1 files changed, 23 insertions, 0 deletions
diff --git a/gfx/wr/webrender/res/gpu_buffer.glsl b/gfx/wr/webrender/res/gpu_buffer.glsl
new file mode 100644
index 0000000000..fa9ba6f318
--- /dev/null
+++ b/gfx/wr/webrender/res/gpu_buffer.glsl
@@ -0,0 +1,23 @@
+/* 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 sGpuBuffer;
+
+ivec2 get_gpu_buffer_uv(HIGHP_FS_ADDRESS int address) {
+    return ivec2(uint(address) % WR_MAX_VERTEX_TEXTURE_WIDTH,
+                 uint(address) / WR_MAX_VERTEX_TEXTURE_WIDTH);
+}
+
+vec4 fetch_from_gpu_buffer_1(HIGHP_FS_ADDRESS int address) {
+    ivec2 uv = get_gpu_buffer_uv(address);
+    return texelFetch(sGpuBuffer, uv, 0);
+}
+
+vec4[2] fetch_from_gpu_buffer_2(HIGHP_FS_ADDRESS int address) {
+    ivec2 uv = get_gpu_buffer_uv(address);
+    return vec4[2](
+        TEXEL_FETCH(sGpuBuffer, uv, 0, ivec2(0, 0)),
+        TEXEL_FETCH(sGpuBuffer, uv, 0, ivec2(1, 0))
+    );
+}