1 files changed, 137 insertions, 0 deletions
diff --git a/gfx/wr/webrender/res/gpu_cache.glsl b/gfx/wr/webrender/res/gpu_cache.glsl
new file mode 100644
index 0000000000..cd5e41fec4
--- /dev/null
+++ b/gfx/wr/webrender/res/gpu_cache.glsl
@@ -0,0 +1,137 @@
+/* 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/. */
+
+uniform HIGHP_SAMPLER_FLOAT sampler2D sGpuCache;
+
+#define VECS_PER_IMAGE_RESOURCE     2
+
+// TODO(gw): This is here temporarily while we have
+//           both GPU store and cache. When the GPU
+//           store code is removed, we can change the
+//           PrimitiveInstance instance structure to
+//           use 2x unsigned shorts as vertex attributes
+//           instead of an int, and encode the UV directly
+//           in the vertices.
+ivec2 get_gpu_cache_uv(HIGHP_FS_ADDRESS int address) {
+    return ivec2(uint(address) % WR_MAX_VERTEX_TEXTURE_WIDTH,
+                 uint(address) / WR_MAX_VERTEX_TEXTURE_WIDTH);
+}
+
+vec4[2] fetch_from_gpu_cache_2_direct(ivec2 address) {
+    return vec4[2](
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(1, 0))
+    );
+}
+
+vec4[2] fetch_from_gpu_cache_2(HIGHP_FS_ADDRESS int address) {
+    ivec2 uv = get_gpu_cache_uv(address);
+    return vec4[2](
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(1, 0))
+    );
+}
+
+vec4 fetch_from_gpu_cache_1_direct(ivec2 address) {
+    return texelFetch(sGpuCache, address, 0);
+}
+
+vec4 fetch_from_gpu_cache_1(HIGHP_FS_ADDRESS int address) {
+    ivec2 uv = get_gpu_cache_uv(address);
+    return texelFetch(sGpuCache, uv, 0);
+}
+
+#ifdef WR_VERTEX_SHADER
+
+vec4[8] fetch_from_gpu_cache_8(int address) {
+    ivec2 uv = get_gpu_cache_uv(address);
+    return vec4[8](
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(1, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(2, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(3, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(4, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(5, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(6, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(7, 0))
+    );
+}
+
+vec4[3] fetch_from_gpu_cache_3(int address) {
+    ivec2 uv = get_gpu_cache_uv(address);
+    return vec4[3](
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(1, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(2, 0))
+    );
+}
+
+vec4[3] fetch_from_gpu_cache_3_direct(ivec2 address) {
+    return vec4[3](
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(1, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(2, 0))
+    );
+}
+
+vec4[4] fetch_from_gpu_cache_4_direct(ivec2 address) {
+    return vec4[4](
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(1, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(2, 0)),
+        TEXEL_FETCH(sGpuCache, address, 0, ivec2(3, 0))
+    );
+}
+
+vec4[4] fetch_from_gpu_cache_4(int address) {
+    ivec2 uv = get_gpu_cache_uv(address);
+    return vec4[4](
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(1, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(2, 0)),
+        TEXEL_FETCH(sGpuCache, uv, 0, ivec2(3, 0))
+    );
+}
+
+//TODO: image resource is too specific for this module
+
+struct ImageSource {
+    RectWithEndpoint uv_rect;
+    vec4 user_data;
+};
+
+ImageSource fetch_image_source(int address) {
+    //Note: number of blocks has to match `renderer::BLOCKS_PER_UV_RECT`
+    vec4 data[2] = fetch_from_gpu_cache_2(address);
+    RectWithEndpoint uv_rect = RectWithEndpoint(data[0].xy, data[0].zw);
+    return ImageSource(uv_rect, data[1]);
+}
+
+ImageSource fetch_image_source_direct(ivec2 address) {
+    vec4 data[2] = fetch_from_gpu_cache_2_direct(address);
+    RectWithEndpoint uv_rect = RectWithEndpoint(data[0].xy, data[0].zw);
+    return ImageSource(uv_rect, data[1]);
+}
+
+// Fetch optional extra data for a texture cache resource. This can contain
+// a polygon defining a UV rect within the texture cache resource.
+// Note: the polygon coordinates are in homogeneous space.
+struct ImageSourceExtra {
+    vec4 st_tl;
+    vec4 st_tr;
+    vec4 st_bl;
+    vec4 st_br;
+};
+
+ImageSourceExtra fetch_image_source_extra(int address) {
+    vec4 data[4] = fetch_from_gpu_cache_4(address + VECS_PER_IMAGE_RESOURCE);
+    return ImageSourceExtra(
+        data[0],
+        data[1],
+        data[2],
+        data[3]
+    );
+}
+
+#endif //WR_VERTEX_SHADER