Stronger synchronization for resize on osmesa.

We need to synchronize resize with when the renderer thinks that the resize occurs. This patch get's rid of display artifacts when resizing window on http://webkit.org/blog-files/3d-transforms/poster-circle.html when running with --use-gl=osmesa on linux.

BUG=none
TEST=see description


Review URL: http://codereview.chromium.org/9212058

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@119082 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 78 insertions, 142 deletions

diff --git a/ui/gfx/gl/gl_surface_linux.cc b/ui/gfx/gl/gl_surface_linux.cc
index 5f764fc..a6771d9 100644
--- a/ui/gfx/gl/gl_surface_linux.cc
+++ b/ui/gfx/gl/gl_surface_linux.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -36,19 +36,16 @@ class NativeViewGLSurfaceOSMesa : public GLSurfaceOSMesa {
 
   static bool InitializeOneOff();
 
-  // Initializes the GL context.
-  bool Initialize();
-
   // Implement a subset of GLSurface.
-  virtual void Destroy();
-  virtual bool IsOffscreen();
-  virtual bool SwapBuffers();
-  virtual std::string GetExtensions();
-  virtual bool PostSubBuffer(int x, int y, int width, int height);
+  virtual bool Initialize() OVERRIDE;
+  virtual void Destroy() OVERRIDE;
+  virtual bool Resize(const gfx::Size& new_size) OVERRIDE;
+  virtual bool IsOffscreen() OVERRIDE;
+  virtual bool SwapBuffers() OVERRIDE;
+  virtual std::string GetExtensions() OVERRIDE;
+  virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
 
  private:
-  bool UpdateSize();
-
   GC window_graphics_context_;
   gfx::PluginWindowHandle window_;
   GC pixmap_graphics_context_;
@@ -92,7 +89,7 @@ bool GLSurface::InitializeOneOffInternal() {
 
 NativeViewGLSurfaceOSMesa::NativeViewGLSurfaceOSMesa(
     gfx::PluginWindowHandle window)
-  : GLSurfaceOSMesa(OSMESA_BGRA, gfx::Size()),
+  : GLSurfaceOSMesa(OSMESA_BGRA, gfx::Size(1, 1)),
     window_graphics_context_(0),
     window_(window),
     pixmap_graphics_context_(0),
@@ -133,8 +130,6 @@ bool NativeViewGLSurfaceOSMesa::Initialize() {
     return false;
   }
 
-  UpdateSize();
-
   return true;
 }
 
@@ -155,18 +150,52 @@ void NativeViewGLSurfaceOSMesa::Destroy() {
   }
 }
 
+bool NativeViewGLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
+  if (!GLSurfaceOSMesa::Resize(new_size))
+    return false;
+
+  XWindowAttributes attributes;
+  if (!XGetWindowAttributes(g_osmesa_display, window_, &attributes)) {
+    LOG(ERROR) << "XGetWindowAttributes failed for window " << window_ << ".";
+    return false;
+  }
+
+  // Destroy the previous pixmap and graphics context.
+  if (pixmap_graphics_context_) {
+    XFreeGC(g_osmesa_display, pixmap_graphics_context_);
+    pixmap_graphics_context_ = NULL;
+  }
+  if (pixmap_) {
+    XFreePixmap(g_osmesa_display, pixmap_);
+    pixmap_ = 0;
+  }
+
+  // Recreate a pixmap to hold the frame.
+  pixmap_ = XCreatePixmap(g_osmesa_display,
+                          window_,
+                          new_size.width(),
+                          new_size.height(),
+                          attributes.depth);
+  if (!pixmap_) {
+    LOG(ERROR) << "XCreatePixmap failed.";
+    return false;
+  }
+
+  // Recreate a graphics context for the pixmap.
+  pixmap_graphics_context_ = XCreateGC(g_osmesa_display, pixmap_, 0, NULL);
+  if (!pixmap_graphics_context_) {
+    LOG(ERROR) << "XCreateGC failed";
+    return false;
+  }
+
+  return true;
+}
+
 bool NativeViewGLSurfaceOSMesa::IsOffscreen() {
   return false;
 }
 
 bool NativeViewGLSurfaceOSMesa::SwapBuffers() {
-  // Update the size before blitting so that the blit size is exactly the same
-  // as the window.
-  if (!UpdateSize()) {
-    LOG(ERROR) << "Failed to update size of GLContextOSMesa.";
-    return false;
-  }
-
   gfx::Size size = GetSize();
 
   XWindowAttributes attributes;
@@ -206,13 +235,6 @@ std::string NativeViewGLSurfaceOSMesa::GetExtensions() {
 
 bool NativeViewGLSurfaceOSMesa::PostSubBuffer(
     int x, int y, int width, int height) {
-  // Update the size before blitting so that the blit size is exactly the same
-  // as the window.
-  if (!UpdateSize()) {
-    LOG(ERROR) << "Failed to update size of GLContextOSMesa.";
-    return false;
-  }
-
   gfx::Size size = GetSize();
 
   // Move (0,0) from lower-left to upper-left
@@ -250,55 +272,6 @@ bool NativeViewGLSurfaceOSMesa::PostSubBuffer(
   return true;
 }
 
-bool NativeViewGLSurfaceOSMesa::UpdateSize() {
-  // Get the window size.
-  XWindowAttributes attributes;
-  if (!XGetWindowAttributes(g_osmesa_display, window_, &attributes)) {
-    LOG(ERROR) << "XGetWindowAttributes failed for window " << window_ << ".";
-    return false;
-  }
-  gfx::Size window_size = gfx::Size(std::max(1, attributes.width),
-                                    std::max(1, attributes.height));
-
-  // Early out if the size has not changed.
-  gfx::Size osmesa_size = GetSize();
-  if (pixmap_graphics_context_ && pixmap_ && window_size == osmesa_size)
-    return true;
-
-  // Change osmesa surface size to that of window.
-  Resize(window_size);
-
-  // Destroy the previous pixmap and graphics context.
-  if (pixmap_graphics_context_) {
-    XFreeGC(g_osmesa_display, pixmap_graphics_context_);
-    pixmap_graphics_context_ = NULL;
-  }
-  if (pixmap_) {
-    XFreePixmap(g_osmesa_display, pixmap_);
-    pixmap_ = 0;
-  }
-
-  // Recreate a pixmap to hold the frame.
-  pixmap_ = XCreatePixmap(g_osmesa_display,
-                          window_,
-                          window_size.width(),
-                          window_size.height(),
-                          attributes.depth);
-  if (!pixmap_) {
-    LOG(ERROR) << "XCreatePixmap failed.";
-    return false;
-  }
-
-  // Recreate a graphics context for the pixmap.
-  pixmap_graphics_context_ = XCreateGC(g_osmesa_display, pixmap_, 0, NULL);
-  if (!pixmap_graphics_context_) {
-    LOG(ERROR) << "XCreateGC failed";
-    return false;
-  }
-
-  return true;
-}
-
 #endif //  !USE_WAYLAND
 
 scoped_refptr<GLSurface> GLSurface::CreateViewGLSurface(
diff --git a/ui/gfx/gl/gl_surface_osmesa.cc b/ui/gfx/gl/gl_surface_osmesa.cc
index a6d4b4c..eea7ee4 100644
--- a/ui/gfx/gl/gl_surface_osmesa.cc
+++ b/ui/gfx/gl/gl_surface_osmesa.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -18,10 +18,15 @@ GLSurfaceOSMesa::~GLSurfaceOSMesa() {
   Destroy();
 }
 
-bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
-  if (new_size == size_)
-    return true;
+bool GLSurfaceOSMesa::Initialize() {
+  return Resize(size_);
+}
 
+void GLSurfaceOSMesa::Destroy() {
+  buffer_.reset();
+}
+
+bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
   GLContext* current_context = GLContext::GetCurrent();
   bool was_current = current_context && current_context->IsCurrent(this);
   if (was_current)
@@ -31,14 +36,17 @@ bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
   scoped_array<int32> old_buffer(buffer_.release());
 
   // Allocate a new one.
-  AllocateBuffer(new_size);
+  buffer_.reset(new int32[new_size.GetArea()]);
+  memset(buffer_.get(), 0, new_size.GetArea() * sizeof(buffer_[0]));
 
   // Copy the old back buffer into the new buffer.
-  int copy_width = std::min(size_.width(), new_size.width());
-  int copy_height = std::min(size_.height(), new_size.height());
-  for (int y = 0; y < copy_height; ++y) {
-    for (int x = 0; x < copy_width; ++x) {
-      buffer_[y * new_size.width() + x] = old_buffer[y * size_.width() + x];
+  if (old_buffer.get()) {
+    int copy_width = std::min(size_.width(), new_size.width());
+    int copy_height = std::min(size_.height(), new_size.height());
+    for (int y = 0; y < copy_height; ++y) {
+      for (int x = 0; x < copy_width; ++x) {
+        buffer_[y * new_size.width() + x] = old_buffer[y * size_.width() + x];
+      }
     }
   }
 
@@ -50,15 +58,6 @@ bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
   return true;
 }
 
-bool GLSurfaceOSMesa::Initialize() {
-  AllocateBuffer(size_);
-  return true;
-}
-
-void GLSurfaceOSMesa::Destroy() {
-  buffer_.reset();
-}
-
 bool GLSurfaceOSMesa::IsOffscreen() {
   return true;
 }
@@ -80,9 +79,4 @@ unsigned GLSurfaceOSMesa::GetFormat() {
   return format_;
 }
 
-void GLSurfaceOSMesa::AllocateBuffer(const Size& size) {
-  buffer_.reset(new int32[size.GetArea()]);
-  memset(buffer_.get(), 0, size.GetArea() * sizeof(buffer_[0]));
-}
-
 }  // namespace gfx
diff --git a/ui/gfx/gl/gl_surface_osmesa.h b/ui/gfx/gl/gl_surface_osmesa.h
index 2e0d384..9404050 100644
--- a/ui/gfx/gl/gl_surface_osmesa.h
+++ b/ui/gfx/gl/gl_surface_osmesa.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -20,13 +20,10 @@ class GL_EXPORT GLSurfaceOSMesa : public GLSurface {
   GLSurfaceOSMesa(unsigned format, const gfx::Size& size);
   virtual ~GLSurfaceOSMesa();
 
-  // Resize the back buffer, preserving the old content. Does nothing if the
-  // size is unchanged.
-  virtual bool Resize(const gfx::Size& new_size) OVERRIDE;
-
   // Implement GLSurface.
   virtual bool Initialize() OVERRIDE;
   virtual void Destroy() OVERRIDE;
+  virtual bool Resize(const gfx::Size& new_size) OVERRIDE;
   virtual bool IsOffscreen() OVERRIDE;
   virtual bool SwapBuffers() OVERRIDE;
   virtual gfx::Size GetSize() OVERRIDE;
@@ -34,8 +31,6 @@ class GL_EXPORT GLSurfaceOSMesa : public GLSurface {
   virtual unsigned GetFormat() OVERRIDE;
 
  private:
-  void AllocateBuffer(const Size& size);
-
   unsigned format_;
   gfx::Size size_;
   scoped_array<int32> buffer_;
diff --git a/ui/gfx/gl/gl_surface_win.cc b/ui/gfx/gl/gl_surface_win.cc
index 08b3396..4df75a9 100644
--- a/ui/gfx/gl/gl_surface_win.cc
+++ b/ui/gfx/gl/gl_surface_win.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -23,19 +23,15 @@ class NativeViewGLSurfaceOSMesa : public GLSurfaceOSMesa {
   explicit NativeViewGLSurfaceOSMesa(gfx::PluginWindowHandle window);
   virtual ~NativeViewGLSurfaceOSMesa();
 
-  // Initializes the GL context.
-  bool Initialize();
-
   // Implement subset of GLSurface.
-  virtual void Destroy();
-  virtual bool IsOffscreen();
-  virtual bool SwapBuffers();
-  virtual std::string GetExtensions();
-  virtual bool PostSubBuffer(int x, int y, int width, int height);
+  virtual bool Initialize() OVERRIDE;
+  virtual void Destroy() OVERRIDE;
+  virtual bool IsOffscreen() OVERRIDE;
+  virtual bool SwapBuffers() OVERRIDE;
+  virtual std::string GetExtensions() OVERRIDE;
+  virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
 
  private:
-  void UpdateSize();
-
   gfx::PluginWindowHandle window_;
   HDC device_context_;
 
@@ -64,7 +60,7 @@ bool GLSurface::InitializeOneOffInternal() {
 
 NativeViewGLSurfaceOSMesa::NativeViewGLSurfaceOSMesa(
     gfx::PluginWindowHandle window)
-  : GLSurfaceOSMesa(OSMESA_RGBA, gfx::Size()),
+  : GLSurfaceOSMesa(OSMESA_RGBA, gfx::Size(1, 1)),
     window_(window),
     device_context_(NULL) {
   DCHECK(window);
@@ -79,7 +75,6 @@ bool NativeViewGLSurfaceOSMesa::Initialize() {
     return false;
 
   device_context_ = GetDC(window_);
-  UpdateSize();
   return true;
 }
 
@@ -99,10 +94,6 @@ bool NativeViewGLSurfaceOSMesa::IsOffscreen() {
 bool NativeViewGLSurfaceOSMesa::SwapBuffers() {
   DCHECK(device_context_);
 
-  // Update the size before blitting so that the blit size is exactly the same
-  // as the window.
-  UpdateSize();
-
   gfx::Size size = GetSize();
 
   // Note: negating the height below causes GDI to treat the bitmap data as row
@@ -147,10 +138,6 @@ bool NativeViewGLSurfaceOSMesa::PostSubBuffer(
     int x, int y, int width, int height) {
   DCHECK(device_context_);
 
-  // Update the size before blitting so that the blit size is exactly the same
-  // as the window.
-  UpdateSize();
-
   gfx::Size size = GetSize();
 
   // Note: negating the height below causes GDI to treat the bitmap data as row
@@ -184,19 +171,6 @@ bool NativeViewGLSurfaceOSMesa::PostSubBuffer(
   return true;
 }
 
-void NativeViewGLSurfaceOSMesa::UpdateSize() {
-  // Change back buffer size to that of window. If window handle is invalid, do
-  // not change the back buffer size.
-  RECT rect;
-  if (!GetClientRect(window_, &rect))
-    return;
-
-  gfx::Size window_size = gfx::Size(
-    std::max(1, static_cast<int>(rect.right - rect.left)),
-    std::max(1, static_cast<int>(rect.bottom - rect.top)));
-  Resize(window_size);
-}
-
 scoped_refptr<GLSurface> GLSurface::CreateViewGLSurface(
     bool software,
     gfx::PluginWindowHandle window) {