Create child window using WS_EX_NOPARENTNOTIFY for WGL.

ui/gl/gl_surface_wgl.cc

 // 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.
 
 #include "ui/gl/gl_surface_wgl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/gl/gl_bindings.h"
@@ skipping 81 matching lines @@
     intermediate_class.hCursor = LoadCursor(NULL, IDC_ARROW);
     intermediate_class.hbrBackground = NULL;
     intermediate_class.lpszMenuName = NULL;
     intermediate_class.lpszClassName = L"Intermediate GL Window";
     window_class_ = RegisterClass(&intermediate_class);
     if (!window_class_) {
       LOG(ERROR) << "RegisterClass failed.";
       return false;
     }
 
-    window_handle_ = CreateWindow(
-        reinterpret_cast<wchar_t*>(window_class_),
-        L"",
-        WS_OVERLAPPEDWINDOW,
-        0, 0,
-        100, 100,
-        NULL,
-        NULL,
-        NULL,
-        NULL);
+    window_handle_ = CreateWindowEx(WS_EX_NOPARENTNOTIFY,

[Ken Russell (switch to Gerrit), 2014/10/16 00:58:47]

Is WS_EX_NOPARENTNOTIFY strictly needed for this window, or just the child
window below?

+                                    reinterpret_cast<wchar_t*>(window_class_),
+                                    L"",
+                                    WS_OVERLAPPEDWINDOW,
+                                    0,
+                                    0,
+                                    100,
+                                    100,
+                                    NULL,
+                                    NULL,
+                                    NULL,
+                                    NULL);
     if (!window_handle_) {
       LOG(ERROR) << "CreateWindow failed.";
       return false;
     }
 
     device_context_ = GetDC(window_handle_);
     pixel_format_ = ChoosePixelFormat(device_context_,
                                       &kPixelFormatDescriptor);
     if (pixel_format_ == 0) {
       LOG(ERROR) << "Unable to get the pixel format for GL context.";
@@ skipping 46 matching lines @@
   g_display = wgl_display.release();
   initialized = true;
   return true;
 }
 
 HDC GLSurfaceWGL::GetDisplayDC() {
   return g_display->device_context();
 }
 
 NativeViewGLSurfaceWGL::NativeViewGLSurfaceWGL(gfx::AcceleratedWidget window)
-    : window_(window),
-      device_context_(NULL) {
+    : window_(window), child_window_(NULL), device_context_(NULL) {
   DCHECK(window);
 }
 
 NativeViewGLSurfaceWGL::~NativeViewGLSurfaceWGL() {
   Destroy();
 }
 
 bool NativeViewGLSurfaceWGL::Initialize() {
   DCHECK(!device_context_);
 
-  DWORD process_id;
-  GetWindowThreadProcessId(window_, &process_id);
-  if (process_id != GetCurrentProcessId()) {
-    LOG(ERROR) << "Can't use window created in " << process_id
-               << " with wgl in " << GetCurrentProcessId();
+  RECT rect;
+  if (!GetClientRect(window_, &rect)) {
+    LOG(ERROR) << "GetClientRect failed.\n";
     Destroy();
     return false;
   }
 
-  device_context_ = GetDC(window_);
+  // Create a child window. WGL has problems using a window handle owned by
+  // another process.
+  child_window_ =
+      CreateWindowEx(WS_EX_NOPARENTNOTIFY,
+                     reinterpret_cast<wchar_t*>(g_display->window_class()),
+                     L"",
+                     WS_CHILDWINDOW | WS_DISABLED | WS_VISIBLE,
+                     0,
+                     0,
+                     rect.right - rect.left,
+                     rect.bottom - rect.top,
+                     window_,
+                     NULL,
+                     NULL,
+                     NULL);
+  if (!child_window_) {
+    LOG(ERROR) << "CreateWindow failed.\n";
+    Destroy();
+    return false;
+  }
+
+  // The GL context will render to this window.
+  device_context_ = GetDC(child_window_);
   if (!device_context_) {
     LOG(ERROR) << "Unable to get device context for window.";
     Destroy();
     return false;
   }
 
   if (!SetPixelFormat(device_context_,
                       g_display->pixel_format(),
                       &kPixelFormatDescriptor)) {
     LOG(ERROR) << "Unable to set the pixel format for GL context.";
     Destroy();
     return false;
   }
 
   return true;
 }
 
 void NativeViewGLSurfaceWGL::Destroy() {
-  if (window_ && device_context_)
-    ReleaseDC(window_, device_context_);
+  if (child_window_ && device_context_)
+    ReleaseDC(child_window_, device_context_);
 
+  if (child_window_)
+    DestroyWindow(child_window_);
+
+  child_window_ = NULL;
   device_context_ = NULL;
 }
 
 bool NativeViewGLSurfaceWGL::IsOffscreen() {
   return false;
 }
 
 bool NativeViewGLSurfaceWGL::SwapBuffers() {
   TRACE_EVENT2("gpu", "NativeViewGLSurfaceWGL:RealSwapBuffers",
       "width", GetSize().width(),
       "height", GetSize().height());
 
+  // Resize the child window to match the parent before swapping. Do not repaint
+  // it as it moves.
+  RECT rect;
+  if (!GetClientRect(window_, &rect))
+    return false;
+  if (!MoveWindow(child_window_,
+                  0,
+                  0,
+                  rect.right - rect.left,
+                  rect.bottom - rect.top,
+                  FALSE)) {
+    return false;
+  }
+
   DCHECK(device_context_);
   return ::SwapBuffers(device_context_) == TRUE;
 }
 
 gfx::Size NativeViewGLSurfaceWGL::GetSize() {
   RECT rect;
-  BOOL result = GetClientRect(window_, &rect);
+  BOOL result = GetClientRect(child_window_, &rect);
   DCHECK(result);
   return gfx::Size(rect.right - rect.left, rect.bottom - rect.top);
 }
 
 void* NativeViewGLSurfaceWGL::GetHandle() {
   return device_context_;
 }
 
 PbufferGLSurfaceWGL::PbufferGLSurfaceWGL(const gfx::Size& size)
     : size_(size),
@@ skipping 63 matching lines @@
 
 gfx::Size PbufferGLSurfaceWGL::GetSize() {
   return size_;
 }
 
 void* PbufferGLSurfaceWGL::GetHandle() {
   return device_context_;
 }
 
 }  // namespace gfx