png.cpp

   1 /////////////////////////////////////////////////////////////////////////////////
   2 //
   3 // $Id: png.cpp,v 1.1 2002/06/29 15:03:33 nedko Exp $
   4 //
   5 // DESCRIPTION:
   6 //
   7 // NOTES:
   8 //
   9 /////////////////////////////////////////////////////////////////////////////////
  10
  11 #include "ph.h"
  12 #include "png.h"
  13
  14 #define NOT_LOADED_BITMAP_HEIGHT 50
  15 #define NOT_LOADED_BITMAP_WIDTH 300
  16
  17 CPNGImage::CPNGImage()
  18 {
  19   m_nWidth = 0;
  20   m_nHeight = 0;
  21   m_pData = NULL;
  22 }
  23
  24 CPNGImage::~CPNGImage()
  25 {
  26 }
  27
  28 void PNGAPI
  29 CPNGImage::PNG_ErrorHandler PNGARG((png_structp s, png_const_charp str))
  30 {
  31   ::MessageBox(NULL,str,"PNG Error",MB_OK);
  32 }
  33
  34 bool
  35 CPNGImage::LoadPNGImage(const char *pszPath)
  36 {
  37   png_structp png_ptr;
  38   png_infop info_ptr;
  39   unsigned int sig_read = 0;
  40
  41   FILE *fp = fopen(pszPath, "rb");
  42   if (!fp)
  43   {
  44     return false;
  45   }
  46
  47   png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
  48                                    NULL,
  49                                    PNG_ErrorHandler,
  50                                    PNG_ErrorHandler);
  51
  52   if (png_ptr == NULL)
  53   {
  54     fclose(fp);
  55     return false;
  56   }
  57
  58   info_ptr = png_create_info_struct(png_ptr);
  59   if (info_ptr == NULL)
  60   {
  61     fclose(fp);
  62     png_destroy_read_struct(&png_ptr, png_infopp_NULL, png_infopp_NULL);
  63     return false;
  64   }
  65
  66   if (setjmp(png_jmpbuf(png_ptr)))
  67   {
  68     /* Free all of the memory associated with the png_ptr and info_ptr */
  69     png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
  70     fclose(fp);
  71     /* If we get here, we had a problem reading the file */
  72     return false;
  73   }
  74
  75   png_init_io(png_ptr, fp);
  76
  77   /* If we have already read some of the signature */
  78   png_set_sig_bytes(png_ptr, sig_read);
  79
  80   png_read_png(png_ptr,
  81                info_ptr,
  82                PNG_TRANSFORM_IDENTITY,
  83                png_voidp_NULL);
  84
  85
  86   /* clean up after the read, and free any memory allocated - REQUIRED */
  87   png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
  88
  89   /* close the file */
  90   fclose(fp);
  91
  92   return true;
  93 }
  94
  95 unsigned int
  96 CPNGImage::GetWidth()
  97 {
  98   if (m_pData)
  99     return m_nWidth;
 100   else
 101     return NOT_LOADED_BITMAP_WIDTH;
 102 }
 103
 104 unsigned int
 105 CPNGImage::GetHeight()
 106 {
 107   if (m_pData)
 108     return m_nHeight;
 109   else
 110     return NOT_LOADED_BITMAP_HEIGHT;
 111 }
 112
 113 bool
 114 CPNGImage::SelectBitmap(HDC hMemoryDC)
 115 {
 116   BITMAPV4HEADER BIH;
 117   ZeroMemory(&BIH,sizeof(BIH));
 118   BIH.bV4Size = sizeof(BIH);
 119   unsigned int x,y;
 120   unsigned char *pPixel;
 121
 122   unsigned char *pInternalData = new unsigned char[327*45*4];
 123   for (y = 0 ; y < 45; y++)
 124   {
 125     pPixel= pInternalData + 327 * 4 * y;
 126
 127     for (x = 0 ; x < 327 ; x++)
 128     {
 129       pPixel[0]= 0xFF; // blue
 130       pPixel[1]= 0xFF; // green
 131       pPixel[2]= 0xFF; // red
 132       pPixel[3]= 180; // alpha
 133       pPixel+= 4;
 134     }
 135   }
 136
 137   HBITMAP hBitmap = CreateBitmap(NOT_LOADED_BITMAP_WIDTH,NOT_LOADED_BITMAP_HEIGHT,1,32,pInternalData);
 138
 139 //  delete pInternalData;
 140
 141   if (!hBitmap)
 142     return false;
 143
 144   if (!GetDIBits(hMemoryDC, hBitmap, 0, 0, NULL, (BITMAPINFO *)&BIH, DIB_RGB_COLORS))
 145     return false;
 146
 147   BIH.bV4RedMask   = 0x00FF0000;
 148   BIH.bV4GreenMask = 0x0000FF00;
 149   BIH.bV4BlueMask  = 0x000000FF;
 150   BIH.bV4AlphaMask = 0xFF000000;
 151
 152   unsigned char *pData = new unsigned char[BIH.bV4SizeImage];
 153   if (!GetDIBits(hMemoryDC, hBitmap, 0, BIH.bV4Height, pData, (BITMAPINFO *)&BIH, DIB_RGB_COLORS))
 154   {
 155     delete pData;
 156     return false;
 157   }
 158
 159   for (y = 0 ; y < BIH.bV4Height; y++)
 160   {
 161     pPixel= pData + BIH.bV4Width * 4 * y;
 162
 163     for (x = 0 ; x < BIH.bV4Width ; x++)
 164     {
 165       pPixel[0]= (unsigned __int8)(((unsigned int)pPixel[0])*pPixel[3]/255);
 166       pPixel[1]= (unsigned __int8)(((unsigned int)pPixel[1])*pPixel[3]/255);
 167       pPixel[2]= (unsigned __int8)(((unsigned int)pPixel[2])*pPixel[3]/255);
 168       pPixel+= 4;
 169     }
 170   }
 171
 172   if (!SetDIBits(hMemoryDC, hBitmap, 0, BIH.bV4Height, pData, (BITMAPINFO *)&BIH, DIB_RGB_COLORS))
 173   {
 174     delete pData;
 175     return false;
 176   }
 177
 178   delete pData;
 179
 180   SelectObject(hMemoryDC, hBitmap);
 181
 182   return true;
 183 }
 184
 185 /////////////////////////////////////////////////////////////////////////////////
 186 //
 187 // Modifications log:
 188 //
 189 // !!! WARNING !!! Following lines are automatically updated by the CVS system.
 190 //
 191 //   $Log: png.cpp,v $
 192 //   Revision 1.1  2002/06/29 15:03:33  nedko
 193 //   *** empty log message ***
 194 //
 195 /////////////////////////////////////////////////////////////////////////////////