Bug 1579235 - Part 4 - Refactor more parts of brush yuv shader. r=nical

Move the UV writing function into the shared yuv.glsl include so
that the YUV compositing shader will be able to access it.

Differential Revision: https://phabricator.services.mozilla.com/D63815

--HG--
extra : moz-landing-system : lando

gfx/wr/webrender/res/brush_yuv_image.glsl

@@ -29,34 +29,6 @@ flat varying int vFormat;
 
 #ifdef WR_VERTEX_SHADER
 
-#ifdef WR_FEATURE_TEXTURE_RECT
-    #define TEX_SIZE(sampler) vec2(1.0)
-#else
-    #define TEX_SIZE(sampler) vec2(textureSize(sampler, 0).xy)
-#endif
-
-void write_uv_rect(
-    int resource_id,
-    vec2 f,
-    vec2 texture_size,
-    out vec3 uv,
-    out vec4 uv_bounds
-) {
-    ImageResource res = fetch_image_resource(resource_id);
-    vec2 uv0 = res.uv_rect.p0;
-    vec2 uv1 = res.uv_rect.p1;
-
-    uv.xy = mix(uv0, uv1, f);
-    uv.z = res.layer;
-
-    uv_bounds = vec4(uv0 + vec2(0.5), uv1 - vec2(0.5));
-
-    #ifndef WR_FEATURE_TEXTURE_RECT
-        uv.xy /= texture_size;
-        uv_bounds /= texture_size.xyxy;
-    #endif
-}
-
 struct YuvPrimitive {
     float coefficient;
     int color_space;
@@ -93,14 +65,20 @@ void yuv_brush_vs(
 #endif
 
     if (vFormat == YUV_FORMAT_PLANAR) {
-        write_uv_rect(prim_user_data.x, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
-        write_uv_rect(prim_user_data.y, f, TEX_SIZE(sColor1), vUv_U, vUvBounds_U);
-        write_uv_rect(prim_user_data.z, f, TEX_SIZE(sColor2), vUv_V, vUvBounds_V);
+        ImageResource res_y = fetch_image_resource(prim_user_data.x);
+        ImageResource res_u = fetch_image_resource(prim_user_data.y);
+        ImageResource res_v = fetch_image_resource(prim_user_data.z);
+        write_uv_rect(res_y.uv_rect.p0, res_y.uv_rect.p1, res_y.layer, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
+        write_uv_rect(res_u.uv_rect.p0, res_u.uv_rect.p1, res_u.layer, f, TEX_SIZE(sColor1), vUv_U, vUvBounds_U);
+        write_uv_rect(res_v.uv_rect.p0, res_v.uv_rect.p1, res_v.layer, f, TEX_SIZE(sColor2), vUv_V, vUvBounds_V);
     } else if (vFormat == YUV_FORMAT_NV12) {
-        write_uv_rect(prim_user_data.x, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
-        write_uv_rect(prim_user_data.y, f, TEX_SIZE(sColor1), vUv_U, vUvBounds_U);
+        ImageResource res_y = fetch_image_resource(prim_user_data.x);
+        ImageResource res_u = fetch_image_resource(prim_user_data.y);
+        write_uv_rect(res_y.uv_rect.p0, res_y.uv_rect.p1, res_y.layer, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
+        write_uv_rect(res_u.uv_rect.p0, res_u.uv_rect.p1, res_u.layer, f, TEX_SIZE(sColor1), vUv_U, vUvBounds_U);
     } else if (vFormat == YUV_FORMAT_INTERLEAVED) {
-        write_uv_rect(prim_user_data.x, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
+        ImageResource res_y = fetch_image_resource(prim_user_data.x);
+        write_uv_rect(res_y.uv_rect.p0, res_y.uv_rect.p1, res_y.layer, f, TEX_SIZE(sColor0), vUv_Y, vUvBounds_Y);
     }
 }
 #endif

gfx/wr/webrender/res/yuv.glsl

@@ -10,6 +10,12 @@
 
 #ifdef WR_VERTEX_SHADER
 
+#ifdef WR_FEATURE_TEXTURE_RECT
+    #define TEX_SIZE(sampler) vec2(1.0)
+#else
+    #define TEX_SIZE(sampler) vec2(textureSize(sampler, 0).xy)
+#endif
+
 #define YUV_COLOR_SPACE_REC601      0
 #define YUV_COLOR_SPACE_REC709      1
 #define YUV_COLOR_SPACE_REC2020     2
@@ -68,6 +74,26 @@ mat3 get_yuv_color_matrix(int color_space) {
             return YuvColorMatrixRec2020;
     }
 }
+
+void write_uv_rect(
+    vec2 uv0,
+    vec2 uv1,
+    float layer,
+    vec2 f,
+    vec2 texture_size,
+    out vec3 uv,
+    out vec4 uv_bounds
+) {
+    uv.xy = mix(uv0, uv1, f);
+    uv.z = layer;
+
+    uv_bounds = vec4(uv0 + vec2(0.5), uv1 - vec2(0.5));
+
+    #ifndef WR_FEATURE_TEXTURE_RECT
+        uv.xy /= texture_size;
+        uv_bounds /= texture_size.xyxy;
+    #endif
+}
 #endif
 
 #ifdef WR_FRAGMENT_SHADER