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  1. /**
  2.  * @module CPixelFormat_Indexed8
  3.  * @author Guenther Neuwirth (0626638), Manuel Mausz (0728348)
  4.  * @brief  Implementation of CPixelFormat handling 24bit indexed bitmaps.
  5.  * @date   02.05.2009
  6.  */
  7.  
  8. #include <boost/numeric/conversion/cast.hpp>
  9. #include <assert.h>
  10. #include "cpixelformat_indexed8.h"
  11. #include "cbitmap.h"
  12.  
  13. using namespace std;
  14.  
  15. void CPixelFormat_Indexed8::getPixel(RGBPIXEL& pixel, uint32_t x, uint32_t y)
  16. {
  17.   if (m_bitmap->getPixelData() == NULL)
  18.     throw PixelFormatError("No pixelbuffer allocated.");
  19.   if (m_bitmap->getColorTable().size() == 0)
  20.     return;
  21.   assert(m_bitmap->getPixelDataSize() > 0);
  22.  
  23.   uint32_t offset = y * m_bitmap->getWidth() + x;
  24.  
  25.   /* boundary check */
  26.   if (offset * sizeof(uint32_t) + sizeof(uint32_t) > m_bitmap->getPixelDataSize())
  27.     throw PixelFormatError("Pixel position is out of range.");
  28.  
  29.   uint32_t color = *((uint32_t *)m_bitmap->getPixelData() + offset);
  30.  
  31.   map<uint32_t, RGBPIXEL *>::iterator it;
  32.   if ((it = m_bitmap->getColorTable().find(color)) == m_bitmap->getColorTable().end())
  33.     throw PixelFormatError("Pixel has no reference in colortable.");
  34.  
  35.   pixel.red   = (*it).second->red;
  36.   pixel.green = (*it).second->green;
  37.   pixel.blue  = (*it).second->blue;
  38. }
  39.  
  40. /*----------------------------------------------------------------------------*/
  41.  
  42. void CPixelFormat_Indexed8::setPixel(const RGBPIXEL& pixel, uint32_t x, uint32_t y)
  43. {
  44.   if (m_bitmap->getPixelData() == NULL)
  45.     throw PixelFormatError("No pixelbuffer allocated.");
  46.   /* if colortable is empty there are no pixels */
  47.   if (m_bitmap->getColorTable().size() == 0)
  48.     return;
  49.   assert(m_bitmap->getPixelDataSize() > 0);
  50.  
  51.   uint32_t offset = y * m_bitmap->getWidth() + x;
  52.  
  53.   /* boundary check */
  54.   if (offset * sizeof(uint32_t) + sizeof(uint32_t) > m_bitmap->getPixelDataSize())
  55.     throw PixelFormatError("Pixel position is out of range.");
  56.  
  57.   /* try to look up color in colortable */
  58.   map<uint32_t, RGBPIXEL *>::iterator it;
  59.   for(it = m_bitmap->getColorTable().begin(); it != m_bitmap->getColorTable().end(); it++)
  60.   {
  61.     if ((*it).second->red   == pixel.red &&
  62.         (*it).second->green == pixel.green &&
  63.         (*it).second->blue  == pixel.blue)
  64.       break;
  65.   }
  66.  
  67.   uint32_t index = (*it).first;
  68.   /* need to get a new entry for our color */
  69.   if (it == m_bitmap->getColorTable().end())
  70.   {
  71.     index = (*it).first + 1;
  72.     RGBPIXEL *pixelptr = new RGBPIXEL;
  73.     pixelptr->red   = pixel.red;
  74.     pixelptr->green = pixel.green;
  75.     pixelptr->blue  = pixel.blue;
  76.     m_bitmap->getColorTable()[ index ] = pixelptr;
  77.   }
  78.  
  79.   /* set color */
  80.   *((uint32_t *)m_bitmap->getPixelData() + offset) = index;
  81. }
  82.  
  83. /* vim: set et sw=2 ts=2: */
  84.