gecko-dev/gfx/webrender/res/clip_shared.glsl

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GLSL

/* 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/. */
#include rect,clip_scroll,render_task,resource_cache,snap,transform
#ifdef WR_VERTEX_SHADER
#define SEGMENT_ALL 0
#define SEGMENT_CORNER_TL 1
#define SEGMENT_CORNER_TR 2
#define SEGMENT_CORNER_BL 3
#define SEGMENT_CORNER_BR 4
in int aClipRenderTaskAddress;
in int aScrollNodeId;
in int aClipSegment;
in ivec4 aClipDataResourceAddress;
struct ClipMaskInstance {
int render_task_address;
int scroll_node_id;
int segment;
ivec2 clip_data_address;
ivec2 resource_address;
};
ClipMaskInstance fetch_clip_item() {
ClipMaskInstance cmi;
cmi.render_task_address = aClipRenderTaskAddress;
cmi.scroll_node_id = aScrollNodeId;
cmi.segment = aClipSegment;
cmi.clip_data_address = aClipDataResourceAddress.xy;
cmi.resource_address = aClipDataResourceAddress.zw;
return cmi;
}
struct ClipVertexInfo {
vec3 local_pos;
vec2 screen_pos;
RectWithSize clipped_local_rect;
};
RectWithSize intersect_rect(RectWithSize a, RectWithSize b) {
vec4 p = clamp(vec4(a.p0, a.p0 + a.size), b.p0.xyxy, b.p0.xyxy + b.size.xyxy);
return RectWithSize(p.xy, max(vec2(0.0), p.zw - p.xy));
}
// 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,
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) {
vec4 snap_positions = compute_snap_positions(
scroll_node.transform,
local_clip_rect
);
vec2 snap_offsets = compute_snap_offset_impl(
device_pos,
scroll_node.transform,
local_clip_rect,
RectWithSize(snap_positions.xy, snap_positions.zw - snap_positions.xy),
snap_positions
);
actual_pos -= snap_offsets;
}
vec4 node_pos;
// Select the local position, based on whether we are rasterizing this
// clip mask in local- or sccreen-space.
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);
}
// compute the point position inside the scroll node, in CSS space
vec2 vertex_pos = device_pos +
area.common_data.task_rect.p0 -
area.screen_origin;
gl_Position = uTransform * vec4(vertex_pos, 0.0, 1);
init_transform_vs(vec4(local_clip_rect.p0, local_clip_rect.p0 + local_clip_rect.size));
ClipVertexInfo vi = ClipVertexInfo(node_pos.xyw, actual_pos, local_clip_rect);
return vi;
}
#endif //WR_VERTEX_SHADER
#ifdef WR_FRAGMENT_SHADER
//Note: identical to prim_shared
float distance_to_line(vec2 p0, vec2 perp_dir, vec2 p) {
vec2 dir_to_p0 = p0 - p;
return dot(normalize(perp_dir), dir_to_p0);
}
#endif //WR_FRAGMENT_SHADER