FiveTech Support Forums

void TransBmp( HBITMAP hBitmap, int iXsize, int iYsize,
               COLORREF rgbTransparent, HDC hDC,
               int iXOffset, int iYOffset, int iWidth, int iHeight )
{
  HDC mDC, nDC;
  HBITMAP hMask, hBmOld1, hBmOld2;

  mDC = CreateCompatibleDC( hDC );
  
  if( mDC )
  {
    hBmOld1 = ( HBITMAP ) SelectObject( mDC, hBitmap );

    hMask = CreateBitmap( iXsize, iYsize, 1, 1, NULL );
    
    if( hMask )
    {
       nDC = CreateCompatibleDC( hDC );
        
       if( nDC )
       {
          hBmOld2 = ( HBITMAP ) SelectObject( nDC, hMask );
          SetBkColor( mDC, rgbTransparent );

          BitBlt( nDC, 0, 0, iXsize, iYsize, mDC, 0, 0, SRCCOPY );

          SetStretchBltMode( hDC, COLORONCOLOR );

          StretchBlt( hDC, iXOffset, iYOffset, iWidth, iHeight,
                      mDC, 0, 0, iXsize, iYsize,
                      SRCINVERT );

          StretchBlt( hDC, iXOffset, iYOffset, iWidth, iHeight,
                      nDC, 0, 0, iXsize, iYsize,
                      SRCAND );

          StretchBlt( hDC, iXOffset, iYOffset, iWidth, iHeight,
                      mDC, 0, 0, iXsize, iYsize,
                      SRCINVERT );

          SelectObject( nDC, hBmOld2 );
          DeleteDC( nDC );
        }
        DeleteObject( hMask );
    }
    SelectObject( mDC, hBmOld1 );
    DeleteDC( mDC );
  }
}