During virtual context switches only restore texture units that have changed from the previous cont…

ui/gl/gl_state_restorer.h

Index: ui/gl/gl_state_restorer.h
diff --git a/ui/gl/gl_state_restorer.h b/ui/gl/gl_state_restorer.h
index 6d8791f3c16ac00c7e54ced91d7c1235cdf35f18..378a14931b03de54ef714ff046be09d5c4664810 100644
--- a/ui/gl/gl_state_restorer.h
+++ b/ui/gl/gl_state_restorer.h
@@ -8,6 +8,12 @@
 #include "base/basictypes.h"
 #include "ui/gl/gl_export.h"
 
+namespace gpu {
+namespace gles2 {
+class ContextState;
+}
+}
+
 namespace gfx {
 
 // An interface for Restoring GL State.
@@ -18,9 +24,10 @@ class GL_EXPORT GLStateRestorer {
   virtual ~GLStateRestorer();
 
   virtual bool IsInitialized() = 0;
-  virtual void RestoreState() = 0;
+  virtual void RestoreState(const gpu::gles2::ContextState* prev_state) = 0;
   virtual void RestoreAllTextureUnitBindings() = 0;
   virtual void RestoreFramebufferBindings() = 0;
+  virtual const gpu::gles2::ContextState* GetContextState() = 0;

[piman, 2014/01/13 22:12:46]

Mmh, this causes a dependency cycle gpu -> ui -> gpu

[kaanb, 2014/01/13 22:17:00]

It's only a forward declaration though. One alternative is using void* as the
type but that violates type safety and would require static_casts. wdyt?

[piman, 2014/01/13 22:37:47]

It would just make it worse (hiding the circular dependency, and as you mention,
violating the type safety).

Maybe what you want is to pass a GLStateRestorer to RestoreState, and do the
GetContextState dance (using internal APIs) in the implementation in the gpu/
code.

 
   DISALLOW_COPY_AND_ASSIGN(GLStateRestorer);
 };