive::LocalRect(info.rect) == self.config.chase_primitive {
+                println!("Chasing {:?}", prim_index);
+                self.prim_store.chase_id = Some(prim_index);
+            }
             self.add_primitive_to_hit_testing_list(info, clip_and_scroll);
             self.add_primitive_to_draw_list(prim_index, clip_and_scroll);
         }
@@ -1197,14 +1203,15 @@ impl<'a> DisplayListFlattener<'a> {
         origin_in_parent_reference_frame: LayoutVector2D,
     ) -> ClipScrollNodeIndex {
         let index = self.id_to_index_mapper.get_node_index(reference_frame_id);
-        let node = ClipScrollNode::new_reference_frame(
-            parent_id.map(|id| self.id_to_index_mapper.get_node_index(id)),
+        let parent_index = parent_id.map(|id| self.id_to_index_mapper.get_node_index(id));
+        self.clip_scroll_tree.add_reference_frame(
+            index,
+            parent_index,
             source_transform,
             source_perspective,
             origin_in_parent_reference_frame,
             pipeline_id,
         );
-        self.clip_scroll_tree.add_node(node, index);
         self.reference_frame_stack.push((reference_frame_id, index));
 
         match parent_id {
@@ -1227,7 +1234,7 @@ impl<'a> DisplayListFlattener<'a> {
         let viewport_offset = (inner_rect.origin.to_vector().to_f32() / device_pixel_scale).round();
         let root_id = self.clip_scroll_tree.root_reference_frame_index();
         let root_node = &mut self.clip_scroll_tree.nodes[root_id.0];
-        if let NodeType::ReferenceFrame(ref mut info) = root_node.node_type {
+        if let NodeType::Spatial { kind: SpatialNodeKind::ReferenceFrame(ref mut info), .. } = root_node.node_type {
             info.resolved_transform =
                 LayoutVector2D::new(viewport_offset.x, viewport_offset.y).into();
         }
@@ -1290,16 +1297,15 @@ impl<'a> DisplayListFlattener<'a> {
         scroll_sensitivity: ScrollSensitivity,
     ) -> ClipScrollNodeIndex {
         let node_index = self.id_to_index_mapper.get_node_index(new_node_id);
-        let node = ClipScrollNode::new_scroll_frame(
-            pipeline_id,
+        self.clip_scroll_tree.add_scroll_frame(
+            node_index,
             self.id_to_index_mapper.get_node_index(parent_id),
             external_id,
+            pipeline_id,
             frame_rect,
             content_size,
             scroll_sensitivity,
         );
-
-        self.clip_scroll_tree.add_node(node, node_index);
         self.id_to_index_mapper.map_to_parent_clip_chain(new_node_id, &parent_id);
         node_index
     }
@@ -1492,51 +1498,6 @@ impl<'a> DisplayListFlattener<'a> {
         gradient_stops: ItemRange<GradientStop>,
     ) {
         let rect = info.rect;
-        let create_segments = |outset: SideOffsets2D<f32>| {
-            // Calculate the modified rect as specific by border-image-outset
-            let origin = LayoutPoint::new(rect.origin.x - outset.left, rect.origin.y - outset.top);
-            let size = LayoutSize::new(
-                rect.size.width + outset.left + outset.right,
-                rect.size.height + outset.top + outset.bottom,
-            );
-            let rect = LayoutRect::new(origin, size);
-
-            let tl_outer = LayoutPoint::new(rect.origin.x, rect.origin.y);
-            let tl_inner = tl_outer + vec2(border_item.widths.left, border_item.widths.top);
-
-            let tr_outer = LayoutPoint::new(rect.origin.x + rect.size.width, rect.origin.y);
-            let tr_inner = tr_outer + vec2(-border_item.widths.right, border_item.widths.top);
-
-            let bl_outer = LayoutPoint::new(rect.origin.x, rect.origin.y + rect.size.height);
-            let bl_inner = bl_outer + vec2(border_item.widths.left, -border_item.widths.bottom);
-
-            let br_outer = LayoutPoint::new(
-                rect.origin.x + rect.size.width,
-                rect.origin.y + rect.size.height,
-            );
-            let br_inner = br_outer - vec2(border_item.widths.right, border_item.widths.bottom);
-
-            // Build the list of gradient segments
-            vec![
-                // Top left
-                LayoutRect::from_floats(tl_outer.x, tl_outer.y, tl_inner.x, tl_inner.y),
-                // Top right
-                LayoutRect::from_floats(tr_inner.x, tr_outer.y, tr_outer.x, tr_inner.y),
-                // Bottom right
-                LayoutRect::from_floats(br_inner.x, br_inner.y, br_outer.x, br_outer.y),
-                // Bottom left
-                LayoutRect::from_floats(bl_outer.x, bl_inner.y, bl_inner.x, bl_outer.y),
-                // Top
-                LayoutRect::from_floats(tl_inner.x, tl_outer.y, tr_inner.x, tl_inner.y),
-                // Bottom
-                LayoutRect::from_floats(bl_inner.x, bl_inner.y, br_inner.x, bl_outer.y),
-                // Left
-                LayoutRect::from_floats(tl_outer.x, tl_inner.y, tl_inner.x, bl_inner.y),
-                // Right
-                LayoutRect::from_floats(tr_inner.x, tr_inner.y, br_outer.x, br_inner.y),
-            ]
-        };
-
         match border_item.details {
             BorderDetails::NinePatch(ref border) => {
                 // Calculate the modified rect as specific by border-image-outset
@@ -1701,70 +1662,55 @@ impl<'a> DisplayListFlattener<'a> {
                     clip_mask_kind: BrushClipMaskKind::Unknown,
                 };
 
-                let prim = PrimitiveContainer::Brush(match border.source {
+                let brush_kind = match border.source {
                     NinePatchBorderSource::Image(image_key) => {
-                        let source = BorderSource::Image(ImageRequest {
-                            key: image_key,
-                            rendering: ImageRendering::Auto,
-                            tile: None,
-                        });
-
-                        BrushPrimitive::new(
-                            BrushKind::Border {
-                                source
-                            },
-                            Some(descriptor),
+                        BrushKind::Border {
+                            source: BorderSource::Image(ImageRequest {
+                                key: image_key,
+                                rendering: ImageRendering::Auto,
+                                tile: None,
+                            })
+                        }
+                    }
+                    NinePatchBorderSource::Gradient(gradient) => {
+                        self.create_brush_kind_for_gradient(
+                            &info,
+                            gradient.start_point,
+                            gradient.end_point,
+                            gradient_stops,
+                            gradient.extend_mode,
+                            LayoutSize::new(border.height as f32, border.width as f32),
+                            LayoutSize::zero(),
                         )
                     }
-                });
+                    NinePatchBorderSource::RadialGradient(gradient) => {
+                        self.create_brush_kind_for_radial_gradient(
+                            &info,
+                            gradient.center,
+                            gradient.start_offset * gradient.radius.width,
+                            gradient.end_offset * gradient.radius.width,
+                            gradient.radius.width / gradient.radius.height,
+                            gradient_stops,
+                            gradient.extend_mode,
+                            LayoutSize::new(border.height as f32, border.width as f32),
+                            LayoutSize::zero(),
+                        )
+                    }
+                };
 
+                let prim = PrimitiveContainer::Brush(
+                    BrushPrimitive::new(brush_kind, Some(descriptor))
+                );
                 self.add_primitive(clip_and_scroll, info, Vec::new(), prim);
             }
             BorderDetails::Normal(ref border) => {
                 self.add_normal_border(info, border, &border_item.widths, clip_and_scroll);
             }
-            BorderDetails::Gradient(ref border) => for segment in create_segments(border.outset) {
-                let segment_rel = segment.origin - rect.origin;
-                let mut info = info.clone();
-                info.rect = segment;
-
-                self.add_gradient(
-                    clip_and_scroll,
-                    &info,
-                    border.gradient.start_point - segment_rel,
-                    border.gradient.end_point - segment_rel,
-                    gradient_stops,
-                    border.gradient.extend_mode,
-                    segment.size,
-                    LayoutSize::zero(),
-                );
-            },
-            BorderDetails::RadialGradient(ref border) => {
-                for segment in create_segments(border.outset) {
-                    let segment_rel = segment.origin - rect.origin;
-                    let mut info = info.clone();
-                    info.rect = segment;
-
-                    self.add_radial_gradient(
-                        clip_and_scroll,
-                        &info,
-                        border.gradient.center - segment_rel,
-                        border.gradient.start_offset * border.gradient.radius.width,
-                        border.gradient.end_offset * border.gradient.radius.width,
-                        border.gradient.radius.width / border.gradient.radius.height,
-                        gradient_stops,
-                        border.gradient.extend_mode,
-                        segment.size,
-                        LayoutSize::zero(),
-                    );
-                }
-            }
         }
     }
 
-    pub fn add_gradient(
+    pub fn create_brush_kind_for_gradient(
         &mut self,
-        clip_and_scroll: ScrollNodeAndClipChain,
         info: &LayoutPrimitiveInfo,
         start_point: LayoutPoint,
         end_point: LayoutPoint,
@@ -1772,13 +1718,9 @@ impl<'a> DisplayListFlattener<'a> {
         extend_mode: ExtendMode,
         stretch_size: LayoutSize,
         mut tile_spacing: LayoutSize,
-    ) {
+    ) -> BrushKind {
         let mut prim_rect = info.rect;
         simplify_repeated_primitive(&stretch_size, &mut tile_spacing, &mut prim_rect);
-        let info = LayoutPrimitiveInfo {
-            rect: prim_rect,
-            .. *info
-        };
 
         // Try to ensure that if the gradient is specified in reverse, then so long as the stops
         // are also supplied in reverse that the rendered result will be equivalent. To do this,
@@ -1798,29 +1740,21 @@ impl<'a> DisplayListFlattener<'a> {
             (start_point, end_point)
         };
 
-        let prim = BrushPrimitive::new(
-            BrushKind::LinearGradient {
-                stops_range: stops,
-                extend_mode,
-                reverse_stops,
-                start_point: sp,
-                end_point: ep,
-                stops_handle: GpuCacheHandle::new(),
-                stretch_size,
-                tile_spacing,
-                visible_tiles: Vec::new(),
-            },
-            None,
-        );
-
-        let prim = PrimitiveContainer::Brush(prim);
-
-        self.add_primitive(clip_and_scroll, &info, Vec::new(), prim);
+        BrushKind::LinearGradient {
+            stops_range: stops,
+            extend_mode,
+            reverse_stops,
+            start_point: sp,
+            end_point: ep,
+            stops_handle: GpuCacheHandle::new(),
+            stretch_size,
+            tile_spacing,
+            visible_tiles: Vec::new(),
+        }
     }
 
-    pub fn add_radial_gradient(
+    pub fn create_brush_kind_for_radial_gradient(
         &mut self,
-        clip_and_scroll: ScrollNodeAndClipChain,
         info: &LayoutPrimitiveInfo,
         center: LayoutPoint,
         start_radius: f32,
@@ -1830,36 +1764,22 @@ impl<'a> DisplayListFlattener<'a> {
         extend_mode: ExtendMode,
         stretch_size: LayoutSize,
         mut tile_spacing: LayoutSize,
-    ) {
+    ) -> BrushKind {
         let mut prim_rect = info.rect;
         simplify_repeated_primitive(&stretch_size, &mut tile_spacing, &mut prim_rect);
-        let info = LayoutPrimitiveInfo {
-            rect: prim_rect,
-            .. *info
-        };
 
-        let prim = BrushPrimitive::new(
-            BrushKind::RadialGradient {
-                stops_range: stops,
-                extend_mode,
-                center,
-                start_radius,
-                end_radius,
-                ratio_xy,
-                stops_handle: GpuCacheHandle::new(),
-                stretch_size,
-                tile_spacing,
-                visible_tiles: Vec::new(),
-            },
-            None,
-        );
-
-        self.add_primitive(
-            clip_and_scroll,
-            &info,
-            Vec::new(),
-            PrimitiveContainer::Brush(prim),
-        );
+        BrushKind::RadialGradient {
+            stops_range: stops,
+            extend_mode,
+            center,
+            start_radius,
+            end_radius,
+            ratio_xy,
+            stops_handle: GpuCacheHandle::new(),
+            stretch_size,
+            tile_spacing,
+            visible_tiles: Vec::new(),
+        }
     }
 
     pub fn add_text(

gfx/webrender/src/frame_builder.rs

@@ -4,13 +4,13 @@
 
 use api::{BuiltDisplayList, ColorF, DeviceIntPoint, DeviceIntRect, DevicePixelScale};
 use api::{DeviceUintPoint, DeviceUintRect, DeviceUintSize, DocumentLayer, FontRenderMode};
-use api::{LayoutRect, LayoutSize, PipelineId, WorldPoint};
+use api::{LayoutPoint, LayoutRect, LayoutSize, PipelineId, WorldPoint};
 use clip::{ClipChain, ClipStore};
 use clip_scroll_node::{ClipScrollNode};
 use clip_scroll_tree::{ClipScrollNodeIndex, ClipScrollTree};
 use display_list_flattener::{DisplayListFlattener};
 use gpu_cache::GpuCache;
-use gpu_types::{ClipChainRectIndex, ClipScrollNodeData, UvRectKind};
+use gpu_types::{PrimitiveHeaders, TransformData, UvRectKind};
 use hit_test::{HitTester, HitTestingRun};
 use internal_types::{FastHashMap};
 use picture::PictureSurface;
@@ -24,7 +24,22 @@ use std::{mem, f32};
 use std::sync::Arc;
 use tiling::{Frame, RenderPass, RenderPassKind, RenderTargetContext};
 use tiling::{ScrollbarPrimitive, SpecialRenderPasses};
-use util::{self, MaxRect, WorldToLayoutFastTransform};
+use util::{self, WorldToLayoutFastTransform};
+
+
+#[derive(Clone, Copy, Debug, PartialEq)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub enum ChasePrimitive {
+    Nothing,
+    LocalRect(LayoutRect),
+}
+
+impl Default for ChasePrimitive {
+    fn default() -> Self {
+        ChasePrimitive::Nothing
+    }
+}
 
 #[derive(Clone, Copy)]
 #[cfg_attr(feature = "capture", derive(Serialize))]
@@ -34,6 +49,7 @@ pub struct FrameBuilderConfig {
     pub default_font_render_mode: FontRenderMode,
     pub dual_source_blending_is_supported: bool,
     pub dual_source_blending_is_enabled: bool,
+    pub chase_primitive: ChasePrimitive,
 }
 
 /// A builder structure for `tiling::Frame`
@@ -56,14 +72,14 @@ pub struct FrameBuildingContext<'a> {
     pub pipelines: &'a FastHashMap<PipelineId, Arc<ScenePipeline>>,
     pub screen_rect: DeviceIntRect,
     pub clip_scroll_tree: &'a ClipScrollTree,
-    pub node_data: &'a [ClipScrollNodeData],
+    pub transforms: &'a [TransformData],
+    pub max_local_clip: LayoutRect,
 }
 
 pub struct FrameBuildingState<'a> {
     pub render_tasks: &'a mut RenderTaskTree,
     pub profile_counters: &'a mut FrameProfileCounters,
     pub clip_store: &'a mut ClipStore,
-    pub local_clip_rects: &'a mut Vec<LayoutRect>,
     pub resource_cache: &'a mut ResourceCache,
     pub gpu_cache: &'a mut GpuCache,
     pub special_render_passes: &'a mut SpecialRenderPasses,
@@ -99,19 +115,19 @@ impl PictureState {
 pub struct PrimitiveRunContext<'a> {
     pub clip_chain: &'a ClipChain,
     pub scroll_node: &'a ClipScrollNode,
-    pub clip_chain_rect_index: ClipChainRectIndex,
+    pub local_clip_rect: LayoutRect,
 }
 
 impl<'a> PrimitiveRunContext<'a> {
     pub fn new(
         clip_chain: &'a ClipChain,
         scroll_node: &'a ClipScrollNode,
-        clip_chain_rect_index: ClipChainRectIndex,
+        local_clip_rect: LayoutRect,
     ) -> Self {
         PrimitiveRunContext {
             clip_chain,
             scroll_node,
-            clip_chain_rect_index,
+            local_clip_rect,
         }
     }
 }
@@ -132,6 +148,7 @@ impl FrameBuilder {
                 default_font_render_mode: FontRenderMode::Mono,
                 dual_source_blending_is_enabled: true,
                 dual_source_blending_is_supported: false,
+                chase_primitive: ChasePrimitive::Nothing,
             },
         }
     }
@@ -169,8 +186,7 @@ impl FrameBuilder {
         profile_counters: &mut FrameProfileCounters,
         device_pixel_scale: DevicePixelScale,
         scene_properties: &SceneProperties,
-        local_clip_rects: &mut Vec<LayoutRect>,
-        node_data: &[ClipScrollNodeData],
+        transforms: &[TransformData],
     ) -> Option<RenderTaskId> {
         profile_scope!("cull");
 
@@ -187,6 +203,8 @@ impl FrameBuilder {
             .expect("No display list?")
             .display_list;
 
+        const MAX_CLIP_COORD: f32 = 1.0e9;
+
         let frame_context = FrameBuildingContext {
             scene_id: self.scene_id,
             device_pixel_scale,
@@ -194,14 +212,17 @@ impl FrameBuilder {
             pipelines,
             screen_rect: self.screen_rect.to_i32(),
             clip_scroll_tree,
-            node_data,
+            transforms,
+            max_local_clip: LayoutRect::new(
+                LayoutPoint::new(-MAX_CLIP_COORD, -MAX_CLIP_COORD),
+                LayoutSize::new(2.0 * MAX_CLIP_COORD, 2.0 * MAX_CLIP_COORD),
+            ),
         };
 
         let mut frame_state = FrameBuildingState {
             render_tasks,
             profile_counters,
             clip_store: &mut self.clip_store,
-            local_clip_rects,
             resource_cache,
             gpu_cache,
             special_render_passes,
@@ -301,20 +322,13 @@ impl FrameBuilder {
         resource_cache.begin_frame(frame_id);
         gpu_cache.begin_frame();
 
-        let mut node_data = Vec::with_capacity(clip_scroll_tree.nodes.len());
-        let total_prim_runs =
-            self.prim_store.pictures.iter().fold(1, |count, pic| count + pic.runs.len());
-        let mut clip_chain_local_clip_rects = Vec::with_capacity(total_prim_runs);
-        clip_chain_local_clip_rects.push(LayoutRect::max_rect());
-
-        clip_scroll_tree.update_tree(
+        let transform_palette = clip_scroll_tree.update_tree(
             &self.screen_rect.to_i32(),
             device_pixel_scale,
             &mut self.clip_store,
             resource_cache,
             gpu_cache,
             pan,
-            &mut node_data,
             scene_properties,
         );
 
@@ -335,8 +349,7 @@ impl FrameBuilder {
             &mut profile_counters,
             device_pixel_scale,
             scene_properties,
-            &mut clip_chain_local_clip_rects,
-            &node_data,
+            &transform_palette.transforms,
         );
 
         resource_cache.block_until_all_resources_added(gpu_cache,
@@ -369,6 +382,7 @@ impl FrameBuilder {
 
         let mut deferred_resolves = vec![];
         let mut has_texture_cache_tasks = false;
+        let mut prim_headers = PrimitiveHeaders::new();
         let use_dual_source_blending = self.config.dual_source_blending_is_enabled &&
                                        self.config.dual_source_blending_is_supported;
 
@@ -379,7 +393,7 @@ impl FrameBuilder {
                 resource_cache,
                 clip_scroll_tree,
                 use_dual_source_blending,
-                node_data: &node_data,
+                transforms: &transform_palette,
             };
 
             pass.build(
@@ -388,6 +402,7 @@ impl FrameBuilder {
                 &mut render_tasks,
                 &mut deferred_resolves,
                 &self.clip_store,
+                &mut prim_headers,
             );
 
             if let RenderPassKind::OffScreen { ref texture_cache, .. } = pass.kind {
@@ -409,13 +424,13 @@ impl FrameBuilder {
             layer,
             profile_counters,
             passes,
-            node_data,
-            clip_chain_local_clip_rects,
+            transform_palette: transform_palette.transforms,
             render_tasks,
             deferred_resolves,
             gpu_cache_frame_id,
             has_been_rendered: false,
             has_texture_cache_tasks,
+            prim_headers,
         }
     }
 

gfx/webrender/src/gpu_types.rs

@@ -2,29 +2,25 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use api::{DevicePoint, DeviceSize, DeviceRect, LayoutToWorldTransform};
+use api::{DevicePoint, DeviceSize, DeviceRect, LayoutRect, LayoutToWorldTransform};
 use api::{PremultipliedColorF, WorldToLayoutTransform};
+use clip_scroll_tree::TransformIndex;
 use gpu_cache::{GpuCacheAddress, GpuDataRequest};
-use prim_store::{VECS_PER_SEGMENT, EdgeAaSegmentMask};
+use prim_store::{EdgeAaSegmentMask};
 use render_task::RenderTaskAddress;
-use renderer::MAX_VERTEX_TEXTURE_WIDTH;
+use util::{MatrixHelpers, TransformedRectKind};
 
 // Contains type that must exactly match the same structures declared in GLSL.
 
-const INT_BITS: usize = 31; //TODO: convert to unsigned
-const CLIP_CHAIN_RECT_BITS: usize = 22;
-const SEGMENT_BITS: usize = INT_BITS - CLIP_CHAIN_RECT_BITS;
-// The guard ensures (at compile time) that the designated number of bits cover
-// the maximum supported segment count for the texture width.
-const _SEGMENT_GUARD: usize = (1 << SEGMENT_BITS) * VECS_PER_SEGMENT - MAX_VERTEX_TEXTURE_WIDTH;
-const EDGE_FLAG_BITS: usize = 4;
-const BRUSH_FLAG_BITS: usize = 4;
-const CLIP_SCROLL_INDEX_BITS: usize = INT_BITS - EDGE_FLAG_BITS - BRUSH_FLAG_BITS;
-
 #[derive(Copy, Clone, Debug)]
 #[repr(C)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
 pub struct ZBufferId(i32);
 
+#[derive(Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
 pub struct ZBufferIdGenerator {
     next: i32,
 }
@@ -119,7 +115,7 @@ pub struct BorderInstance {
 #[repr(C)]
 pub struct ClipMaskInstance {
     pub render_task_address: RenderTaskAddress,
-    pub scroll_node_data_index: ClipScrollNodeIndex,
+    pub transform_id: TransformPaletteId,
     pub segment: i32,
     pub clip_data_address: GpuCacheAddress,
     pub resource_address: GpuCacheAddress,
@@ -135,50 +131,124 @@ pub struct ClipMaskBorderCornerDotDash {
     pub dot_dash_data: [f32; 8],
 }
 
-// 32 bytes per instance should be enough for anyone!
+// 16 bytes per instance should be enough for anyone!
 #[derive(Debug, Clone)]
 #[cfg_attr(feature = "capture", derive(Serialize))]
 #[cfg_attr(feature = "replay", derive(Deserialize))]
 pub struct PrimitiveInstance {
-    data: [i32; 8],
+    data: [i32; 4],
+}
+
+#[derive(Debug, Copy, Clone)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct PrimitiveHeaderIndex(pub i32);
+
+#[derive(Debug)]
+#[repr(C)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct PrimitiveHeaders {
+    // The integer-type headers for a primitive.
+    pub headers_int: Vec<PrimitiveHeaderI>,
+    // The float-type headers for a primitive.
+    pub headers_float: Vec<PrimitiveHeaderF>,
+    // Used to generated a unique z-buffer value per primitive.
+    pub z_generator: ZBufferIdGenerator,
+}
+
+impl PrimitiveHeaders {
+    pub fn new() -> PrimitiveHeaders {
+        PrimitiveHeaders {
+            headers_int: Vec::new(),
+            headers_float: Vec::new(),
+            z_generator: ZBufferIdGenerator::new(),
+        }
+    }
+
+    // Add a new primitive header.
+    pub fn push(
+        &mut self,
+        prim_header: &PrimitiveHeader,
+        user_data: [i32; 3],
+    ) -> PrimitiveHeaderIndex {
+        debug_assert_eq!(self.headers_int.len(), self.headers_float.len());
+        let id = self.headers_float.len();
+
+        self.headers_float.push(PrimitiveHeaderF {
+            local_rect: prim_header.local_rect,
+            local_clip_rect: prim_header.local_clip_rect,
+        });
+
+        self.headers_int.push(PrimitiveHeaderI {
+            z: self.z_generator.next(),
+            task_address: prim_header.task_address,
+            specific_prim_address: prim_header.specific_prim_address.as_int(),
+            clip_task_address: prim_header.clip_task_address,
+            transform_id: prim_header.transform_id,
+            user_data,
+        });
+
+        PrimitiveHeaderIndex(id as i32)
+    }
+}
+
+// This is a convenience type used to make it easier to pass
+// the common parts around during batching.
+pub struct PrimitiveHeader {
+    pub local_rect: LayoutRect,
+    pub local_clip_rect: LayoutRect,
+    pub task_address: RenderTaskAddress,
+    pub specific_prim_address: GpuCacheAddress,
+    pub clip_task_address: RenderTaskAddress,
+    pub transform_id: TransformPaletteId,
+}
+
+// f32 parts of a primitive header
+#[derive(Debug)]
+#[repr(C)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct PrimitiveHeaderF {
+    pub local_rect: LayoutRect,
+    pub local_clip_rect: LayoutRect,
+}
+
+// i32 parts of a primitive header
+// TODO(gw): Compress parts of these down to u16
+#[derive(Debug)]
+#[repr(C)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct PrimitiveHeaderI {
+    pub z: ZBufferId,
+    pub task_address: RenderTaskAddress,
+    pub specific_prim_address: i32,
+    pub clip_task_address: RenderTaskAddress,
+    pub transform_id: TransformPaletteId,
+    pub user_data: [i32; 3],
 }
 
 pub struct GlyphInstance {
-    pub specific_prim_address: GpuCacheAddress,
-    pub task_address: RenderTaskAddress,
-    pub clip_task_address: RenderTaskAddress,
-    pub clip_chain_rect_index: ClipChainRectIndex,
-    pub scroll_id: ClipScrollNodeIndex,
-    pub z: ZBufferId,
+    pub prim_header_index: PrimitiveHeaderIndex,
 }
 
 impl GlyphInstance {
     pub fn new(
-        specific_prim_address: GpuCacheAddress,
-        task_address: RenderTaskAddress,
-        clip_task_address: RenderTaskAddress,
-        clip_chain_rect_index: ClipChainRectIndex,
-        scroll_id: ClipScrollNodeIndex,
-        z: ZBufferId,
+        prim_header_index: PrimitiveHeaderIndex,
     ) -> Self {
         GlyphInstance {
-            specific_prim_address,
-            task_address,
-            clip_task_address,
-            clip_chain_rect_index,
-            scroll_id,
-            z,
+            prim_header_index,
         }
     }
 
+    // TODO(gw): Some of these fields can be moved to the primitive
+    //           header since they are constant, and some can be
+    //           compressed to a smaller size.
     pub fn build(&self, data0: i32, data1: i32, data2: i32) -> PrimitiveInstance {
         PrimitiveInstance {
             data: [
-                self.specific_prim_address.as_int(),
-                self.task_address.0 as i32 | (self.clip_task_address.0 as i32) << 16,
-                self.clip_chain_rect_index.0 as i32,
-                self.scroll_id.0 as i32,
-                self.z.0,
+                self.prim_header_index.0 as i32,
                 data0,
                 data1,
                 data2,
@@ -218,10 +288,6 @@ impl From<SplitCompositeInstance> for PrimitiveInstance {
                 instance.src_task_address.0 as i32,
                 instance.polygons_address.as_int(),
                 instance.z.0,
-                0,
-                0,
-                0,
-                0,
             ],
         }
     }
@@ -243,80 +309,141 @@ bitflags! {
     }
 }
 
-// TODO(gw): While we are converting things over, we
-//           need to have the instance be the same
-//           size as an old PrimitiveInstance. In the
-//           future, we can compress this vertex
-//           format a lot - e.g. z, render task
-//           addresses etc can reasonably become
-//           a u16 type.
+// TODO(gw): Some of these fields can be moved to the primitive
+//           header since they are constant, and some can be
+//           compressed to a smaller size.
 #[repr(C)]
 pub struct BrushInstance {
-    pub picture_address: RenderTaskAddress,
-    pub prim_address: GpuCacheAddress,
-    pub clip_chain_rect_index: ClipChainRectIndex,
-    pub scroll_id: ClipScrollNodeIndex,
+    pub prim_header_index: PrimitiveHeaderIndex,
     pub clip_task_address: RenderTaskAddress,
-    pub z: ZBufferId,
     pub segment_index: i32,
     pub edge_flags: EdgeAaSegmentMask,
     pub brush_flags: BrushFlags,
-    pub user_data: [i32; 3],
 }
 
 impl From<BrushInstance> for PrimitiveInstance {
     fn from(instance: BrushInstance) -> Self {
-        debug_assert_eq!(0, instance.clip_chain_rect_index.0 >> CLIP_CHAIN_RECT_BITS);
-        debug_assert_eq!(0, instance.scroll_id.0 >> CLIP_SCROLL_INDEX_BITS);
-        debug_assert_eq!(0, instance.segment_index >> SEGMENT_BITS);
         PrimitiveInstance {
             data: [
-                instance.picture_address.0 as i32 | (instance.clip_task_address.0 as i32) << 16,
-                instance.prim_address.as_int(),
-                instance.clip_chain_rect_index.0 as i32 | (instance.segment_index << CLIP_CHAIN_RECT_BITS),
-                instance.z.0,
-                instance.scroll_id.0 as i32 |
-                    ((instance.edge_flags.bits() as i32) << CLIP_SCROLL_INDEX_BITS) |
-                    ((instance.brush_flags.bits() as i32) << (CLIP_SCROLL_INDEX_BITS + EDGE_FLAG_BITS)),
-                instance.user_data[0],
-                instance.user_data[1],
-                instance.user_data[2],
+                instance.prim_header_index.0,
+                instance.clip_task_address.0 as i32,
+                instance.segment_index |
+                ((instance.edge_flags.bits() as i32) << 16) |
+                ((instance.brush_flags.bits() as i32) << 24),
+                0,
             ]
         }
     }
 }
 
+// Represents the information about a transform palette
+// entry that is passed to shaders. It includes an index
+// into the transform palette, and a set of flags. The
+// only flag currently used determines whether the
+// transform is axis-aligned (and this should have
+// pixel snapping applied).
 #[derive(Copy, Debug, Clone, PartialEq)]
 #[cfg_attr(feature = "capture", derive(Serialize))]
 #[cfg_attr(feature = "replay", derive(Deserialize))]
 #[repr(C)]
-pub struct ClipScrollNodeIndex(pub u32);
+pub struct TransformPaletteId(pub u32);
 
-#[derive(Debug)]
-#[cfg_attr(feature = "capture", derive(Serialize))]
-#[cfg_attr(feature = "replay", derive(Deserialize))]
-#[repr(C)]
-pub struct ClipScrollNodeData {
-    pub transform: LayoutToWorldTransform,
-    pub inv_transform: WorldToLayoutTransform,
-    pub transform_kind: f32,
-    pub padding: [f32; 3],
-}
+impl TransformPaletteId {
+    // Get the palette ID for an identity transform.
+    pub fn identity() -> TransformPaletteId {
+        TransformPaletteId(0)
+    }
 
-impl ClipScrollNodeData {
-    pub fn invalid() -> Self {
-        ClipScrollNodeData {
-            transform: LayoutToWorldTransform::identity(),
-            inv_transform: WorldToLayoutTransform::identity(),
-            transform_kind: 0.0,
-            padding: [0.0; 3],
+    // Extract the transform kind from the id.
+    pub fn transform_kind(&self) -> TransformedRectKind {
+        if (self.0 >> 24) == 0 {
+            TransformedRectKind::AxisAligned
+        } else {
+            TransformedRectKind::Complex
         }
     }
 }
 
-#[derive(Copy, Debug, Clone, PartialEq)]
+// The GPU data payload for a transform palette entry.
+#[derive(Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
 #[repr(C)]
-pub struct ClipChainRectIndex(pub usize);
+pub struct TransformData {
+    pub transform: LayoutToWorldTransform,
+    pub inv_transform: WorldToLayoutTransform,
+}
+
+impl TransformData {
+    pub fn invalid() -> Self {
+        TransformData {
+            transform: LayoutToWorldTransform::identity(),
+            inv_transform: WorldToLayoutTransform::identity(),
+        }
+    }
+}
+
+// Extra data stored about each transform palette entry.
+pub struct TransformMetadata {
+    pub transform_kind: TransformedRectKind,
+}
+
+// Stores a contiguous list of TransformData structs, that
+// are ready for upload to the GPU.
+// TODO(gw): For now, this only stores the complete local
+//           to world transform for each spatial node. In
+//           the future, the transform palette will support
+//           specifying a coordinate system that the transform
+//           should be relative to.
+pub struct TransformPalette {
+    pub transforms: Vec<TransformData>,
+    metadata: Vec<TransformMetadata>,
+}
+
+impl TransformPalette {
+    pub fn new(spatial_node_count: usize) -> TransformPalette {
+        TransformPalette {
+            transforms: Vec::with_capacity(spatial_node_count),
+            metadata: Vec::with_capacity(spatial_node_count),
+        }
+    }
+
+    // Set the local -> world transform for a given spatial
+    // node in the transform palette.
+    pub fn set(
+        &mut self,
+        index: TransformIndex,
+        data: TransformData,
+    ) {
+        let index = index.0 as usize;
+
+        // Pad the vectors out if they are not long enough to
+        // account for this index. This can occur, for instance,
+        // when we stop recursing down the CST due to encountering
+        // a node with an invalid transform.
+        while index >= self.transforms.len() {
+            self.transforms.push(TransformData::invalid());
+            self.metadata.push(TransformMetadata {
+                transform_kind: TransformedRectKind::AxisAligned,
+            });
+        }
+
+        // Store the transform itself, along with metadata about it.
+        self.metadata[index] = TransformMetadata {
+            transform_kind: data.transform.transform_kind(),
+        };
+        self.transforms[index] = data;
+    }
+
+    // Get a transform palette id for the given spatial node.
+    // TODO(gw): In the future, it will be possible to specify
+    //           a coordinate system id here, to allow retrieving
+    //           transforms in the local space of a given spatial node.
+    pub fn get_id(&self, index: TransformIndex) -> TransformPaletteId {
+        let transform_kind = self.metadata[index.0 as usize].transform_kind as u32;
+        TransformPaletteId(index.0 | (transform_kind << 24))
+    }
+}
 
 // Texture cache resources can be either a simple rect, or define
 // a polygon within a rect by specifying a UV coordinate for each

gfx/webrender/src/lib.rs

@@ -182,6 +182,7 @@ pub extern crate webrender_api;
 #[doc(hidden)]
 pub use device::{build_shader_strings, ReadPixelsFormat, UploadMethod, VertexUsageHint};
 pub use device::{ProgramBinary, ProgramCache, ProgramCacheObserver, ProgramSources};
+pub use frame_builder::ChasePrimitive;
 pub use renderer::{AsyncPropertySampler, CpuProfile, DebugFlags, OutputImageHandler, RendererKind};
 pub use renderer::{ExternalImage, ExternalImageHandler, ExternalImageSource, GpuProfile};
 pub use renderer::{GraphicsApi, GraphicsApiInfo, PipelineInfo, Renderer, RendererOptions};

gfx/webrender/src/picture.rs

@@ -276,7 +276,7 @@ impl PicturePrimitive {
         self.can_draw_directly_to_parent_surface()
     }
 
-    pub fn prepare_for_render_inner(
+    pub fn prepare_for_render(
         &mut self,
         prim_index: PrimitiveIndex,
         prim_metadata: &mut PrimitiveMetadata,
@@ -489,16 +489,9 @@ impl PicturePrimitive {
                     //           that writes a brush primitive header.
 
                     // Basic brush primitive header is (see end of prepare_prim_for_render_inner in prim_store.rs)
-                    //  local_rect
-                    //  clip_rect
                     //  [brush specific data]
                     //  [segment_rect, segment data]
                     let shadow_rect = prim_metadata.local_rect.translate(&offset);
-                    let shadow_clip_rect = prim_metadata.local_clip_rect.translate(&offset);
-
-                    // local_rect, clip_rect
-                    request.push(shadow_rect);
-                    request.push(shadow_clip_rect);
 
                     // ImageBrush colors
                     request.push(color.premultiplied());
@@ -592,27 +585,6 @@ impl PicturePrimitive {
             }
         }
     }
-
-    pub fn prepare_for_render(
-        &mut self,
-        prim_index: PrimitiveIndex,
-        prim_metadata: &mut PrimitiveMetadata,
-        prim_run_context: &PrimitiveRunContext,
-        pic_state_for_children: PictureState,
-        pic_state: &mut PictureState,
-        frame_context: &FrameBuildingContext,
-        frame_state: &mut FrameBuildingState,
-    ) {
-        self.prepare_for_render_inner(
-            prim_index,
-            prim_metadata,
-            prim_run_context,
-            pic_state_for_children,
-            pic_state,
-            frame_context,
-            frame_state,
-        );
-    }
 }
 
 // Calculate a single screen-space UV for a picture.

gfx/webrender/src/prim_store.rs

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use api::{AlphaType, BorderRadius, BoxShadowClipMode, BuiltDisplayList, ClipMode, ColorF, ComplexClipRegion};
+use api::{AlphaType, BorderRadius, BoxShadowClipMode, BuiltDisplayList, ClipMode, ColorF};
 use api::{DeviceIntRect, DeviceIntSize, DevicePixelScale, Epoch, ExtendMode};
 use api::{FilterOp, GlyphInstance, GradientStop, ImageKey, ImageRendering, ItemRange, ItemTag, TileOffset};
 use api::{GlyphRasterSpace, LayoutPoint, LayoutRect, LayoutSize, LayoutToWorldTransform, LayoutVector2D};
@@ -20,7 +20,7 @@ use frame_builder::PrimitiveRunContext;
 use glyph_rasterizer::{FontInstance, FontTransform, GlyphKey, FONT_SIZE_LIMIT};
 use gpu_cache::{GpuBlockData, GpuCache, GpuCacheAddress, GpuCacheHandle, GpuDataRequest,
                 ToGpuBlocks};
-use gpu_types::{BrushFlags, ClipChainRectIndex};
+use gpu_types::BrushFlags;
 use image::{for_each_tile, for_each_repetition};
 use picture::{PictureCompositeMode, PictureId, PicturePrimitive};
 #[cfg(debug_assertions)]
@@ -50,7 +50,7 @@ impl ScrollNodeAndClipChain {
     pub fn new(
         scroll_node_id: ClipScrollNodeIndex,
         clip_chain_index: ClipChainIndex
-    ) -> ScrollNodeAndClipChain {
+    ) -> Self {
         ScrollNodeAndClipChain { scroll_node_id, clip_chain_index }
     }
 }
@@ -62,6 +62,17 @@ pub struct PrimitiveRun {
     pub clip_and_scroll: ScrollNodeAndClipChain,
 }
 
+impl PrimitiveRun {
+    pub fn is_chasing(&self, index: Option<PrimitiveIndex>) -> bool {
+        match index {
+            Some(id) if cfg!(debug_assertions) => {
+                self.base_prim_index <= id && id.0 < self.base_prim_index.0 + self.count
+            }
+            _ => false,
+        }
+    }
+}
+
 #[derive(Debug, Copy, Clone)]
 pub struct PrimitiveOpacity {
     pub is_opaque: bool,
@@ -174,7 +185,11 @@ pub struct PrimitiveMetadata {
     //           storing them here.
     pub local_rect: LayoutRect,
     pub local_clip_rect: LayoutRect,
-    pub clip_chain_rect_index: ClipChainRectIndex,
+
+    // The current combined local clip for this primitive, from
+    // the primitive local clip above and the current clip chain.
+    pub combined_local_clip_rect: LayoutRect,
+
     pub is_backface_visible: bool,
     pub screen_rect: Option<ScreenRect>,
 
@@ -234,11 +249,15 @@ pub struct VisibleImageTile {
     pub tile_offset: TileOffset,
     pub handle: GpuCacheHandle,
     pub edge_flags: EdgeAaSegmentMask,
+    pub local_rect: LayoutRect,
+    pub local_clip_rect: LayoutRect,
 }
 
 #[derive(Debug)]
 pub struct VisibleGradientTile {
     pub handle: GpuCacheHandle,
+    pub local_rect: LayoutRect,
+    pub local_clip_rect: LayoutRect,
 }
 
 #[derive(Debug)]
@@ -418,14 +437,14 @@ impl BrushPrimitive {
     pub fn new(
         kind: BrushKind,
         segment_desc: Option<BrushSegmentDescriptor>,
-    ) -> BrushPrimitive {
+    ) -> Self {
         BrushPrimitive {
             kind,
             segment_desc,
         }
     }
 
-    pub fn new_picture(pic_index: PictureIndex) -> BrushPrimitive {
+    pub fn new_picture(pic_index: PictureIndex) -> Self {
         BrushPrimitive {
             kind: BrushKind::Picture {
                 pic_index,
@@ -719,7 +738,6 @@ impl<'a> GradientGpuBlockBuilder<'a> {
                 self.fill_colors(cur_idx, GRADIENT_DATA_TABLE_END, &PremultipliedColorF::WHITE, &cur_color, &mut entries);
             }
 
-
             // Fill in the last entry with the last color stop
             self.fill_colors(
                 GRADIENT_DATA_LAST_STOP,
@@ -739,12 +757,12 @@ impl<'a> GradientGpuBlockBuilder<'a> {
 
 #[derive(Debug, Clone)]
 pub struct TextRunPrimitiveCpu {
-    pub font: FontInstance,
+    pub specified_font: FontInstance,
+    pub used_font: FontInstance,
     pub offset: LayoutVector2D,
     pub glyph_range: ItemRange<GlyphInstance>,
     pub glyph_keys: Vec<GlyphKey>,
     pub glyph_gpu_blocks: Vec<GpuBlockData>,
-    pub glyph_transform: (DevicePixelScale, FontTransform),
     pub shadow: bool,
     pub glyph_raster_space: GlyphRasterSpace,
 }
@@ -759,60 +777,97 @@ impl TextRunPrimitiveCpu {
         glyph_raster_space: GlyphRasterSpace,
     ) -> Self {
         TextRunPrimitiveCpu {
-            font,
+            specified_font: font.clone(),
+            used_font: font,
             offset,
             glyph_range,
             glyph_keys,
             glyph_gpu_blocks: Vec::new(),
-            glyph_transform: (DevicePixelScale::new(1.0), FontTransform::identity()),
             shadow,
             glyph_raster_space,
         }
     }
 
-    pub fn get_font(
-        &self,
+    pub fn update_font_instance(
+        &mut self,
         device_pixel_scale: DevicePixelScale,
-        transform: LayoutToWorldTransform,
-    ) -> FontInstance {
-        let mut font = self.font.clone();
-        font.size = font.size.scale_by(device_pixel_scale.0);
+        transform: &LayoutToWorldTransform,
+        allow_subpixel_aa: bool,
+    ) -> bool {
+        // Get the current font size in device pixels
+        let device_font_size = self.specified_font.size.scale_by(device_pixel_scale.0);
+
+        // Determine if rasterizing glyphs in local or screen space.
         // Only support transforms that can be coerced to simple 2D transforms.
-        if transform.has_perspective_component() ||
+        let transform_glyphs = if transform.has_perspective_component() ||
            !transform.has_2d_inverse() ||
            // Font sizes larger than the limit need to be scaled, thus can't use subpixels.
-           transform.exceeds_2d_scale(FONT_SIZE_LIMIT / font.size.to_f64_px()) ||
+           transform.exceeds_2d_scale(FONT_SIZE_LIMIT / device_font_size.to_f64_px()) ||
            // Otherwise, ensure the font is rasterized in screen-space.
            self.glyph_raster_space != GlyphRasterSpace::Screen {
-            font.disable_subpixel_aa();
-            font.disable_subpixel_position();
+            false
         } else {
+            true
+        };
+
+        // Get the font transform matrix (skew / scale) from the complete transform.
+        let font_transform = if transform_glyphs {
             // Quantize the transform to minimize thrashing of the glyph cache.
-            font.transform = FontTransform::from(&transform).quantize();
+            FontTransform::from(transform).quantize()
+        } else {
+            FontTransform::identity()
+        };
+
+        // If the transform or device size is different, then the caller of
+        // this method needs to know to rebuild the glyphs.
+        let cache_dirty =
+            self.used_font.transform != font_transform ||
+            self.used_font.size != device_font_size;
+
+        // Construct used font instance from the specified font instance
+        self.used_font = FontInstance {
+            transform: font_transform,
+            size: device_font_size,
+            ..self.specified_font.clone()
+        };
+
+        // If subpixel AA is disabled due to the backing surface the glyphs
+        // are being drawn onto, disable it (unless we are using the
+        // specifial subpixel mode that estimates background color).
+        if !allow_subpixel_aa && self.specified_font.bg_color.a == 0 {
+            self.used_font.disable_subpixel_aa();
         }
-        font
+
+        // If using local space glyphs, we don't want subpixel AA
+        // or positioning.
+        if !transform_glyphs {
+            self.used_font.disable_subpixel_aa();
+            self.used_font.disable_subpixel_position();
+        }
+
+        cache_dirty
     }
 
     fn prepare_for_render(
         &mut self,
         device_pixel_scale: DevicePixelScale,
-        transform: LayoutToWorldTransform,
+        transform: &LayoutToWorldTransform,
         allow_subpixel_aa: bool,
         display_list: &BuiltDisplayList,
         frame_building_state: &mut FrameBuildingState,
     ) {
-        if !allow_subpixel_aa && self.font.bg_color.a == 0 {
-            self.font.disable_subpixel_aa();
-        }
-
-        let font = self.get_font(device_pixel_scale, transform);
+        let cache_dirty = self.update_font_instance(
+            device_pixel_scale,
+            transform,
+            allow_subpixel_aa,
+        );
 
         // Cache the glyph positions, if not in the cache already.
         // TODO(gw): In the future, remove `glyph_instances`
         //           completely, and just reference the glyphs
         //           directly from the display list.
-        if self.glyph_keys.is_empty() || self.glyph_transform != (device_pixel_scale, font.transform) {
-            let subpx_dir = font.get_subpx_dir();
+        if self.glyph_keys.is_empty() || cache_dirty {
+            let subpx_dir = self.used_font.get_subpx_dir();
             let src_glyphs = display_list.get(self.glyph_range);
 
             // TODO(gw): If we support chunks() on AuxIter
@@ -820,7 +875,7 @@ impl TextRunPrimitiveCpu {
             //           be much simpler...
             let mut gpu_block = [0.0; 4];
             for (i, src) in src_glyphs.enumerate() {
-                let world_offset = font.transform.transform(&src.point);
+                let world_offset = self.used_font.transform.transform(&src.point);
                 let device_offset = device_pixel_scale.transform_point(&world_offset);
                 let key = GlyphKey::new(src.index, device_offset, subpx_dir);
                 self.glyph_keys.push(key);
@@ -842,12 +897,10 @@ impl TextRunPrimitiveCpu {
             if (self.glyph_keys.len() & 1) != 0 {
                 self.glyph_gpu_blocks.push(gpu_block.into());
             }
-
-            self.glyph_transform = (device_pixel_scale, font.transform);
         }
 
         frame_building_state.resource_cache
-                            .request_glyphs(font,
+                            .request_glyphs(self.used_font.clone(),
                                             &self.glyph_keys,
                                             frame_building_state.gpu_cache,
                                             frame_building_state.render_tasks,
@@ -855,9 +908,9 @@ impl TextRunPrimitiveCpu {
     }
 
     fn write_gpu_blocks(&self, request: &mut GpuDataRequest) {
-        request.push(ColorF::from(self.font.color).premultiplied());
+        request.push(ColorF::from(self.used_font.color).premultiplied());
         // this is the only case where we need to provide plain color to GPU
-        let bg_color = ColorF::from(self.font.bg_color);
+        let bg_color = ColorF::from(self.used_font.bg_color);
         request.push([bg_color.r, bg_color.g, bg_color.b, 1.0]);
         request.push([
             self.offset.x,
@@ -1071,7 +1124,7 @@ impl PrimitiveContainer {
     pub fn is_visible(&self) -> bool {
         match *self {
             PrimitiveContainer::TextRun(ref info) => {
-                info.font.color.a > 0
+                info.specified_font.color.a > 0
             }
             PrimitiveContainer::Brush(ref brush) => {
                 match brush.kind {
@@ -1100,7 +1153,7 @@ impl PrimitiveContainer {
             PrimitiveContainer::TextRun(ref info) => {
                 let mut font = FontInstance {
                     color: shadow.color.into(),
-                    ..info.font.clone()
+                    ..info.specified_font.clone()
                 };
                 if shadow.blur_radius > 0.0 {
                     font.disable_subpixel_aa();
@@ -1146,6 +1199,9 @@ pub struct PrimitiveStore {
 
     pub pictures: Vec<PicturePrimitive>,
     next_picture_id: u64,
+
+    /// A primitive index to chase through debugging.
+    pub chase_id: Option<PrimitiveIndex>,
 }
 
 impl PrimitiveStore {
@@ -1157,6 +1213,8 @@ impl PrimitiveStore {
 
             pictures: Vec::new(),
             next_picture_id: 0,
+
+            chase_id: None,
         }
     }
 
@@ -1168,6 +1226,8 @@ impl PrimitiveStore {
 
             pictures: recycle_vec(self.pictures),
             next_picture_id: self.next_picture_id,
+
+            chase_id: self.chase_id,
         }
     }
 
@@ -1213,7 +1273,7 @@ impl PrimitiveStore {
             clip_task_id: None,
             local_rect: *local_rect,
             local_clip_rect: *local_clip_rect,
-            clip_chain_rect_index: ClipChainRectIndex(0),
+            combined_local_clip_rect: *local_clip_rect,
             is_backface_visible,
             screen_rect: None,
             tag,
@@ -1495,7 +1555,7 @@ impl PrimitiveStore {
                 let transform = prim_run_context.scroll_node.world_content_transform.into();
                 text.prepare_for_render(
                     frame_context.device_pixel_scale,
-                    transform,
+                    &transform,
                     pic_context.allow_subpixel_aa,
                     pic_context.display_list,
                     frame_state,
@@ -1644,7 +1704,9 @@ impl PrimitiveStore {
                                 // Tighten the clip rect because decomposing the repeated image can
                                 // produce primitives that are partially covering the original image
                                 // rect and we want to clip these extra parts out.
-                                let tight_clip_rect = metadata.local_clip_rect.intersection(&metadata.local_rect).unwrap();
+                                let tight_clip_rect = metadata
+                                    .combined_local_clip_rect
+                                    .intersection(&metadata.local_rect).unwrap();
 
                                 let visible_rect = compute_conservative_visible_rect(
                                     prim_run_context,
@@ -1684,8 +1746,6 @@ impl PrimitiveStore {
 
                                                 let mut handle = GpuCacheHandle::new();
                                                 if let Some(mut request) = frame_state.gpu_cache.request(&mut handle) {
-                                                    request.push(*tile_rect);
-                                                    request.push(tight_clip_rect);
                                                     request.push(ColorF::new(1.0, 1.0, 1.0, opacity_binding.current).premultiplied());
                                                     request.push(PremultipliedColorF::WHITE);
                                                     request.push([tile_rect.size.width, tile_rect.size.height, 0.0, 0.0]);
@@ -1696,6 +1756,8 @@ impl PrimitiveStore {
                                                     tile_offset,
                                                     handle,
                                                     edge_flags: tile_flags & edge_flags,
+                                                    local_rect: *tile_rect,
+                                                    local_clip_rect: tight_clip_rect,
                                                 });
                                             }
                                         );
@@ -1789,9 +1851,7 @@ impl PrimitiveStore {
                                 prim_run_context,
                                 frame_context,
                                 frame_state,
-                                &mut |rect, clip_rect, mut request| {
-                                    request.push(*rect);
-                                    request.push(*clip_rect);
+                                &mut |rect, mut request| {
                                     request.push([
                                         center.x,
                                         center.y,
@@ -1841,9 +1901,7 @@ impl PrimitiveStore {
                                 prim_run_context,
                                 frame_context,
                                 frame_state,
-                                &mut |rect, clip_rect, mut request| {
-                                    request.push(*rect);
-                                    request.push(*clip_rect);
+                                &mut |rect, mut request| {
                                     request.push([
                                         start_point.x,
                                         start_point.y,
@@ -1895,10 +1953,6 @@ impl PrimitiveStore {
 
         // Mark this GPU resource as required for this frame.
         if let Some(mut request) = frame_state.gpu_cache.request(&mut metadata.gpu_location) {
-            // has to match VECS_PER_BRUSH_PRIM
-            request.push(metadata.local_rect);
-            request.push(metadata.local_clip_rect);
-
             match metadata.prim_kind {
                 PrimitiveKind::TextRun => {
                     let text = &self.cpu_text_runs[metadata.cpu_prim_index.0];
@@ -2042,11 +2096,11 @@ impl PrimitiveStore {
                 // node and the primitive, we need to get the clip rect in the
                 // local space of the primitive, in order to generate correct
                 // local segments.
-                let local_clip_rect = if clip_item.scroll_node_data_index == prim_run_context.scroll_node.node_data_index {
+                let local_clip_rect = if clip_item.transform_index == prim_run_context.scroll_node.transform_index {
                     local_clip_rect
                 } else {
                     let clip_transform = frame_context
-                        .node_data[clip_item.scroll_node_data_index.0 as usize]
+                        .transforms[clip_item.transform_index.0 as usize]
                         .transform;
                     let prim_transform = &prim_run_context.scroll_node.world_content_transform;
                     let relative_transform = prim_transform
@@ -2193,12 +2247,19 @@ impl PrimitiveStore {
         frame_context: &FrameBuildingContext,
         frame_state: &mut FrameBuildingState,
     ) -> bool {
+        if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+            println!("\tupdating clip task with screen rect {:?}", prim_screen_rect);
+        }
         // Reset clips from previous frames since we may clip differently each frame.
         self.reset_clip_task(prim_index);
 
         let prim_screen_rect = match prim_screen_rect.intersection(&frame_context.screen_rect) {
             Some(rect) => rect,
             None => {
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tculled by the intersection with frame rect {:?}",
+                        frame_context.screen_rect);
+                }
                 self.cpu_metadata[prim_index.0].screen_rect = None;
                 return false;
             }
@@ -2207,6 +2268,9 @@ impl PrimitiveStore {
         let mut combined_outer_rect =
             prim_screen_rect.intersection(&prim_run_context.clip_chain.combined_outer_screen_rect);
         let clip_chain = prim_run_context.clip_chain.nodes.clone();
+        if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+            println!("\tbase combined outer rect {:?}", combined_outer_rect);
+        }
 
         let prim_coordinate_system_id = prim_run_context.scroll_node.coordinate_system_id;
         let transform = &prim_run_context.scroll_node.world_content_transform;
@@ -2228,10 +2292,13 @@ impl PrimitiveStore {
                 if let Some(outer) = screen_outer_rect {
                     combined_outer_rect = combined_outer_rect.and_then(|r| r.intersection(&outer));
                 }
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tfound extra clip with screen bounds {:?}", screen_outer_rect);
+                }
 
                 Arc::new(ClipChainNode {
                     work_item: ClipWorkItem {
-                        scroll_node_data_index: prim_run_context.scroll_node.node_data_index,
+                        transform_index: prim_run_context.scroll_node.transform_index,
                         clip_sources: clip_sources.weak(),
                         coordinate_system_id: prim_coordinate_system_id,
                     },
@@ -2251,6 +2318,9 @@ impl PrimitiveStore {
         let combined_outer_rect = match combined_outer_rect {
             Some(rect) if !rect.is_empty() => rect,
             _ => {
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tculled by the empty combined screen rect");
+                }
                 self.cpu_metadata[prim_index.0].screen_rect = None;
                 return false;
             }
@@ -2274,12 +2344,18 @@ impl PrimitiveStore {
             // If we don't have any clips from other coordinate systems, the local clip
             // calculated from the clip chain should be sufficient to ensure proper clipping.
             if !has_clips_from_other_coordinate_systems {
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tneed no task: all clips are within the coordinate system");
+                }
                 return true;
             }
 
             // If we have filtered all clips and the screen rect isn't any smaller, we can just
             // skip masking entirely.
             if combined_outer_rect == prim_screen_rect {
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tneed no task: combined rect is not smaller");
+                }
                 return true;
             }
             // Otherwise we create an empty mask, but with an empty inner rect to avoid further
@@ -2288,7 +2364,10 @@ impl PrimitiveStore {
         }
 
         if combined_inner_rect.contains_rect(&prim_screen_rect) {
-           return true;
+            if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                println!("\tneed no task: contained within the clip inner rect");
+            }
+            return true;
         }
 
         // First try to  render this primitive's mask using optimized brush rendering.
@@ -2302,6 +2381,9 @@ impl PrimitiveStore {
             frame_context,
             frame_state,
         ) {
+            if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                println!("\tsegment tasks have been created for clipping");
+            }
             return true;
         }
 
@@ -2316,6 +2398,10 @@ impl PrimitiveStore {
         );
 
         let clip_task_id = frame_state.render_tasks.add(clip_task);
+        if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+            println!("\tcreated task {:?} with combined outer rect {:?}",
+                clip_task_id, combined_outer_rect);
+        }
         self.cpu_metadata[prim_index.0].clip_task_id = Some(clip_task_id);
         pic_state.tasks.push(clip_task_id);
 
@@ -2341,6 +2427,9 @@ impl PrimitiveStore {
 
             if !metadata.is_backface_visible &&
                prim_run_context.scroll_node.world_content_transform.is_backface_visible() {
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tculled for not having visible back faces");
+                }
                 return None;
             }
 
@@ -2358,6 +2447,9 @@ impl PrimitiveStore {
                     let pic = &mut self.pictures[pic_index.0];
 
                     if !pic.resolve_scene_properties(frame_context.scene_properties) {
+                        if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                            println!("\tculled for carrying an invisible composite filter");
+                        }
                         return None;
                     }
 
@@ -2429,7 +2521,9 @@ impl PrimitiveStore {
             let metadata = &mut self.cpu_metadata[prim_index.0];
             if metadata.local_rect.size.width <= 0.0 ||
                metadata.local_rect.size.height <= 0.0 {
-                //warn!("invalid primitive rect {:?}", metadata.local_rect);
+                if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                    println!("\tculled for zero local rectangle");
+                }
                 return None;
             }
 
@@ -2441,14 +2535,33 @@ impl PrimitiveStore {
             // taken into account.
             let local_rect = metadata.local_rect
                 .inflate(pic_context.inflation_factor, pic_context.inflation_factor)
-                .intersection(&metadata.local_clip_rect)?;
+                .intersection(&metadata.local_clip_rect);
+            let local_rect = match local_rect {
+                Some(local_rect) => local_rect,
+                None => {
+                    if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                        println!("\tculled for being out of the local clip rectangle: {:?}",
+                            metadata.local_clip_rect);
+                    }
+                    return None
+                }
+            };
 
-            let unclipped = calculate_screen_bounding_rect(
+            let unclipped = match calculate_screen_bounding_rect(
                 &prim_run_context.scroll_node.world_content_transform,
                 &local_rect,
                 frame_context.device_pixel_scale,
                 None, //TODO: inflate `frame_context.screen_rect` appropriately
-            )?;
+            ) {
+                Some(rect) => rect,
+                None => {
+                    if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+                        println!("\tculled for being behind the near plane of transform: {:?}",
+                            prim_run_context.scroll_node.world_content_transform);
+                    }
+                    return None
+                }
+            };
 
             let clipped = unclipped
                 .intersection(&prim_run_context.clip_chain.combined_outer_screen_rect)?;
@@ -2457,7 +2570,11 @@ impl PrimitiveStore {
                 clipped,
                 unclipped,
             });
-            metadata.clip_chain_rect_index = prim_run_context.clip_chain_rect_index;
+
+            metadata.combined_local_clip_rect = prim_run_context
+                .local_clip_rect
+                .intersection(&metadata.local_clip_rect)
+                .unwrap_or(LayoutRect::zero());
 
             (local_rect, unclipped)
         };
@@ -2480,6 +2597,10 @@ impl PrimitiveStore {
             return None;
         }
 
+        if cfg!(debug_assertions) && Some(prim_index) == self.chase_id {
+            println!("\tconsidered visible and ready with local rect {:?}", local_rect);
+        }
+
         self.prepare_prim_for_render_inner(
             prim_index,
             prim_run_context,
@@ -2514,6 +2635,10 @@ impl PrimitiveStore {
         };
 
         for run in &pic_context.prim_runs {
+            if run.is_chasing(self.chase_id) {
+                println!("\tpreparing a run of length {} in pipeline {:?}",
+                    run.count, pic_context.pipeline_id);
+            }
             // TODO(gw): Perhaps we can restructure this to not need to create
             //           a new primitive context for every run (if the hash
             //           lookups ever show up in a profile).
@@ -2531,12 +2656,16 @@ impl PrimitiveStore {
             pic_state.has_non_root_coord_system |= clip_chain.has_non_root_coord_system;
 
             if !scroll_node.invertible {
-                debug!("{:?} {:?}: position not invertible", run.base_prim_index, pic_context.pipeline_id);
+                if run.is_chasing(self.chase_id) {
+                    println!("\tculled for the scroll node transform being invertible");
+                }
                 continue;
             }
 
             if clip_chain.combined_outer_screen_rect.is_empty() {
-                debug!("{:?} {:?}: clipped out", run.base_prim_index, pic_context.pipeline_id);
+                if run.is_chasing(self.chase_id) {
+                    println!("\tculled for out of screen bounds");
+                }
                 continue;
             }
 
@@ -2565,19 +2694,16 @@ impl PrimitiveStore {
                 None
             };
 
-            let clip_chain_rect_index = match clip_chain_rect {
+            let local_clip_chain_rect = match clip_chain_rect {
                 Some(rect) if rect.is_empty() => continue,
-                Some(rect) => {
-                    frame_state.local_clip_rects.push(rect);
-                    ClipChainRectIndex(frame_state.local_clip_rects.len() - 1)
-                }
-                None => ClipChainRectIndex(0), // This is no clipping.
+                Some(rect) => rect,
+                None => frame_context.max_local_clip,
             };
 
             let child_prim_run_context = PrimitiveRunContext::new(
                 clip_chain,
                 scroll_node,
-                clip_chain_rect_index,
+                local_clip_chain_rect,
             );
 
             for i in 0 .. run.count {
@@ -2611,6 +2737,12 @@ impl PrimitiveStore {
                         result.local_rect_in_original_parent_space =
                             result.local_rect_in_original_parent_space.union(&bounds);
                     }
+
+                    if let Some(ref matrix) = parent_relative_transform {
+                        let bounds = matrix.transform_rect(&prim_local_rect);
+                        result.local_rect_in_actual_parent_space =
+                            result.local_rect_in_actual_parent_space.union(&bounds);
+                    }
                 }
             }
         }
@@ -2646,14 +2778,16 @@ fn decompose_repeated_primitive(
     prim_run_context: &PrimitiveRunContext,
     frame_context: &FrameBuildingContext,
     frame_state: &mut FrameBuildingState,
-    callback: &mut FnMut(&LayoutRect, &LayoutRect, GpuDataRequest),
+    callback: &mut FnMut(&LayoutRect, GpuDataRequest),
 ) {
     visible_tiles.clear();
 
     // Tighten the clip rect because decomposing the repeated image can
     // produce primitives that are partially covering the original image
     // rect and we want to clip these extra parts out.
-    let tight_clip_rect = metadata.local_clip_rect.intersection(&metadata.local_rect).unwrap();
+    let tight_clip_rect = metadata
+        .combined_local_clip_rect
+        .intersection(&metadata.local_rect).unwrap();
 
     let visible_rect = compute_conservative_visible_rect(
         prim_run_context,
@@ -2669,16 +2803,19 @@ fn decompose_repeated_primitive(
         &mut |origin, _| {
 
             let mut handle = GpuCacheHandle::new();
+            let rect = LayoutRect {
+                origin: *origin,
+                size: *stretch_size,
+            };
             if let Some(request) = frame_state.gpu_cache.request(&mut handle) {
-                let rect = LayoutRect {
-                    origin: *origin,
-                    size: *stretch_size,
-                };
-
-                callback(&rect, &tight_clip_rect, request);
+                callback(&rect, request);
             }
 
-            visible_tiles.push(VisibleGradientTile { handle });
+            visible_tiles.push(VisibleGradientTile {
+                local_rect: rect,
+                local_clip_rect: tight_clip_rect,
+                handle
+            });
         }
     );
 
@@ -2725,31 +2862,6 @@ fn edge_flags_for_tile_spacing(tile_spacing: &LayoutSize) -> EdgeAaSegmentMask {
     flags
 }
 
-//Test for one clip region contains another
-trait InsideTest<T> {
-    fn might_contain(&self, clip: &T) -> bool;
-}
-
-impl InsideTest<ComplexClipRegion> for ComplexClipRegion {
-    // Returns true if clip is inside self, can return false negative
-    fn might_contain(&self, clip: &ComplexClipRegion) -> bool {
-        let delta_left = clip.rect.origin.x - self.rect.origin.x;
-        let delta_top = clip.rect.origin.y - self.rect.origin.y;
-        let delta_right = self.rect.max_x() - clip.rect.max_x();
-        let delta_bottom = self.rect.max_y() - clip.rect.max_y();
-
-        delta_left >= 0f32 && delta_top >= 0f32 && delta_right >= 0f32 && delta_bottom >= 0f32 &&
-            clip.radii.top_left.width >= self.radii.top_left.width - delta_left &&
-            clip.radii.top_left.height >= self.radii.top_left.height - delta_top &&
-            clip.radii.top_right.width >= self.radii.top_right.width - delta_right &&
-            clip.radii.top_right.height >= self.radii.top_right.height - delta_top &&
-            clip.radii.bottom_left.width >= self.radii.bottom_left.width - delta_left &&
-            clip.radii.bottom_left.height >= self.radii.bottom_left.height - delta_bottom &&
-            clip.radii.bottom_right.width >= self.radii.bottom_right.width - delta_right &&
-            clip.radii.bottom_right.height >= self.radii.bottom_right.height - delta_bottom
-    }
-}
-
 fn convert_clip_chain_to_clip_vector(
     clip_chain_nodes: ClipChainNodeRef,
     extra_clip: ClipChainNodeRef,

gfx/webrender/src/render_backend.rs

@@ -1063,6 +1063,7 @@ impl RenderBackend {
 
         debug_assert!(op.render || !op.composite);
 
+        let mut render_time = None;
         if op.render && doc.has_pixels() {
             profile_scope!("generate frame");
 
@@ -1071,6 +1072,7 @@ impl RenderBackend {
             // borrow ck hack for profile_counters
             let (pending_update, rendered_document) = {
                 let _timer = profile_counters.total_time.timer();
+                let render_start_time = precise_time_ns();
 
                 let rendered_document = doc.render(
                     &mut self.resource_cache,
@@ -1085,6 +1087,8 @@ impl RenderBackend {
                 let msg = ResultMsg::UpdateGpuCache(self.gpu_cache.extract_updates());
                 self.result_tx.send(msg).unwrap();
 
+                render_time = Some(precise_time_ns() - render_start_time);
+
                 let pending_update = self.resource_cache.pending_updates();
                 (pending_update, rendered_document)
             };
@@ -1111,7 +1115,7 @@ impl RenderBackend {
         }
 
         if transaction_msg.generate_frame {
-            self.notifier.new_frame_ready(document_id, op.scroll, op.composite);
+            self.notifier.new_frame_ready(document_id, op.scroll, op.composite, render_time);
         }
     }
 
@@ -1410,7 +1414,7 @@ impl RenderBackend {
             self.result_tx.send(msg_publish).unwrap();
             profile_counters.reset();
 
-            self.notifier.new_frame_ready(id, false, true);
+            self.notifier.new_frame_ready(id, false, true, None);
             self.documents.insert(id, doc);
         }
     }

gfx/webrender/src/renderer.rs

@@ -26,7 +26,7 @@ use device::{FileWatcherHandler, ShaderError, TextureFilter,
              VertexUsageHint, VAO, VBO, CustomVAO};
 use device::{ProgramCache, ReadPixelsFormat};
 use euclid::{rect, Transform3D};
-use frame_builder::FrameBuilderConfig;
+use frame_builder::{ChasePrimitive, FrameBuilderConfig};
 use gleam::gl;
 use glyph_rasterizer::{GlyphFormat, GlyphRasterizer};
 use gpu_cache::{GpuBlockData, GpuCacheUpdate, GpuCacheUpdateList};
@@ -270,14 +270,15 @@ pub(crate) enum TextureSampler {
     CacheA8,
     CacheRGBA8,
     ResourceCache,
-    ClipScrollNodes,
+    TransformPalette,
     RenderTasks,
     Dither,
     // A special sampler that is bound to the A8 output of
     // the *first* pass. Items rendered in this target are
     // available as inputs to tasks in any subsequent pass.
     SharedCacheA8,
-    LocalClipRects
+    PrimitiveHeadersF,
+    PrimitiveHeadersI,
 }
 
 impl TextureSampler {
@@ -302,11 +303,12 @@ impl Into<TextureSlot> for TextureSampler {
             TextureSampler::CacheA8 => TextureSlot(3),
             TextureSampler::CacheRGBA8 => TextureSlot(4),
             TextureSampler::ResourceCache => TextureSlot(5),
-            TextureSampler::ClipScrollNodes => TextureSlot(6),
+            TextureSampler::TransformPalette => TextureSlot(6),
             TextureSampler::RenderTasks => TextureSlot(7),
             TextureSampler::Dither => TextureSlot(8),
             TextureSampler::SharedCacheA8 => TextureSlot(9),
-            TextureSampler::LocalClipRects => TextureSlot(10),
+            TextureSampler::PrimitiveHeadersF => TextureSlot(10),
+            TextureSampler::PrimitiveHeadersI => TextureSlot(11),
         }
     }
 }
@@ -330,12 +332,7 @@ pub(crate) mod desc {
         ],
         instance_attributes: &[
             VertexAttribute {
-                name: "aData0",
-                count: 4,
-                kind: VertexAttributeKind::I32,
-            },
-            VertexAttribute {
-                name: "aData1",
+                name: "aData",
                 count: 4,
                 kind: VertexAttributeKind::I32,
             },
@@ -1215,8 +1212,14 @@ struct VertexDataTexture {
 }
 
 impl VertexDataTexture {
-    fn new(device: &mut Device) -> VertexDataTexture {
-        let texture = device.create_texture(TextureTarget::Default, ImageFormat::RGBAF32);
+    fn new(
+        device: &mut Device,
+        format: ImageFormat,
+    ) -> VertexDataTexture {
+        let texture = device.create_texture(
+            TextureTarget::Default,
+            format,
+        );
         let pbo = device.create_pbo();
 
         VertexDataTexture { texture, pbo }
@@ -1369,8 +1372,9 @@ pub struct Renderer {
     pub gpu_profile: GpuProfiler<GpuProfileTag>,
     vaos: RendererVAOs,
 
-    node_data_texture: VertexDataTexture,
-    local_clip_rects_texture: VertexDataTexture,
+    prim_header_f_texture: VertexDataTexture,
+    prim_header_i_texture: VertexDataTexture,
+    transforms_texture: VertexDataTexture,
     render_task_texture: VertexDataTexture,
     gpu_cache_texture: CacheTexture,
 
@@ -1629,9 +1633,10 @@ impl Renderer {
 
         let texture_resolver = SourceTextureResolver::new(&mut device);
 
-        let node_data_texture = VertexDataTexture::new(&mut device);
-        let local_clip_rects_texture = VertexDataTexture::new(&mut device);
-        let render_task_texture = VertexDataTexture::new(&mut device);
+        let prim_header_f_texture = VertexDataTexture::new(&mut device, ImageFormat::RGBAF32);
+        let prim_header_i_texture = VertexDataTexture::new(&mut device, ImageFormat::RGBAI32);
+        let transforms_texture = VertexDataTexture::new(&mut device, ImageFormat::RGBAF32);
+        let render_task_texture = VertexDataTexture::new(&mut device, ImageFormat::RGBAF32);
 
         let gpu_cache_texture = CacheTexture::new(
             &mut device,
@@ -1653,6 +1658,7 @@ impl Renderer {
             default_font_render_mode,
             dual_source_blending_is_enabled: true,
             dual_source_blending_is_supported: ext_dual_source_blending,
+            chase_primitive: options.chase_primitive,
         };
 
         let device_pixel_ratio = options.device_pixel_ratio;
@@ -1784,8 +1790,9 @@ impl Renderer {
                 dash_and_dot_vao,
                 border_vao,
             },
-            node_data_texture,
-            local_clip_rects_texture,
+            transforms_texture,
+            prim_header_i_texture,
+            prim_header_f_texture,
             render_task_texture,
             pipeline_info: PipelineInfo::default(),
             dither_matrix_texture,
@@ -3533,16 +3540,31 @@ impl Renderer {
         let _timer = self.gpu_profile.start_timer(GPU_TAG_SETUP_DATA);
         self.device.set_device_pixel_ratio(frame.device_pixel_ratio);
 
-        self.node_data_texture.update(&mut self.device, &mut frame.node_data);
-        self.device.bind_texture(TextureSampler::ClipScrollNodes, &self.node_data_texture.texture);
-
-        self.local_clip_rects_texture.update(
+        self.prim_header_f_texture.update(
             &mut self.device,
-            &mut frame.clip_chain_local_clip_rects
+            &mut frame.prim_headers.headers_float,
         );
         self.device.bind_texture(
-            TextureSampler::LocalClipRects,
-            &self.local_clip_rects_texture.texture
+            TextureSampler::PrimitiveHeadersF,
+            &self.prim_header_f_texture.texture,
+        );
+
+        self.prim_header_i_texture.update(
+            &mut self.device,
+            &mut frame.prim_headers.headers_int,
+        );
+        self.device.bind_texture(
+            TextureSampler::PrimitiveHeadersI,
+            &self.prim_header_i_texture.texture,
+        );
+
+        self.transforms_texture.update(
+            &mut self.device,
+            &mut frame.transform_palette,
+        );
+        self.device.bind_texture(
+            TextureSampler::TransformPalette,
+            &self.transforms_texture.texture,
         );
 
         self.render_task_texture
@@ -3929,8 +3951,9 @@ impl Renderer {
         if let Some(dither_matrix_texture) = self.dither_matrix_texture {
             self.device.delete_texture(dither_matrix_texture);
         }
-        self.node_data_texture.deinit(&mut self.device);
-        self.local_clip_rects_texture.deinit(&mut self.device);
+        self.transforms_texture.deinit(&mut self.device);
+        self.prim_header_f_texture.deinit(&mut self.device);
+        self.prim_header_i_texture.deinit(&mut self.device);
         self.render_task_texture.deinit(&mut self.device);
         self.device.delete_pbo(self.texture_cache_upload_pbo);
         self.texture_resolver.deinit(&mut self.device);
@@ -4017,11 +4040,11 @@ pub trait SceneBuilderHooks {
     /// and before it processes anything.
     fn register(&self);
     /// This is called before each scene swap occurs.
-    fn pre_scene_swap(&self);
+    fn pre_scene_swap(&self, scenebuild_time: u64);
     /// This is called after each scene swap occurs. The PipelineInfo contains
     /// the updated epochs and pipelines removed in the new scene compared to
     /// the old scene.
-    fn post_scene_swap(&self, info: PipelineInfo);
+    fn post_scene_swap(&self, info: PipelineInfo, sceneswap_time: u64);
     /// This is called after a resource update operation on the scene builder
     /// thread, in the case where resource updates were applied without a scene
     /// build.
@@ -4078,6 +4101,7 @@ pub struct RendererOptions {
     pub disable_dual_source_blending: bool,
     pub scene_builder_hooks: Option<Box<SceneBuilderHooks + Send>>,
     pub sampler: Option<Box<AsyncPropertySampler + Send>>,
+    pub chase_primitive: ChasePrimitive,
 }
 
 impl Default for RendererOptions {
@@ -4111,6 +4135,7 @@ impl Default for RendererOptions {
             disable_dual_source_blending: false,
             scene_builder_hooks: None,
             sampler: None,
+            chase_primitive: ChasePrimitive::Nothing,
         }
     }
 }

gfx/webrender/src/resource_cache.rs

@@ -641,13 +641,20 @@ impl ResourceCache {
             return
         };
 
+        if !self.pending_image_requests.insert(request) {
+            return
+        }
+
+        // If we are tiling, then we need to confirm the dirty rect intersects
+        // the tile before leaving the request in the pending queue.
+        //
         // We can start a worker thread rasterizing right now, if:
         //  - The image is a blob.
         //  - The blob hasn't already been requested this frame.
-        if self.pending_image_requests.insert(request) && template.data.is_blob() {
-            let (offset, size) = match template.tiling {
-                Some(tile_size) => {
-                    let tile_offset = request.tile.unwrap();
+        if template.data.is_blob() || dirty_rect.is_some() {
+            let (offset, size) = match request.tile {
+                Some(tile_offset) => {
+                    let tile_size = template.tiling.unwrap();
                     let actual_size = compute_tile_size(
                         &template.descriptor,
                         tile_size,
@@ -671,17 +678,19 @@ impl ResourceCache {
                 None => (DevicePoint::zero(), template.descriptor.size),
             };
 
-            if let Some(ref mut renderer) = self.blob_image_renderer {
-                renderer.request(
-                    &self.resources,
-                    request.into(),
-                    &BlobImageDescriptor {
-                        size,
-                        offset,
-                        format: template.descriptor.format,
-                    },
-                    dirty_rect,
-                );
+            if template.data.is_blob() {
+                if let Some(ref mut renderer) = self.blob_image_renderer {
+                    renderer.request(
+                        &self.resources,
+                        request.into(),
+                        &BlobImageDescriptor {
+                            size,
+                            offset,
+                            format: template.descriptor.format,
+                        },
+                        dirty_rect,
+                    );
+                }
             }
         }
     }
@@ -923,6 +932,8 @@ impl ResourceCache {
     }
 
     fn update_texture_cache(&mut self, gpu_cache: &mut GpuCache) {
+        let mut keys_to_clear_dirty_rect = FastHashSet::default();
+
         for request in self.pending_image_requests.drain() {
             let image_template = self.resources.image_templates.get_mut(request.key).unwrap();
             debug_assert!(image_template.data.uses_texture_cache());
@@ -963,23 +974,24 @@ impl ResourceCache {
 
             let entry = self.cached_images.get_mut(&request).as_mut().unwrap();
             let mut descriptor = image_template.descriptor.clone();
-            //TODO: erasing the dirty rectangle here is incorrect for tiled images,
-            // since other tile requests may follow that depend on it
-            let mut local_dirty_rect = image_template.dirty_rect.take();
+            let local_dirty_rect;
 
             if let Some(tile) = request.tile {
                 let tile_size = image_template.tiling.unwrap();
                 let clipped_tile_size = compute_tile_size(&descriptor, tile_size, tile);
 
-                if let Some(ref mut rect) = local_dirty_rect {
-                    match intersect_for_tile(*rect, clipped_tile_size, tile_size, tile) {
-                        Some(intersection) => *rect = intersection,
-                        None => {
-                            // if re-uploaded, the dirty rect is ignored anyway
-                            debug_assert!(self.texture_cache.needs_upload(&entry.texture_cache_handle))
-                        }
-                    }
-                }
+                local_dirty_rect = if let Some(ref rect) = image_template.dirty_rect {
+                    keys_to_clear_dirty_rect.insert(request.key.clone());
+
+                    // We should either have a dirty rect, or we are re-uploading where the dirty
+                    // rect is ignored anyway.
+                    let intersection = intersect_for_tile(*rect, clipped_tile_size, tile_size, tile);
+                    debug_assert!(intersection.is_some() ||
+                                  self.texture_cache.needs_upload(&entry.texture_cache_handle));
+                    intersection
+                } else {
+                    None
+                };
 
                 // The tiled image could be stored on the CPU as one large image or be
                 // already broken up into tiles. This affects the way we compute the stride
@@ -995,6 +1007,8 @@ impl ResourceCache {
                 }
 
                 descriptor.size = clipped_tile_size;
+            } else {
+                local_dirty_rect = image_template.dirty_rect.take();
             }
 
             let filter = match request.rendering {
@@ -1036,6 +1050,11 @@ impl ResourceCache {
                 UvRectKind::Rect,
             );
         }
+
+        for key in keys_to_clear_dirty_rect.drain() {
+            let image_template = self.resources.image_templates.get_mut(key).unwrap();
+            image_template.dirty_rect.take();
+        }
     }
 
     pub fn end_frame(&mut self) {

gfx/webrender/src/scene_builder.rs

@@ -13,6 +13,7 @@ use render_backend::DocumentView;
 use renderer::{PipelineInfo, SceneBuilderHooks};
 use scene::Scene;
 use std::sync::mpsc::{channel, Receiver, Sender};
+use time::precise_time_ns;
 
 // Message from render backend to scene builder.
 pub enum SceneBuilderRequest {
@@ -137,6 +138,7 @@ impl SceneBuilder {
                 frame_ops,
                 render,
             } => {
+                let scenebuild_start_time = precise_time_ns();
                 let built_scene = scene.map(|request|{
                     build_scene(&self.config, request)
                 });
@@ -156,13 +158,15 @@ impl SceneBuilder {
                         };
                         let (tx, rx) = channel();
 
-                        hooks.pre_scene_swap();
+                        let scenebuild_time = precise_time_ns() - scenebuild_start_time;
+                        hooks.pre_scene_swap(scenebuild_time);
 
                         (Some(info), Some(tx), Some(rx))
                     }
                     _ => (None, None, None),
                 };
 
+                let sceneswap_start_time = precise_time_ns();
                 let has_resources_updates = !resource_updates.is_empty();
                 self.tx.send(SceneBuilderResult::Transaction {
                     document_id,
@@ -178,7 +182,8 @@ impl SceneBuilder {
                 if let Some(pipeline_info) = pipeline_info {
                     // Block until the swap is done, then invoke the hook.
                     let swap_result = result_rx.unwrap().recv();
-                    self.hooks.as_ref().unwrap().post_scene_swap(pipeline_info);
+                    let sceneswap_time = precise_time_ns() - sceneswap_start_time;
+                    self.hooks.as_ref().unwrap().post_scene_swap(pipeline_info, sceneswap_time);
                     // Once the hook is done, allow the RB thread to resume
                     match swap_result {
                         Ok(SceneSwapResult::Complete(resume_tx)) => {

gfx/webrender/src/shade.rs

@@ -351,11 +351,12 @@ fn create_prim_shader(
                 ("sDither", TextureSampler::Dither),
                 ("sCacheA8", TextureSampler::CacheA8),
                 ("sCacheRGBA8", TextureSampler::CacheRGBA8),
-                ("sClipScrollNodes", TextureSampler::ClipScrollNodes),
+                ("sTransformPalette", TextureSampler::TransformPalette),
                 ("sRenderTasks", TextureSampler::RenderTasks),
                 ("sResourceCache", TextureSampler::ResourceCache),
                 ("sSharedCacheA8", TextureSampler::SharedCacheA8),
-                ("sLocalClipRects", TextureSampler::LocalClipRects),
+                ("sPrimitiveHeadersF", TextureSampler::PrimitiveHeadersF),
+                ("sPrimitiveHeadersI", TextureSampler::PrimitiveHeadersI),
             ],
         );
     }
@@ -379,11 +380,12 @@ fn create_clip_shader(name: &'static str, device: &mut Device) -> Result<Program
             program,
             &[
                 ("sColor0", TextureSampler::Color0),
-                ("sClipScrollNodes", TextureSampler::ClipScrollNodes),
+                ("sTransformPalette", TextureSampler::TransformPalette),
                 ("sRenderTasks", TextureSampler::RenderTasks),
                 ("sResourceCache", TextureSampler::ResourceCache),
                 ("sSharedCacheA8", TextureSampler::SharedCacheA8),
-                ("sLocalClipRects", TextureSampler::LocalClipRects),
+                ("sPrimitiveHeadersF", TextureSampler::PrimitiveHeadersF),
+                ("sPrimitiveHeadersI", TextureSampler::PrimitiveHeadersI),
             ],
         );
     }

gfx/webrender/src/texture_cache.rs

@@ -501,6 +501,7 @@ impl TextureCache {
             (ImageFormat::BGRA8, TextureFilter::Nearest) => &mut self.array_rgba8_nearest,
             (ImageFormat::RGBAF32, _) |
             (ImageFormat::RG8, _) |
+            (ImageFormat::RGBAI32, _) |
             (ImageFormat::R8, TextureFilter::Nearest) |
             (ImageFormat::R8, TextureFilter::Trilinear) |
             (ImageFormat::BGRA8, TextureFilter::Trilinear) => unreachable!(),
@@ -725,6 +726,7 @@ impl TextureCache {
             (ImageFormat::BGRA8, TextureFilter::Linear) => &mut self.array_rgba8_linear,
             (ImageFormat::BGRA8, TextureFilter::Nearest) => &mut self.array_rgba8_nearest,
             (ImageFormat::RGBAF32, _) |
+            (ImageFormat::RGBAI32, _) |
             (ImageFormat::R8, TextureFilter::Nearest) |
             (ImageFormat::R8, TextureFilter::Trilinear) |
             (ImageFormat::BGRA8, TextureFilter::Trilinear) |

gfx/webrender/src/tiling.rs

@@ -12,8 +12,7 @@ use device::{FrameId, Texture};
 #[cfg(feature = "pathfinder")]
 use euclid::{TypedPoint2D, TypedVector2D};
 use gpu_cache::{GpuCache};
-use gpu_types::{BorderInstance, BlurDirection, BlurInstance};
-use gpu_types::{ClipScrollNodeData, ZBufferIdGenerator};
+use gpu_types::{BorderInstance, BlurDirection, BlurInstance, PrimitiveHeaders, TransformData, TransformPalette};
 use internal_types::{FastHashMap, SavedTargetIndex, SourceTexture};
 #[cfg(feature = "pathfinder")]
 use pathfinder_partitioner::mesh::Mesh;
@@ -48,7 +47,7 @@ pub struct RenderTargetContext<'a, 'rc> {
     pub resource_cache: &'rc mut ResourceCache,
     pub clip_scroll_tree: &'a ClipScrollTree,
     pub use_dual_source_blending: bool,
-    pub node_data: &'a [ClipScrollNodeData],
+    pub transforms: &'a TransformPalette,
 }
 
 #[cfg_attr(feature = "capture", derive(Serialize))]
@@ -103,6 +102,7 @@ pub trait RenderTarget {
         _gpu_cache: &mut GpuCache,
         _render_tasks: &mut RenderTaskTree,
         _deferred_resolves: &mut Vec<DeferredResolve>,
+        _prim_headers: &mut PrimitiveHeaders,
     ) {
     }
     // TODO(gw): It's a bit odd that we need the deferred resolves and mutable
@@ -166,12 +166,19 @@ impl<T: RenderTarget> RenderTargetList<T> {
         render_tasks: &mut RenderTaskTree,
         deferred_resolves: &mut Vec<DeferredResolve>,
         saved_index: Option<SavedTargetIndex>,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
         debug_assert_eq!(None, self.saved_index);
         self.saved_index = saved_index;
 
         for target in &mut self.targets {
-            target.build(ctx, gpu_cache, render_tasks, deferred_resolves);
+            target.build(
+                ctx,
+                gpu_cache,
+                render_tasks,
+                deferred_resolves,
+                prim_headers,
+            );
         }
     }
 
@@ -333,9 +340,9 @@ impl RenderTarget for ColorRenderTarget {
         gpu_cache: &mut GpuCache,
         render_tasks: &mut RenderTaskTree,
         deferred_resolves: &mut Vec<DeferredResolve>,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
         let mut merged_batches = AlphaBatchContainer::new(None);
-        let mut z_generator = ZBufferIdGenerator::new();
 
         for task_id in &self.alpha_tasks {
             let task = &render_tasks[*task_id];
@@ -358,7 +365,7 @@ impl RenderTarget for ColorRenderTarget {
                                 gpu_cache,
                                 render_tasks,
                                 deferred_resolves,
-                                &mut z_generator,
+                                prim_headers,
                             );
 
                             if let Some(batch_container) = batch_builder.build(&mut merged_batches) {
@@ -594,6 +601,7 @@ impl RenderTarget for AlphaRenderTarget {
                     ctx.resource_cache,
                     gpu_cache,
                     clip_store,
+                    ctx.transforms,
                 );
             }
             RenderTaskKind::ClipRegion(ref task) => {
@@ -795,6 +803,7 @@ impl RenderPass {
         render_tasks: &mut RenderTaskTree,
         deferred_resolves: &mut Vec<DeferredResolve>,
         clip_store: &ClipStore,
+        prim_headers: &mut PrimitiveHeaders,
     ) {
         profile_scope!("RenderPass::build");
 
@@ -811,7 +820,13 @@ impl RenderPass {
                         deferred_resolves,
                     );
                 }
-                target.build(ctx, gpu_cache, render_tasks, deferred_resolves);
+                target.build(
+                    ctx,
+                    gpu_cache,
+                    render_tasks,
+                    deferred_resolves,
+                    prim_headers,
+                );
             }
             RenderPassKind::OffScreen { ref mut color, ref mut alpha, ref mut texture_cache } => {
                 let is_shared_alpha = self.tasks.iter().any(|&task_id| {
@@ -911,8 +926,22 @@ impl RenderPass {
                     }
                 }
 
-                color.build(ctx, gpu_cache, render_tasks, deferred_resolves, saved_color);
-                alpha.build(ctx, gpu_cache, render_tasks, deferred_resolves, saved_alpha);
+                color.build(
+                    ctx,
+                    gpu_cache,
+                    render_tasks,
+                    deferred_resolves,
+                    saved_color,
+                    prim_headers,
+                );
+                alpha.build(
+                    ctx,
+                    gpu_cache,
+                    render_tasks,
+                    deferred_resolves,
+                    saved_alpha,
+                    prim_headers,
+                );
                 alpha.is_shared = is_shared_alpha;
             }
         }
@@ -956,9 +985,9 @@ pub struct Frame {
     #[cfg_attr(any(feature = "capture", feature = "replay"), serde(default = "FrameProfileCounters::new", skip))]
     pub profile_counters: FrameProfileCounters,
 
-    pub node_data: Vec<ClipScrollNodeData>,
-    pub clip_chain_local_clip_rects: Vec<LayoutRect>,
+    pub transform_palette: Vec<TransformData>,
     pub render_tasks: RenderTaskTree,
+    pub prim_headers: PrimitiveHeaders,
 
     /// The GPU cache frame that the contents of Self depend on
     pub gpu_cache_frame_id: FrameId,

gfx/webrender_api/src/api.rs

@@ -1103,7 +1103,7 @@ pub struct DynamicProperties {
 pub trait RenderNotifier: Send {
     fn clone(&self) -> Box<RenderNotifier>;
     fn wake_up(&self);
-    fn new_frame_ready(&self, DocumentId, scrolled: bool, composite_needed: bool);
+    fn new_frame_ready(&self, DocumentId, scrolled: bool, composite_needed: bool, render_time_ns: Option<u64>);
     fn external_event(&self, _evt: ExternalEvent) {
         unimplemented!()
     }

gfx/webrender_api/src/color.rs

@@ -115,7 +115,7 @@ pub struct ColorU {
 
 impl ColorU {
     /// Constructs a new additive `ColorU` from its components.
-    pub fn new(r: u8, g: u8, b: u8, a: u8) -> ColorU {
+    pub fn new(r: u8, g: u8, b: u8, a: u8) -> Self {
         ColorU { r, g, b, a }
     }
 }

gfx/webrender_api/src/display_item.rs

@@ -273,22 +273,10 @@ pub enum RepeatMode {
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]
-pub struct GradientBorder {
-    pub gradient: Gradient,
-    pub outset: SideOffsets2D<f32>,
-}
-
-#[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]
-pub struct RadialGradientBorder {
-    pub gradient: RadialGradient,
-    pub outset: SideOffsets2D<f32>,
-}
-
-#[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]
-/// TODO(mrobinson): Currently only images are supported, but we will
-/// eventually add support for Gradient and RadialGradient.
 pub enum NinePatchBorderSource {
     Image(ImageKey),
+    Gradient(Gradient),
+    RadialGradient(RadialGradient),
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]
@@ -333,8 +321,6 @@ pub struct NinePatchBorder {
 pub enum BorderDetails {
     Normal(NormalBorder),
     NinePatch(NinePatchBorder),
-    Gradient(GradientBorder),
-    RadialGradient(RadialGradientBorder),
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, PartialEq, Serialize)]

gfx/webrender_api/src/display_list.rs

@@ -27,8 +27,8 @@ use {StickyFrameDisplayItem, StickyOffsetBounds, TextDisplayItem, TransformStyle
 use {YuvData, YuvImageDisplayItem};
 
 // We don't want to push a long text-run. If a text-run is too long, split it into several parts.
-// This needs to be set to (renderer::MAX_VERTEX_TEXTURE_WIDTH - VECS_PER_PRIM_HEADER - VECS_PER_TEXT_RUN) * 2
-pub const MAX_TEXT_RUN_LENGTH: usize = 2038;
+// This needs to be set to (renderer::MAX_VERTEX_TEXTURE_WIDTH - VECS_PER_TEXT_RUN) * 2
+pub const MAX_TEXT_RUN_LENGTH: usize = 2040;
 
 // We start at 2, because the root reference is always 0 and the root scroll node is always 1.
 const FIRST_CLIP_ID: usize = 2;

gfx/webrender_api/src/image.rs

@@ -59,6 +59,7 @@ pub enum ImageFormat {
     BGRA8 = 3,
     RGBAF32 = 4,
     RG8 = 5,
+    RGBAI32 = 6,
 }
 
 impl ImageFormat {
@@ -68,6 +69,7 @@ impl ImageFormat {
             ImageFormat::BGRA8 => 4,
             ImageFormat::RGBAF32 => 16,
             ImageFormat::RG8 => 2,
+            ImageFormat::RGBAI32 => 16,
         }
     }
 }

gfx/webrender_bindings/revision.txt

@@ -1 +1 @@
-cf98ad4d63729c678a7575eb9bce36794da5e270
+cdfaaeb5f74e416f39af1081c9a676c752d23896

gfx/webrender_bindings/webrender_ffi_generated.h

@@ -93,6 +93,7 @@ enum class ImageFormat : uint32_t {
   BGRA8 = 3,
   RGBAF32 = 4,
   RG8 = 5,
+  RGBAI32 = 6,
 
   Sentinel /* this must be last for serialization purposes. */
 };

gfx/wrench/Cargo.toml

@@ -14,7 +14,7 @@ euclid = "0.17"
 gleam = "0.5"
 glutin = "0.15"
 app_units = "0.6"
-image = "0.18"
+image = "0.19"
 clap = { version = "2", features = ["yaml"] }
 lazy_static = "1"
 log = "0.4"

gfx/wrench/src/args.yaml

@@ -67,6 +67,10 @@ args:
   - no_batch:
       long: no-batch
       help: Disable batching of instanced draw calls
+  - chase:
+      long: chase
+      help: Chase a particular primitive matching the local rect
+      takes_value: true
 
 subcommands:
     - png:

gfx/wrench/src/main.rs

@@ -257,7 +257,7 @@ fn make_window(
                 })
                 .with_vsync(vsync);
             let window_builder = winit::WindowBuilder::new()
-                .with_title("WRech")
+                .with_title("WRench")
                 .with_multitouch()
                 .with_dimensions(size.width, size.height);
 
@@ -351,7 +351,11 @@ impl RenderNotifier for Notifier {
         self.tx.send(NotifierEvent::ShutDown).unwrap();
     }
 
-    fn new_frame_ready(&self, _: DocumentId, _scrolled: bool, composite_needed: bool) {
+    fn new_frame_ready(&self,
+                       _: DocumentId,
+                       _scrolled: bool,
+                       composite_needed: bool,
+                       _render_time: Option<u64>) {
         if composite_needed {
             self.wake_up();
         }
@@ -424,6 +428,20 @@ fn main() {
         })
         .unwrap_or(DeviceUintSize::new(1920, 1080));
     let zoom_factor = args.value_of("zoom").map(|z| z.parse::<f32>().unwrap());
+    let chase_primitive = match args.value_of("chase") {
+        Some(s) => {
+            let mut items = s
+                .split(',')
+                .map(|s| s.parse::<f32>().unwrap())
+                .collect::<Vec<_>>();
+            let rect = LayoutRect::new(
+                LayoutPoint::new(items[0], items[1]),
+                LayoutSize::new(items[2], items[3]),
+            );
+            webrender::ChasePrimitive::LocalRect(rect)
+        },
+        None => webrender::ChasePrimitive::Nothing,
+    };
 
     let mut events_loop = if args.is_present("headless") {
         None
@@ -462,6 +480,7 @@ fn main() {
         args.is_present("precache"),
         args.is_present("slow_subpixel"),
         zoom_factor.unwrap_or(1.0),
+        chase_primitive,
         notifier,
     );
 
@@ -634,17 +653,30 @@ fn render<'a>(
                         let path = PathBuf::from("../captures/wrench");
                         wrench.api.save_capture(path, CaptureBits::all());
                     }
-                    VirtualKeyCode::Up => {
+                    VirtualKeyCode::Up | VirtualKeyCode::Down => {
+                        let mut txn = Transaction::new();
+
+                        let offset = match vk {
+                            winit::VirtualKeyCode::Up => LayoutVector2D::new(0.0, 10.0),
+                            winit::VirtualKeyCode::Down => LayoutVector2D::new(0.0, -10.0),
+                            _ => unreachable!("Should not see non directional keys here.")
+                        };
+
+                        txn.scroll(ScrollLocation::Delta(offset), cursor_position);
+                        txn.generate_frame();
+                        wrench.api.send_transaction(wrench.document_id, txn);
+
+                        do_frame = true;
+                    }
+                    VirtualKeyCode::Add => {
                         let current_zoom = wrench.get_page_zoom();
                         let new_zoom_factor = ZoomFactor::new(current_zoom.get() + 0.1);
-
                         wrench.set_page_zoom(new_zoom_factor);
                         do_frame = true;
                     }
-                    VirtualKeyCode::Down => {
+                    VirtualKeyCode::Subtract => {
                         let current_zoom = wrench.get_page_zoom();
                         let new_zoom_factor = ZoomFactor::new((current_zoom.get() - 0.1).max(0.1));
-
                         wrench.set_page_zoom(new_zoom_factor);
                         do_frame = true;
                     }

gfx/wrench/src/wrench.rs

@@ -109,7 +109,10 @@ impl RenderNotifier for Notifier {
         self.update(false);
     }
 
-    fn new_frame_ready(&self, _: DocumentId, scrolled: bool, _composite_needed: bool) {
+    fn new_frame_ready(&self, _: DocumentId,
+                       scrolled: bool,
+                       _composite_needed: bool,
+                       _render_time: Option<u64>) {
         self.update(!scrolled);
     }
 }
@@ -180,6 +183,7 @@ impl Wrench {
         precache_shaders: bool,
         disable_dual_source_blending: bool,
         zoom_factor: f32,
+        chase_primitive: webrender::ChasePrimitive,
         notifier: Option<Box<RenderNotifier>>,
     ) -> Self {
         println!("Shader override path: {:?}", shader_override_path);
@@ -212,6 +216,7 @@ impl Wrench {
             precache_shaders,
             blob_image_renderer: Some(Box::new(blob::CheckerboardRenderer::new(callbacks.clone()))),
             disable_dual_source_blending,
+            chase_primitive,
             ..Default::default()
         };
 

gfx/wrench/src/yaml_frame_reader.rs

@@ -173,7 +173,8 @@ fn is_image_opaque(format: ImageFormat, bytes: &[u8]) -> bool {
         }
         ImageFormat::RG8 => true,
         ImageFormat::R8 => false,
-        ImageFormat::RGBAF32 => unreachable!(),
+        ImageFormat::RGBAF32 |
+        ImageFormat::RGBAI32 => unreachable!(),
     }
 }
 
@@ -880,26 +881,28 @@ impl YamlFrameReader {
                         radius,
                     }))
                 }
-                "image" => {
-                    let file = rsrc_path(&item["image-source"], &self.aux_dir);
-                    let (image_key, _) = self
-                        .add_or_get_image(&file, None, wrench);
+                "image" | "gradient" | "radial-gradient" => {
                     let image_width = item["image-width"]
                         .as_i64()
-                        .expect("border must have image-width");
+                        .unwrap_or(info.rect.size.width as i64);
                     let image_height = item["image-height"]
                         .as_i64()
-                        .expect("border must have image-height");
+                        .unwrap_or(info.rect.size.height as i64);
                     let fill = item["fill"].as_bool().unwrap_or(false);
-                    let slice = item["slice"].as_vec_u32().expect("border must have slice");
-                    let slice = broadcast(&slice, 4);
+
+                    let slice = item["slice"].as_vec_u32();
+                    let slice = match slice {
+                        Some(slice) => broadcast(&slice, 4),
+                        None => vec![widths.top as u32, widths.left as u32, widths.bottom as u32, widths.right as u32],
+                    };
+
                     let outset = item["outset"]
                         .as_vec_f32()
                         .expect("border must have outset");
                     let outset = broadcast(&outset, 4);
                     let repeat_horizontal = match item["repeat-horizontal"]
                         .as_str()
-                        .expect("border must have repeat-horizontal")
+                        .unwrap_or("stretch")
                     {
                         "stretch" => RepeatMode::Stretch,
                         "repeat" => RepeatMode::Repeat,
@@ -909,7 +912,7 @@ impl YamlFrameReader {
                     };
                     let repeat_vertical = match item["repeat-vertical"]
                         .as_str()
-                        .expect("border must have repeat-vertical")
+                        .unwrap_or("stretch")
                     {
                         "stretch" => RepeatMode::Stretch,
                         "repeat" => RepeatMode::Repeat,
@@ -917,8 +920,27 @@ impl YamlFrameReader {
                         "space" => RepeatMode::Space,
                         s => panic!("Unknown box border image repeat mode {}", s),
                     };
+                    let source = match border_type {
+                        "image" => {
+                            let file = rsrc_path(&item["image-source"], &self.aux_dir);
+                            let (image_key, _) = self
+                                .add_or_get_image(&file, None, wrench);
+                            NinePatchBorderSource::Image(image_key)
+                        }
+                        "gradient" => {
+                            let gradient = self.to_gradient(dl, item);
+                            NinePatchBorderSource::Gradient(gradient)
+                        }
+                        "radial-gradient" => {
+                            let gradient = self.to_radial_gradient(dl, item);
+                            NinePatchBorderSource::RadialGradient(gradient)
+
+                        }
+                        _ => unreachable!("Unexpected border type"),
+                    };
+
                     Some(BorderDetails::NinePatch(NinePatchBorder {
-                        source: NinePatchBorderSource::Image(image_key),
+                        source,
                         width: image_width as u32,
                         height: image_height as u32,
                         slice: SideOffsets2D::new(slice[0], slice[1], slice[2], slice[3]),
@@ -928,28 +950,6 @@ impl YamlFrameReader {
                         outset: SideOffsets2D::new(outset[0], outset[1], outset[2], outset[3]),
                     }))
                 }
-                "gradient" => {
-                    let gradient = self.to_gradient(dl, item);
-                    let outset = item["outset"]
-                        .as_vec_f32()
-                        .expect("borders must have outset");
-                    let outset = broadcast(&outset, 4);
-                    Some(BorderDetails::Gradient(GradientBorder {
-                        gradient,
-                        outset: SideOffsets2D::new(outset[0], outset[1], outset[2], outset[3]),
-                    }))
-                }
-                "radial-gradient" => {
-                    let gradient = self.to_radial_gradient(dl, item);
-                    let outset = item["outset"]
-                        .as_vec_f32()
-                        .expect("borders must have outset");
-                    let outset = broadcast(&outset, 4);
-                    Some(BorderDetails::RadialGradient(RadialGradientBorder {
-                        gradient,
-                        outset: SideOffsets2D::new(outset[0], outset[1], outset[2], outset[3]),
-                    }))
-                }
                 _ => {
                     println!("Unable to parse border {:?}", item);
                     None
@@ -1391,7 +1391,7 @@ impl YamlFrameReader {
             clip_rect,
             complex_clips,
             image_mask,
-            ScrollSensitivity::Script,
+            ScrollSensitivity::ScriptAndInputEvents,
         );
         if let Some(numeric_id) = numeric_id {
             self.add_clip_id_mapping(numeric_id, real_id);

gfx/wrench/src/yaml_frame_writer.rs

@@ -885,14 +885,35 @@ impl YamlFrameWriter {
                                 details.outset.left,
                             ];
                             yaml_node(&mut v, "width", f32_vec_yaml(&widths, true));
-                            str_node(&mut v, "border-type", "image");
 
                             match details.source {
                                 NinePatchBorderSource::Image(image_key) => {
+                                    str_node(&mut v, "border-type", "image");
                                     if let Some(path) = self.path_for_image(image_key) {
                                         path_node(&mut v, "image", &path);
                                     }
                                 }
+                                NinePatchBorderSource::Gradient(gradient) => {
+                                    str_node(&mut v, "gradient", "image");
+                                    point_node(&mut v, "start", &gradient.start_point);
+                                    point_node(&mut v, "end", &gradient.end_point);
+                                    let mut stops = vec![];
+                                    for stop in display_list.get(base.gradient_stops()) {
+                                        stops.push(Yaml::Real(stop.offset.to_string()));
+                                        stops.push(Yaml::String(color_to_string(stop.color)));
+                                    }
+                                    yaml_node(&mut v, "stops", Yaml::Array(stops));
+                                    bool_node(&mut v, "repeat", gradient.extend_mode == ExtendMode::Repeat);
+                                }
+                                NinePatchBorderSource::RadialGradient(gradient) => {
+                                    str_node(&mut v, "border-type", "radial-gradient");
+                                    radial_gradient_to_yaml(
+                                        &mut v,
+                                        &gradient,
+                                        base.gradient_stops(),
+                                        display_list
+                                    );
+                                }
                             }
 
                             u32_node(&mut v, "image-width", details.width);
@@ -924,59 +945,6 @@ impl YamlFrameWriter {
                                 RepeatMode::Space => str_node(&mut v, "repeat-vertical", "space"),
                             };
                         }
-                        BorderDetails::Gradient(ref details) => {
-                            let widths: Vec<f32> = vec![
-                                item.widths.top,
-                                item.widths.right,
-                                item.widths.bottom,
-                                item.widths.left,
-                            ];
-                            let outset: Vec<f32> = vec![
-                                details.outset.top,
-                                details.outset.right,
-                                details.outset.bottom,
-                                details.outset.left,
-                            ];
-                            yaml_node(&mut v, "width", f32_vec_yaml(&widths, true));
-                            str_node(&mut v, "border-type", "gradient");
-                            point_node(&mut v, "start", &details.gradient.start_point);
-                            point_node(&mut v, "end", &details.gradient.end_point);
-                            let mut stops = vec![];
-                            for stop in display_list.get(base.gradient_stops()) {
-                                stops.push(Yaml::Real(stop.offset.to_string()));
-                                stops.push(Yaml::String(color_to_string(stop.color)));
-                            }
-                            yaml_node(&mut v, "stops", Yaml::Array(stops));
-                            bool_node(
-                                &mut v,
-                                "repeat",
-                                details.gradient.extend_mode == ExtendMode::Repeat,
-                            );
-                            yaml_node(&mut v, "outset", f32_vec_yaml(&outset, true));
-                        }
-                        BorderDetails::RadialGradient(ref details) => {
-                            let widths: Vec<f32> = vec![
-                                item.widths.top,
-                                item.widths.right,
-                                item.widths.bottom,
-                                item.widths.left,
-                            ];
-                            let outset: Vec<f32> = vec![
-                                details.outset.top,
-                                details.outset.right,
-                                details.outset.bottom,
-                                details.outset.left,
-                            ];
-                            yaml_node(&mut v, "width", f32_vec_yaml(&widths, true));
-                            str_node(&mut v, "border-type", "radial-gradient");
-                            yaml_node(&mut v, "outset", f32_vec_yaml(&outset, true));
-                            radial_gradient_to_yaml(
-                                &mut v,
-                                &details.gradient,
-                                base.gradient_stops(),
-                                display_list
-                            );
-                        }
                     }
                 }
                 BoxShadow(item) => {