Function floodfill

src/doc/algorithm/floodfill.cpp:342–422

floodfill: * Fills an enclosed area (starting at point x, y) with the specified color. */

 *  Fills an enclosed area (starting at point x, y) with the specified color.
 */
void floodfill(const Image* image,
               const Mask* mask,
               int x, int y,
               const gfx::Rect& bounds,
               int tolerance, bool contiguous,
               void* data,
               AlgoHLine proc)
{
  // Make sure we have a valid starting point
  if ((x < 0) || (x >= image->width()) ||
      (y < 0) || (y >= image->height()))
    return;

  // What color to replace?
  color_t src_color = get_pixel(image, x, y);

  // Non-contiguous case, we replace colors in the whole image.
  if (!contiguous) {
    switch (image->pixelFormat()) {
      case IMAGE_RGB:
        replace_color<RgbTraits>(image, bounds, src_color, tolerance, data, proc);
        break;
      case IMAGE_GRAYSCALE:
        replace_color<GrayscaleTraits>(image, bounds, src_color, tolerance, data, proc);
        break;
      case IMAGE_INDEXED:
        replace_color<IndexedTraits>(image, bounds, src_color, tolerance, data, proc);
        break;
    }
    return;
  }

  /* set up the list of flooded segments */
  flood_buf.resize(image->height());
  flood_count = image->height();
  FLOODED_LINE* p = (FLOODED_LINE*)&flood_buf[0];
  for (int c=0; c<flood_count; c++) {
    p[c].flags = 0;
    p[c].lpos = SHRT_MAX;
    p[c].rpos = SHRT_MIN;
    p[c].y = y;
    p[c].next = 0;
  }

  // Start up the flood algorithm
  flooder(image, mask, x, y, bounds, src_color, tolerance, data, proc);

  // Continue as long as there are some segments still to test
  bool done;
  do {
    done = true;

    // For each line on the screen
    for (int c=0; c<flood_count; c++) {

      p = FLOOD_LINE(c);

      // Check below the segment?