Resize synchronization for Linux.

app/gfx/gl/gl_context.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef APP_GFX_GL_GL_CONTEXT_H_
 #define APP_GFX_GL_GL_CONTEXT_H_
 #pragma once
 
 #include <string>
 
+#include "base/callback.h"
+#include "base/basictypes.h"
+#include "base/scoped_ptr.h"
 #include "build/build_config.h"
 #include "gfx/native_widget_types.h"
 #include "gfx/size.h"
 
 namespace gfx {
 
 // Encapsulates an OpenGL context, hiding platform specific management.
 class GLContext {
  public:
   GLContext() {}
   virtual ~GLContext() {}
 
   // Destroys the GL context.
   virtual void Destroy() = 0;
 
   // Makes the GL context current on the current thread.
   virtual bool MakeCurrent() = 0;
 
   // Returns true if this context is current.
   virtual bool IsCurrent() = 0;
 
   // Returns true if this context is offscreen.
   virtual bool IsOffscreen() = 0;
 
   // Swaps front and back buffers. This has no effect for off-screen
   // contexts.
   virtual bool SwapBuffers() = 0;
 
-  // Set the size of the back buffer.
-  // FIXME(backer): Currently a NOP. Once we have an implementation for each
-  //     backend we can switch it to pure virtual.
-  virtual void SetSize(gfx::Size) {}
+  // Set the size of the back buffer. Calls the callback.

[nduca, 2010/11/23 16:59:49]

Is there a way to put this callback on the GL-specific implementation? Its a bit
awkward to have this on the global GL context.

[jonathan.backer, 2010/11/23 21:00:19]

Done.

+  virtual void SetSize(gfx::Size size);
+
+  // Sometimes used to delegate resizing the back buffer.
+  virtual void RegisterSetSizeCallback(Callback1<gfx::Size>::Type* callback);
 
   // Get the size of the back buffer.
   virtual gfx::Size GetSize() = 0;
 
   // Get the underlying platform specific GL context "handle".
   virtual void* GetHandle() = 0;
 
   // Set swap interval. This context must be current.
   virtual void SetSwapInterval(int interval) = 0;
 
@@ skipping 15 matching lines @@
   // Create a GL context used for offscreen rendering. It is initially backed by
   // a 1x1 pbuffer. Use it to create an FBO to do useful rendering.
   // |share_context|, if non-NULL, is a context which the internally created
   // OpenGL context shares textures and other resources.
   static GLContext* CreateOffscreenGLContext(GLContext* shared_context);
 
  protected:
   bool InitializeCommon();
 
  private:
+  scoped_ptr<Callback1<gfx::Size>::Type> set_size_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(GLContext);
 };
 
 }  // namespace gfx
 
 #endif  // APP_GFX_GL_GL_CONTEXT_H_