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Flood fill example in C

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This flood fill code is adapted from a Tetris clone called "Tetanus On Drugs" by Damian Yerrick. It's licensed under the GNU General Public License and comes with ABSOLUTELY NO WARRANTY.

  #define BOARD_WIDTH  10
  #define BOARD_HEIGHT 20

  typedef struct MAP
  {
    unsigned char b[BOARD_HEIGHT][BOARD_WIDTH];
  } MAP;

  static void flood_loop(MAP *map, int x, int y,
                         unsigned int dst_c, unsigned  int src_c)
  {
    int fillL, fillR, i;
    int in_line = 1;

    /* find left side, filling along the way */
    fillL = fillR = x;
    while( in_line )
    {
      map->b[y][fillL] = dst_c;
      fillL--;
      in_line = (fillL < 0) ? 0 : (map->b[y][fillL] == src_c);
    }
    fillL++;

    /* find right side, filling along the way */
    in_line = 1;
    while( in_line )
    {
      map->b[y][fillR] = c;
      fillR++;
      in_line = (fillR > 9) ? 0 : (map->b[y][fillR] == fillC);
    }
    fillR--;

    /* search top and bottom */
    for(i = fillL; i <= fillR; i++)
    {
      if( y > 0 && map->b[y - 1][i] == fillC )
flood_loop(map, i, y - 1, c, fillC);
      if( y < BOARD_HEIGHT && map->b[y + 1][i] == fillC )
flood_loop(map, i, y + 1, c, fillC);
    }
  }

  void flood_fill(MAP *map, int x, int y, unsigned int c)
  {
    flood_loop(map, x, y, c, map->b[y][x]);
    map->b[y][x] = c;  /* some buggy optimizers needed this line */
  }

This is the same algorithm modified for Java by Claudio Santana

  int checkPixel(int[] oldPix, int[] newPix)
  {
    return (newPix[0] == oldPix[0] &&
    newPix[1] == oldPix[1]	&&
    newPix[2] == oldPix[2]  &&
    newPix[3] == oldPix[3] ? 1:0);
  }

  void floodLoop(WritableRaster raster, int x, int y, int[] fill, int[] old)
  {
    int fillL, fillR,i;
    int in_line=1;
    int[] aux =	{255,255,255,255};

    // find left side, filling along the way
    fillL = fillR = x;
    while(in_line!=0)
    {
      int[] p = raster.getPixel(fillL,y,aux);
      raster.setPixel(fillL,y,fill);
      fillL--;
      in_line = (fillL < 0) ? 0 : checkPixel(raster.getPixel(fillL,y,aux),old);
    }
    fillL++;

    // find right side, filling along the way
    in_line = 1;
    while (in_line!=0)
    {
      raster.setPixel(fillR,y,fill);
      fillR++;
      in_line = (fillR > d.width-1) ? 0 : checkPixel(raster.getPixel(fillR,y,aux),old);
    }
    fillR--;

    // look up and down
    for( i=fillL; i<=fillR; i++ )
    {
      if ( y>0 && checkPixel(raster.getPixel(i,y-1,aux),old)!=0 )
        floodLoop(raster,i,y-1,fill,old);
      if ( y<d.height-1 && checkPixel(raster.getPixel(i,y+1,aux),old)!=0 )
        floodLoop(raster,i,y+1,fill,old);
    }

  }

  // Initial method you must call
  void floodLoop(WritableRaster raster, int x, int y, int[] fill)
  {
    int[] aux = new int[] {255,255,255,255};

    // validation so we don't fall in an infinite loop trying to
    // paint in the same color
    if ( checkPixel(raster.getPixel(x,y,aux),fill)!=0 )
      return;

    floodLoop(raster,x,y,fill,raster.getPixel(x,y,aux) );
  }



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