rostests/dibtests/alphablend/alphablend.c

   1 #include <windows.h>
   2 #include <string.h>
   3
   4 BOOL WINAPI GdiAlphaBlend(HDC hdcDst, int xDst, int yDst, int widthDst, int heightDst,
   5                           HDC hdcSrc, int xSrc, int ySrc, int widthSrc, int heightSrc,
   6                            BLENDFUNCTION blendFunction);
   7
   8 #ifndef AC_SRC_ALPHA
   9 #define AC_SRC_ALPHA    (0x1)
  10 #endif
  11
  12 HINSTANCE HInst;
  13 const char* WndClassName = "GMainWnd";
  14 LRESULT CALLBACK MainWndProc(HWND HWnd, UINT Msg, WPARAM WParam,
  15    LPARAM LParam);
  16
  17 int APIENTRY WinMain(HINSTANCE HInstance, HINSTANCE HPrevInstance,
  18     LPTSTR lpCmdLine, int nCmdShow)
  19 {
  20    WNDCLASS wc;
  21    MSG msg;
  22
  23    HInst = HInstance;
  24
  25    memset(&wc, 0, sizeof(WNDCLASS));
  26
  27    wc.style = CS_VREDRAW | CS_HREDRAW | CS_DBLCLKS;
  28    wc.lpfnWndProc = MainWndProc;
  29    wc.hInstance = HInstance;
  30    wc.hCursor = LoadCursor(NULL, (LPCTSTR)IDC_ARROW);
  31   /* wc.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_BTNFACE + 1); */
  32    wc.hbrBackground = (HBRUSH)(COLOR_BTNFACE + 1);
  33    wc.lpszClassName = WndClassName;
  34
  35    if (RegisterClass(&wc))
  36    {
  37       HWND HWnd =
  38          CreateWindow(
  39             WndClassName, TEXT("AlphaBlend Rendering Demo"),
  40             WS_OVERLAPPED | WS_SYSMENU | WS_CAPTION |
  41             WS_VISIBLE | WS_CLIPSIBLINGS,
  42             0, 0, 320, 430,
  43             NULL, NULL, HInst, NULL
  44             );
  45
  46       if (HWnd)
  47       {
  48          ShowWindow(HWnd, nCmdShow);
  49          UpdateWindow(HWnd);
  50
  51          while (GetMessage(&msg, NULL, 0, 0))
  52          {
  53              TranslateMessage(&msg);
  54              DispatchMessage(&msg);
  55          }
  56       }
  57     }
  58     return 0;
  59 }
  60
  61 /* image related */
  62 BITMAP bmp;
  63 LPCSTR filename = TEXT("lena.bmp");
  64 HDC HMemDC = NULL, HMemDC2 = NULL;
  65 HBITMAP HOldBmp = NULL;
  66 PVOID pBmpBits = NULL;
  67 HBITMAP H32BppBitmap = NULL;
  68 BITMAPINFO bmpi;
  69
  70 BOOL ConvertBitmapTo32Bpp(HDC hDC, BITMAP *bmp)
  71 {
  72   ZeroMemory(&bmpi, sizeof(BITMAPINFO));
  73   bmpi.bmiHeader.biSize = sizeof(BITMAPINFO);
  74   bmpi.bmiHeader.biWidth = bmp->bmWidth;
  75   bmpi.bmiHeader.biHeight = bmp->bmHeight;
  76   bmpi.bmiHeader.biPlanes = 1;
  77   bmpi.bmiHeader.biBitCount = 32;
  78   bmpi.bmiHeader.biCompression = BI_RGB;
  79   bmpi.bmiHeader.biSizeImage = 4 * bmpi.bmiHeader.biWidth * bmpi.bmiHeader.biHeight;
  80   H32BppBitmap = CreateDIBSection(hDC, &bmpi, DIB_RGB_COLORS, &pBmpBits, 0, 0);
  81   if(H32BppBitmap)
  82   {
  83     HBITMAP bmpalpha;
  84     SelectObject(hDC, H32BppBitmap);
  85     BitBlt(hDC, 0, 0, bmp->bmWidth, bmp->bmHeight, HMemDC, 0, 0, SRCCOPY);
  86
  87     /* load and apply alpha channel */
  88     bmpalpha = LoadImage(HInst, MAKEINTRESOURCE(2000), IMAGE_BITMAP,
  89                             0, 0, 0);
  90     if(bmpalpha)
  91     {
  92       COLORREF *col = pBmpBits;
  93       int x, y;
  94       HDC hdcTemp = CreateCompatibleDC(NULL);
  95       if(!hdcTemp)
  96       {
  97         DeleteObject(bmpalpha);
  98         return FALSE;
  99       }
 100       SelectObject(hdcTemp, bmpalpha);
 101
 102       for(y = 0; y < bmp->bmHeight; y++)
 103       {
 104         for(x = 0; x < bmp->bmWidth; x++)
 105         {
 106           COLORREF Color = (COLORREF)GetRValue(GetPixel(hdcTemp, x, y)) << 24;
 107           *col++ |= Color;
 108         }
 109       }
 110
 111       DeleteObject(bmpalpha);
 112       DeleteDC(hdcTemp);
 113       return TRUE;
 114     }
 115     return FALSE;
 116   }
 117   return FALSE;
 118 }
 119
 120 LRESULT CALLBACK MainWndProc(HWND HWnd, UINT Msg, WPARAM WParam,
 121    LPARAM LParam)
 122 {
 123    switch (Msg)
 124    {
 125       case WM_CREATE:
 126       {
 127          /* create a memory DC */
 128          HMemDC = CreateCompatibleDC(NULL);
 129          if (HMemDC)
 130          {
 131             /* load a bitmap from file */
 132             HBITMAP HBmp =
 133                /* static_cast<HBITMAP> */(
 134                   LoadImage(HInst, MAKEINTRESOURCE(1000), IMAGE_BITMAP,
 135                             0, 0, 0)
 136                             );
 137             if (HBmp)
 138             {
 139                /* extract dimensions of the bitmap */
 140                GetObject(HBmp, sizeof(BITMAP), &bmp);
 141
 142                /* associate the bitmap with the memory DC */
 143                /* HOldBmp = static_cast<HBITMAP> */
 144                 (SelectObject(HMemDC, HBmp)
 145                   );
 146                 HMemDC2 = CreateCompatibleDC(NULL);
 147                 if(!ConvertBitmapTo32Bpp(HMemDC2, &bmp))
 148                 {
 149                   PostQuitMessage(0);
 150                   return 0;
 151                 }
 152             }
 153          }
 154       }
 155       case WM_PAINT:
 156       {
 157          PAINTSTRUCT ps;
 158          BLENDFUNCTION BlendFunc;
 159          HDC Hdc = BeginPaint(HWnd, &ps);
 160 #if 0
 161          try
 162 #endif
 163          {
 164
 165             BlendFunc.BlendOp = AC_SRC_OVER;
 166             BlendFunc.BlendFlags = 0;
 167             BlendFunc.SourceConstantAlpha = 128;
 168             BlendFunc.AlphaFormat = 0;
 169
 170             BitBlt(Hdc, 100, 90,
 171                    bmp.bmWidth, bmp.bmHeight,
 172                    HMemDC2, 0, 0,
 173                    SRCCOPY);
 174             GdiAlphaBlend(Hdc, 0, 0, bmp.bmWidth, bmp.bmHeight,
 175                           HMemDC2, 0, 0, bmp.bmWidth, bmp.bmHeight,
 176                           BlendFunc);
 177             GdiAlphaBlend(Hdc, bmp.bmWidth - 15, 10, bmp.bmWidth / 2, bmp.bmHeight / 2,
 178                           HMemDC2, 0, 0, bmp.bmWidth, bmp.bmHeight,
 179                           BlendFunc);
 180
 181             BlendFunc.SourceConstantAlpha = 255;
 182             BlendFunc.AlphaFormat = AC_SRC_ALPHA;
 183
 184             GdiAlphaBlend(Hdc, 140, 200, bmp.bmWidth, bmp.bmHeight,
 185                           HMemDC2, 0, 0, bmp.bmWidth, bmp.bmHeight,
 186                           BlendFunc);
 187             GdiAlphaBlend(Hdc, 20, 210, (bmp.bmWidth / 3) * 2, (bmp.bmHeight / 3) * 2,
 188                           HMemDC2, 0, 0, bmp.bmWidth, bmp.bmHeight,
 189                           BlendFunc);
 190          }
 191 #if 0
 192          catch (...)
 193          {
 194             EndPaint(HWnd, &ps);
 195          }
 196 #endif
 197          EndPaint(HWnd, &ps);
 198          break;
 199       }
 200       case WM_DESTROY:
 201       {
 202          /* clean up */
 203          DeleteObject(SelectObject(HMemDC, HOldBmp));
 204          DeleteDC(HMemDC);
 205          DeleteDC(HMemDC2);
 206
 207          PostQuitMessage(0);
 208          return 0;
 209       }
 210    }
 211    return DefWindowProc(HWnd, Msg, WParam, LParam);
 212 }