bitmap 리전 만들기..

#define _WIN32_WINNT 0x0501
#define WINVER 0x0501

#include <windows.h>
#include "resource.h" // <<-- 추가

// BitmapToRegion : Create a region from the "non-transparent" pixels of a bitma
// Author :  Jean-Edouard Lachand-Robert (http://www.geocities.com/Paris/LeftBank/1160/resume.htm), June 1998
//
// hBmp :   Source bitma
// cTransparentColor : Color base for the "transparent" pixels (default is black
// cTolerance :  Color tolerance for the "transparent" pixels
//
// A pixel is assumed to be transparent if the value of each of its 3 components (blue, green and red) is
// greater or equal to the corresponding value in cTransparentColor and is lower or equal to the
// corresponding value in cTransparentColor + cTolerance

HRGN BitmapToRegion (HBITMAP hBmp, COLORREF cTransparentColor, COLORREF cTolerance)
{
 HRGN hRgn = NULL;

 if (hBmp)
 {
  // Create a memory DC inside which we will scan the bitmap content
  HDC hMemDC = ::CreateCompatibleDC(NULL);
  if (hMemDC)
  {
   // Get bitmap size
   BITMAP bm;
   ::GetObject(hBmp, sizeof(bm), &bm);

   // Create a 32 bits depth bitmap and select it into the memory DC
   BITMAPINFOHEADER RGB32BITSBITMAPINFO = {
     sizeof(BITMAPINFOHEADER), // biSize
     bm.bmWidth,     // biWidth;
     bm.bmHeight,    // biHeight;
     1,       // biPlanes;
     32,       // biBitCount
     BI_RGB,      // biCompression;
     0,       // biSizeImage;
     0,       // biXPelsPerMeter;
     0,       // biYPelsPerMeter;
     0,       // biClrUsed;
     0       // biClrImportant;
   };
   VOID * pbits32;
   HBITMAP hbm32 = ::CreateDIBSection(hMemDC, (BITMAPINFO *)&RGB32BITSBITMAPINFO, DIB_RGB_COLORS, &pbits32, NULL, 0);
   if (hbm32)
   {
    HBITMAP holdBmp = (HBITMAP)::SelectObject(hMemDC, hbm32);

    // Create a DC just to copy the bitmap into the memory DC
    HDC hDC = ::CreateCompatibleDC(hMemDC);
    if (hDC)
    {
     // Get how many bytes per row we have for the bitmap bits (rounded up to 32 bits)
     BITMAP bm32;
     ::GetObject(hbm32, sizeof(bm32), &bm32);
     while (bm32.bmWidthBytes % 4)
      bm32.bmWidthBytes++;

     // Copy the bitmap into the memory DC
     HBITMAP holdBmp = (HBITMAP)::SelectObject(hDC, hBmp);
     ::BitBlt(hMemDC, 0, 0, bm.bmWidth, bm.bmHeight, hDC, 0, 0, SRCCOPY);

     // For better performances, we will use the ExtCreateRegion() function to create the
     // region. This function take a RGNDATA structure on entry. We will add rectangles by
     // amount of ALLOC_UNIT number in this structure.
     #define ALLOC_UNIT 100
     DWORD maxRects = ALLOC_UNIT;
     HANDLE hData = ::GlobalAlloc(GMEM_MOVEABLE, sizeof(RGNDATAHEADER) + (sizeof(RECT) * maxRects));
     RGNDATA *pData = (RGNDATA *)::GlobalLock(hData);
     pData->rdh.dwSize = sizeof(RGNDATAHEADER);
     pData->rdh.iType = RDH_RECTANGLES;
     pData->rdh.nCount = pData->rdh.nRgnSize = 0;
     ::SetRect(&pData->rdh.rcBound, MAXLONG, MAXLONG, 0, 0);

     // Keep on hand highest and lowest values for the "transparent" pixels
     BYTE lr = GetRValue(cTransparentColor);
     BYTE lg = GetGValue(cTransparentColor);
     BYTE lb = GetBValue(cTransparentColor);
     BYTE hr = min(0xff, lr + GetRValue(cTolerance));
     BYTE hg = min(0xff, lg + GetGValue(cTolerance));
     BYTE hb = min(0xff, lb + GetBValue(cTolerance));

     // Scan each bitmap row from bottom to top (the bitmap is inverted vertically)
     BYTE *p32 = (BYTE *)bm32.bmBits + (bm32.bmHeight - 1) * bm32.bmWidthBytes;
     for (int y = 0; y < bm.bmHeight; y++)
     {
      // Scan each bitmap pixel from left to right
      for (int x = 0; x < bm.bmWidth; x++)
      {
       // Search for a continuous range of "non transparent pixels"
       int x0 = x;
       LONG *p = (LONG *)p32 + x;
       while (x < bm.bmWidth)
       {
        BYTE b = GetRValue(*p);
        if (b >= lr && b <= hr)
        {
         b = GetGValue(*p);
         if (b >= lg && b <= hg)
         {
          b = GetBValue(*p);
          if (b >= lb && b <= hb)
           // This pixel is "transparent"
           break;
         }
        }
        p++;
        x++;
       }

       if (x > x0)
       {
        // Add the pixels (x0, y) to (x, y+1) as a new rectangle in the region
        if (pData->rdh.nCount >= maxRects)
        {
         ::GlobalUnlock(hData);
         maxRects += ALLOC_UNIT;
         hData = ::GlobalReAlloc(hData, sizeof(RGNDATAHEADER) + (sizeof(RECT) * maxRects), GMEM_MOVEABLE);
         pData = (RGNDATA *)::GlobalLock(hData);
        }
        RECT *pr = (RECT *)&pData->Buffer;
        ::SetRect(&pr[pData->rdh.nCount], x0, y, x, y+1);
        if (x0 < pData->rdh.rcBound.left)
         pData->rdh.rcBound.left = x0;
        if (y < pData->rdh.rcBound.top)
         pData->rdh.rcBound.top = y;
        if (x > pData->rdh.rcBound.right)
         pData->rdh.rcBound.right = x;
        if (y+1 > pData->rdh.rcBound.bottom)
         pData->rdh.rcBound.bottom = y+1;
        pData->rdh.nCount++;

        // On Windows98, ExtCreateRegion() may fail if the number of rectangles is too
        // large (ie: > 4000). Therefore, we have to create the region by multiple steps.
        if (pData->rdh.nCount == 2000)
        {
         HRGN h = ::ExtCreateRegion(NULL, sizeof(RGNDATAHEADER) + (sizeof(RECT) * maxRects), pData);
         if (hRgn)
         {
          ::CombineRgn(hRgn, hRgn, h, RGN_OR);
          ::DeleteObject(h);
         }
         else
          hRgn = h;
         pData->rdh.nCount = 0;
         ::SetRect(&pData->rdh.rcBound, MAXLONG, MAXLONG, 0, 0);
        }
       }
      }

      // Go to next row (remember, the bitmap is inverted vertically)
      p32 -= bm32.bmWidthBytes;
     }

     // Create or extend the region with the remaining rectangles
     HRGN h = ::ExtCreateRegion(NULL, sizeof(RGNDATAHEADER) + (sizeof(RECT) * maxRects), pData);
     if (hRgn)
     {
      ::CombineRgn(hRgn, hRgn, h, RGN_OR);
      ::DeleteObject(h);
     }
     else
      hRgn = h;

     // Clean up
     ::GlobalFree(hData);
     ::SelectObject(hDC, holdBmp);
     ::DeleteDC(hDC);
    }

    ::DeleteObject(::SelectObject(hMemDC, holdBmp));
   }

   ::DeleteDC(hMemDC);
  } 
 }

 return hRgn;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
 static HBITMAP hBitmap = (HBITMAP)LoadBitmap( GetModuleHandle(0),
           MAKEINTRESOURCE(IDB_BITMAP1));

 switch(msg)
 {
 case WM_PAINT:
  {
   PAINTSTRUCT ps;
   HDC hdc = BeginPaint(hwnd, &ps);
 
   HDC mem = CreateCompatibleDC(hdc);
   HBITMAP old = (HBITMAP)SelectObject(mem, hBitmap);
   
   BitBlt( hdc, 0, 0, 413, 382, mem, 0, 0, SRCCOPY);
   SelectObject(mem, old);
   DeleteDC(mem);
   EndPaint(hwnd, &ps);
   
  }
  return 0;

 case WM_NCHITTEST : return HTCAPTION;

 case WM_CREATE :
  {
   // 비정형 윈도우는 대부분 캡션바와 size 조절을 때어 낸다.
   UINT style = GetWindowLong( hwnd, GWL_STYLE );

   style = style & ~WS_CAPTION & ~WS_THICKFRAME;

   SetWindowLong( hwnd, GWL_STYLE, style );
   //===============================================

   // 흑백 비트맵을 Load 한다.
   HBITMAP hMask = (HBITMAP)LoadBitmap( GetModuleHandle(0),  // hInstance
           MAKEINTRESOURCE(IDB_BITMAP2));
   // 비트맵으로 리젼을 만들어 낸다.
   HRGN h = BitmapToRegion( hMask, RGB(255,255,255), 0); // 2번째 인자부터, 3번째 인자 사이의 색깔을 투명하게

   SetWindowRgn( hwnd, h, TRUE );

   DeleteObject( h );
   DeleteObject( hMask);
  }
  return 0;

 case WM_DESTROY :
  DeleteObject( hBitmap ); // <<-- 추가 2

  PostQuitMessage(0);
  return 0;
 }
 return DefWindowProc(hwnd, msg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrev, LPSTR lpCmdLine, int nShowCmd)
{
 WNDCLASS wc;

 wc.cbClsExtra = 0;
 wc.cbWndExtra = 0;
 wc.hbrBackground = (HBRUSH)GetStockObject(GRAY_BRUSH);
 wc.hCursor = LoadCursor(0, IDC_ARROW);
 wc.hIcon = LoadIcon(0, IDI_APPLICATION);
 wc.hInstance = hInstance;
 wc.lpfnWndProc = WndProc;
 wc.lpszClassName = "클래스 이름";
 wc.lpszMenuName = 0;
 wc.style = 0;

 ATOM atom = RegisterClass(&wc);

 if(atom == 0)
 {
  MessageBox(0, "클래스 등록에 실패했습니다.", "에러", MB_OK);
  return 0;
 }

 HWND hwnd = CreateWindowEx(0, "클래스 이름", "윈도우창 이름", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 400, 400, 0, 0, hInstance, 0);

 ShowWindow(hwnd, nShowCmd);
 UpdateWindow(hwnd);

 MSG msg;

 while(GetMessage(&msg, 0, 0, 0))
 {
  TranslateMessage(&msg);
  DispatchMessage(&msg);
 }

 return 0;
}