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    myfree(line);
  }
  
  return 1;
}

/*
=item i_box_cfill(im, x1, y1, x2, y2, fill)

=category Drawing
=synopsis i_box_cfill(im, 0, 0, im->xsize-1, im->ysize-1, fill);

Fills the box from (x1,y1) to (x2,y2) inclusive with fill.

=cut
*/

void
i_box_cfill(i_img *im,i_img_dim x1,i_img_dim y1,i_img_dim x2,i_img_dim y2,i_fill_t *fill) {
  i_render r;
  dIMCTXim(im);

  im_log((aIMCTX,1,"i_box_cfill(im* %p, p1(" i_DFp "), p2(" i_DFp "), fill %p)\n",
	  im, i_DFcp(x1, y1), i_DFcp(x2,y2), fill));

  ++x2;
  if (x1 < 0)
    x1 = 0;
  if (y1 < 0) 
    y1 = 0;
  if (x2 > im->xsize) 
    x2 = im->xsize;
  if (y2 >= im->ysize)
    y2 = im->ysize-1;
  if (x1 >= x2 || y1 > y2)
    return;

  i_render_init(&r, im, x2-x1);
  while (y1 <= y2) {
    i_render_fill(&r, x1, y1, x2-x1, NULL, fill);
    ++y1;
  }
  i_render_done(&r);
}

/* 
=item i_line(C<im>, C<x1>, C<y1>, C<x2>, C<y2>, C<color>, C<endp>)

=category Drawing

=for stopwords Bresenham's

Draw a line to image using Bresenham's line drawing algorithm

   im    - image to draw to
   x1    - starting x coordinate
   y1    - starting x coordinate
   x2    - starting x coordinate
   y2    - starting x coordinate
   color - color to write to image
   endp  - endpoint flag (boolean)

=cut
*/

void
i_line(i_img *im, i_img_dim x1, i_img_dim y1, i_img_dim x2, i_img_dim y2, const i_color *val, int endp) {
  i_img_dim x, y;
  i_img_dim dx, dy;
  i_img_dim p;

  dx = x2 - x1;
  dy = y2 - y1;


  /* choose variable to iterate on */
  if (i_abs(dx) > i_abs(dy)) {
    i_img_dim dx2, dy2, cpy;

    /* sort by x */
    if (x1 > x2) {
      i_img_dim t;
      t = x1; x1 = x2; x2 = t;
      t = y1; y1 = y2; y2 = t;
    }
    
    dx = i_abs(dx);
    dx2 = dx*2;
    dy = y2 - y1;

    if (dy<0) {
      dy = -dy;
      cpy = -1;
    } else {
      cpy = 1;
    }
    dy2 = dy*2;
    p = dy2 - dx;

    
    y = y1;
    for(x=x1; x<x2-1; x++) {
      if (p<0) {
        p += dy2;
      } else {
        y += cpy;
        p += dy2-dx2;
      }
      i_ppix(im, x+1, y, val);
    }
  } else {
    i_img_dim dy2, dx2, cpx;

    /* sort bx y */
    if (y1 > y2) {
      i_img_dim t;
      t = x1; x1 = x2; x2 = t;
      t = y1; y1 = y2; y2 = t;
    }
    
    dy = i_abs(dy);