/**
 * @module cpixelformat_BGR555
 * @author Guenther Neuwirth (0626638), Manuel Mausz (0728348)
 * @brief  Implementation of CPixelFormat handling BGR555 color (real color)
 *         Windows Bitmaps.
 * @date   18.04.2009
 */

#include <boost/numeric/conversion/cast.hpp>
#include "cpixelformat_bgr555.h"

using namespace std;

void CPixelFormat_BGR555::setPixel(const uint32_t *pixel, uint32_t x, uint32_t y)
{
  /*
   * pixel[0] ... red
   * pixel[1] ... green
   * pixel[2] ... blue
   */

  if (m_bitmap->getPixelData() == NULL)
    throw PixelFormatError("No pixelbuffer allocated.");

  /* calc rowsize - boundary is 32 */
  uint32_t rowsize = 4 * static_cast<uint32_t>(
    ((CPixelFormat_BGR555::getBitCount() * abs(m_bitmap->getInfoHeader().biWidth)) + 31) / 32
  );

  /* if height is positive the y-coordinates are mirrored */
  if (m_bitmap->getInfoHeader().biHeight > 0)
    y = m_bitmap->getInfoHeader().biHeight - y - 1;
  uint32_t offset = y * rowsize + x * (4 * getBitCount() / 32);

  /* boundary check */
  if (offset + getBitCount()/8 > m_bitmap->getInfoHeader().biSizeImage)
    throw PixelFormatError("Pixel position is out of range.");

  /* convert color values to correct types */
  uint8_t *o = m_bitmap->getPixelData() + offset;
  *(uint16_t *)o = (uint16_t)(((pixel[2] << BGR555_BLUE_SHIFT)  & BGR555_BLUE_MASK)  |
                              ((pixel[1] << BGR555_GREEN_SHIFT) & BGR555_GREEN_MASK) |
                              ((pixel[0] << BGR555_RED_SHIFT)   & BGR555_RED_MASK));
}

/* vim: set et sw=2 ts=2: */