Changed the signature of Application::Draw to accept elapsed time. It will be...

gpu/demos/app_framework/application.cc

 // Copyright (c) 2006-2009 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 "gpu/demos/app_framework/application.h"
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 #include "gpu/command_buffer/client/gles2_lib.h"
 #include "gpu/command_buffer/service/command_buffer_service.h"
 #include "gpu/command_buffer/service/gpu_processor.h"
@@ skipping 56 matching lines @@
       if (msg.message == WM_QUIT) done = true;
       TranslateMessage(&msg);
       DispatchMessage(&msg);
     }
     // Message queue is empty and application has not quit yet - keep painting.
     if (!done) SendMessage(window_handle_, WM_PAINT, 0, 0);
   }
 }
 
 void Application::OnPaint() {
-  Draw();
+  float elapsed_sec = 0.0f;
+  const base::Time current_time = base::Time::Now();
+  if (!last_draw_time_.is_null()) {
+    base::TimeDelta time_delta = current_time - last_draw_time_;
+    elapsed_sec = static_cast<float>(time_delta.InSecondsF());
+  }
+  last_draw_time_ = current_time;
+
+  Draw(elapsed_sec);
   gles2::GetGLContext()->SwapBuffers();
 }
 
 bool Application::InitRenderContext() {
   window_handle_ = CreateNativeWindow();
   if (window_handle_ == NULL) {
     return false;
   }
 
   scoped_ptr<CommandBufferService> command_buffer(new CommandBufferService);
@@ skipping 64 matching lines @@
 
   ShowWindow(hwnd, SW_SHOWNORMAL);
   // Set this to the GWL_USERDATA so that it is available to WindowProc.
   SetWindowLongPtr(hwnd, GWL_USERDATA, (LONG_PTR)this);
 
   return hwnd;
 }
 
 }  // namespace gpu_demos
 #endif  // defined(OS_WIN)