#include "windows.h"
  #include "d3d10.h"

  bool g_bContinue = true;

  //Besides the main function, there must be a message processing function
  LRESULT WINAPI MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam )
  {
      switch( msg )
      {
       case WM_DESTROY:
          PostQuitMessage( 0 );
          g_bContinue = false;
          return 0;
      }
      return DefWindowProc( hWnd, msg, wParam, lParam );
  }

  //The entry point of a windows application is the WinMain function
  INT WINAPI WinMain( HINSTANCE hInst, HINSTANCE, LPSTR, INT )
  {
      //Create a window class.
      WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, MsgProc, 0L, 0L, 
                        GetModuleHandle(NULL), NULL, NULL, NULL, NULL,
                        "Direct3D Window", NULL };
      //Register the window class.
      RegisterClassEx( &wc );
      //Create the application's window.
      HWND hWnd = CreateWindow( "Direct3D Window", "DirectX Wiki - D3D10 Tutorial 1", 
                                WS_OVERLAPPEDWINDOW, 100, 100, 400, 400,
                                GetDesktopWindow(), NULL, wc.hInstance, NULL );

      ShowWindow(hWnd,SW_SHOW);

      //Create the Direct3D Device and Swap Chain
      DXGI_SWAP_CHAIN_DESC sd;
      ZeroMemory( &sd, sizeof(sd) );
      sd.BufferCount = 1;
      sd.BufferDesc.Width = 640;
      sd.BufferDesc.Height = 480;
      sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
      sd.BufferDesc.RefreshRate.Numerator = 60;
      sd.BufferDesc.RefreshRate.Denominator = 1;
      sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
      sd.OutputWindow = hWnd;
      sd.SampleDesc.Count = 1;
      sd.SampleDesc.Quality = 0;
      sd.Windowed = TRUE;

      IDXGISwapChain* pSwapChain = NULL;
      ID3D10Device* pd3dDevice = NULL;
      if( FAILED( D3D10CreateDeviceAndSwapChain( NULL, 
                                               D3D10_DRIVER_TYPE_REFERENCE, 
                                               NULL,
                                               0,
                                               D3D10_SDK_VERSION, 
                                               &sd,
                                               &pSwapChain,
                                               &pd3dDevice ) ) )
      {
          return FALSE;
      }

      // Create a render target view(from Backbuffer)
      ID3D10Texture2D *pBackBuffer = NULL;
      ID3D10RenderTargetView *pRenderTargetView = NULL;
      if( FAILED( pSwapChain->GetBuffer( 0, __uuidof( ID3D10Texture2D ), (LPVOID*)&pBackBuffer ) ) )
          return FALSE;
      HRESULT hr = pd3dDevice->CreateRenderTargetView( pBackBuffer, NULL, &pRenderTargetView );
      pBackBuffer->Release();
      if( FAILED( hr ) )
          return FALSE;
      pd3dDevice->OMSetRenderTargets( 1, &pRenderTargetView, NULL );

      //In D3D10 this must be done, because there is no default Viewport
      D3D10_VIEWPORT vp;
      vp.Width = 640;
      vp.Height = 480;
      vp.MinDepth = 0.0f;
      vp.MaxDepth = 1.0f;
      vp.TopLeftX = 0;
      vp.TopLeftY = 0;
      pd3dDevice->RSSetViewports( 1, &vp );

      MSG msg; 
      while( g_bContinue )
      {
          //Clear render region with blue
          float ClearColor[4] = { 0.0f, 0.0f, 1.0f, 1.0f }; //red,green,blue,alpha
          pd3dDevice->ClearRenderTargetView( pRenderTargetView, ClearColor );
   
          pSwapChain->Present( 0, 0 );

          // A window has to handle its messages.
          TranslateMessage( &msg );
          DispatchMessage( &msg );
          PeekMessage(&msg, 0, 0, 0, PM_REMOVE);
      }
      
      //Do not forget to clean up here
      pSwapChain->Release();
      pSwapChain = NULL;
      pRenderTargetView->Release();
      pRenderTargetView = NULL;
      pd3dDevice->Release();
      pd3dDevice = NULL;

      return 0;
  }