Break glScheduleCALayerCHROMIUM into smaller functions.

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 6c45faae237d0a9c487f800282684d3e7b7b6c2b..219cda3cd04af44dd8f42f76ea346fecf055528e 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -2286,6 +2286,16 @@ class GLES2DecoderImpl : public GLES2Decoder, public ErrorStateClient {
 
   SamplerState default_sampler_state_;
 
+  struct CALayerSharedState{
+    float opacity;
+    bool is_clipped;
+    gfx::Rect clip_rect;
+    int sorting_context_id;
+    gfx::Transform transform;
+  };
+
+  std::unique_ptr<CALayerSharedState> ca_layer_shared_state_;
+
   DISALLOW_COPY_AND_ASSIGN(GLES2DecoderImpl);
 };
 
@@ -10733,6 +10743,32 @@ error::Error GLES2DecoderImpl::HandleScheduleOverlayPlaneCHROMIUM(
   return error::kNoError;
 }
 
+error::Error GLES2DecoderImpl::HandleScheduleCALayerSharedStateCHROMIUM(
+    uint32_t immediate_data_size,
+    const void* cmd_data) {
+  const gles2::cmds::ScheduleCALayerSharedStateCHROMIUM& c =
+      *static_cast<const gles2::cmds::ScheduleCALayerSharedStateCHROMIUM*>(
+          cmd_data);
+
+  const GLfloat* mem = GetSharedMemoryAs<const GLfloat*>(c.shm_id, c.shm_offset,
+                                                         20 * sizeof(GLfloat));
+  if (!mem) {
+    return error::kOutOfBounds;
+  }
+  gfx::RectF clip_rect(mem[0], mem[1], mem[2], mem[3]);
+  gfx::Transform transform(mem[4], mem[8], mem[12], mem[16],
+                           mem[5], mem[9], mem[13], mem[17],
+                           mem[6], mem[10], mem[14], mem[18],
+                           mem[7], mem[11], mem[15], mem[19]);
+  ca_layer_shared_state_.reset(new CALayerSharedState);
+  ca_layer_shared_state_->opacity = c.opacity;
+  ca_layer_shared_state_->is_clipped = c.is_clipped ? true : false;
+  ca_layer_shared_state_->clip_rect = gfx::ToEnclosingRect(clip_rect);
+  ca_layer_shared_state_->sorting_context_id = c.sorting_context_id;
+  ca_layer_shared_state_->transform = transform;
+  return error::kNoError;
+}
+
 error::Error GLES2DecoderImpl::HandleScheduleCALayerCHROMIUM(
     uint32_t immediate_data_size,
     const void* cmd_data) {
@@ -10745,6 +10781,13 @@ error::Error GLES2DecoderImpl::HandleScheduleCALayerCHROMIUM(
     return error::kNoError;
   }
 
+  if (!ca_layer_shared_state_) {
+    LOCAL_SET_GL_ERROR(
+        GL_INVALID_VALUE, "glScheduleCALayerCHROMIUM",

[piman, 2016/07/19 20:56:46]

nit: commonly GL_INVALID_OPERATION is the error raised when there is a state
inconsistency between multiple calls.

Either way, could you mention this in the extension text?

[erikchen, 2016/07/19 21:40:21]

Done.

+        "glScheduleCALayerSharedStateCHROMIUM has not been called");
+    return error::kNoError;
+  }
+
   gl::GLImage* image = nullptr;
   GLuint contents_texture_id = c.contents_texture_id;
   if (contents_texture_id) {
@@ -10765,23 +10808,19 @@ error::Error GLES2DecoderImpl::HandleScheduleCALayerCHROMIUM(
   }
 
   const GLfloat* mem = GetSharedMemoryAs<const GLfloat*>(c.shm_id, c.shm_offset,
-                                                         28 * sizeof(GLfloat));
+                                                         8 * sizeof(GLfloat));
   if (!mem) {
     return error::kOutOfBounds;
   }
   gfx::RectF contents_rect(mem[0], mem[1], mem[2], mem[3]);
   gfx::RectF bounds_rect(mem[4], mem[5], mem[6], mem[7]);
-  gfx::RectF clip_rect(mem[8], mem[9], mem[10], mem[11]);
-  gfx::Transform transform(mem[12], mem[16], mem[20], mem[24],
-                           mem[13], mem[17], mem[21], mem[25],
-                           mem[14], mem[18], mem[22], mem[26],
-                           mem[15], mem[19], mem[23], mem[27]);
 
   ui::CARendererLayerParams params = ui::CARendererLayerParams(
-      c.is_clipped ? true : false, gfx::ToEnclosingRect(clip_rect),
-      c.sorting_context_id, transform, image, contents_rect,
+      ca_layer_shared_state_->is_clipped, ca_layer_shared_state_->clip_rect,
+      ca_layer_shared_state_->sorting_context_id,
+      ca_layer_shared_state_->transform, image, contents_rect,
       gfx::ToEnclosingRect(bounds_rect), c.background_color, c.edge_aa_mask,
-      c.opacity, filter);
+      ca_layer_shared_state_->opacity, filter);
   if (!surface_->ScheduleCALayer(params)) {
     LOCAL_SET_GL_ERROR(GL_INVALID_OPERATION, "glScheduleCALayerCHROMIUM",
                        "failed to schedule CALayer");
@@ -13711,6 +13750,10 @@ void GLES2DecoderImpl::DoSwapBuffers() {
         is_offscreen ? offscreen_size_ : surface_->GetSize());
   }
 
+  // The GL_CHROMIUM_schedule_ca_layer requires that SwapBuffers resets shared
+  // state here.
+  ca_layer_shared_state_.reset();

[piman, 2016/07/19 20:56:46]

nit: can you also add this to HandlePostSubBufferCHROMIUM and
DoCommitOverlayPlanes?

[erikchen, 2016/07/19 21:40:21]

Done.

+
   // If offscreen then don't actually SwapBuffers to the display. Just copy
   // the rendered frame to another frame buffer.
   if (is_offscreen) {