<?php
/*
 *    changed : 23. may. 03
 *    author  : hide@address.com
 *    download: http://www.phpclasses.org/
 *
 *    description :
 *        this class allows you to create and output bmp-images without
 *        the use of external modules (like GDlib or Imagemagick)
 *        since the bmp-format is really large (not optimized in any way),
 *        it's a rather slow way to deal with images.
 *        if anyone have the time for it, a dump to gif would be much
 *        appreciated.
 *
 *    disclaimer :
 *        this piece of code is freely usable by anyone. if it makes your life better,
 *        remember me in your eveningprayer. if it makes your life worse, try doing it any
 *        better yourself.
 */
class bmp_image {
	var $data;
	var $colors;
	var $width;
	var $height;

	function bmp_image($height, $width, $col=0)
	{
		$this->height = $height;
		$this->width = $width;
		$this->colors = array();
		for ($i=0;$i<256;$i++)
			array_push($this->colors, bmp_image::col_from_rgb(255,255-round($i/2),255-$i));

		$this->data = array();
		for ($n=0;$n<$height;$n++) {
			array_push($this->data, array_pad(array(), $width, $col));
		}
	}

	function plot($x, $y, $col)
	{
		$this->data[$y][$x] = $col;
	}

	function line($x, $y, $x1 ,$y1, $col=1)
	{
		$cc = $x;
		$cr = $y;
		$c  = $x1;
		$r = $y1;
		$dc = 0;$dr = 0;$sc = 0;$sr = 0;$i = 0;$e = 0;

		$dc=abs($c-$cc);
		$dr=abs($r-$cr);
		$sc=$dc==0?0:($c-$cc)/$dc;
		$sr=$dr==0?0:($r-$cr)/$dr;
		if ($dc>$dr) {
			$e=2*$dr-$dc;
			for($i=1; $i<=$dc; $i++) {
				$this->plot($cr, $cc, $col);
				if($e>=0) {
					$cr+=$sr;
					$e+=-2*$dc;
				}
				$cc+=$sc;
				$e+=2*$dr;
			}
		} else {
			$e=2*$dc-$dr;
			for($i=1; $i<=$dr; $i++) {
			$this->plot($cr, $cc, $col);
			if($e>=0) {
				$cc+=$sc;
				$e+=-2*$dr;
			}
			$cr+=$sr;
			$e+=2*$dc;
			}
		}
	}

	function bmp_dump($filename='image.bmp', $output=true)
	{
		$size = ($this->width*$this->height*3)+54;

		if ($output) {
			header('Content-Type: image/bmp');
			header('Pragma: no-cache');
			header('Content-Length: '.$size);
			header('Content-Disposition: inline; filename='.$filename);
		}

		// Bitmap File Header
		$ret = 'BM';			// header (2b)
		$ret .= bmp_image::int_to_dword($size);	// size of file (4b)
		$ret .= bmp_image::int_to_dword(0);	// reserved (4b)
		$ret .= bmp_image::int_to_dword(54);	// byte location in the file which is first byte of IMAGE (4b)
		// Bitmap Info Header
		$ret .= bmp_image::int_to_dword(40);	// Size of BITMAPINFOHEADER (4b)
		$ret .= bmp_image::int_to_dword($this->width);	// width of bitmap (4b)
		$ret .= bmp_image::int_to_dword($this->height);	// height of bitmap (4b)
		$ret .= bmp_image::int_to_word(1);	// biPlanes = 1 (2b)
		$ret .= bmp_image::int_to_word(24);	// biBitCount = {1 (mono) or 4 (16 clr ) or 8 (256 clr) or 24 (16 Mil)} (2b)
		$ret .= bmp_image::int_to_dword(0);	// RLE COMPRESSION (4b)
		$ret .= bmp_image::int_to_dword(0);	// width x height (4b)
		$ret .= bmp_image::int_to_dword(0);	// biXPelsPerMeter (4b)
		$ret .= bmp_image::int_to_dword(0);	// biYPelsPerMeter (4b)
		$ret .= bmp_image::int_to_dword(0);	// Number of palettes used (4b)
		$ret .= bmp_image::int_to_dword(0);	// Number of important colour (4b)
		// image data
		for ($x=count($this->data)-1;$x>=0;$x--) {
			for ($y=0;$y<count($this->data[$x]);$y++) {
				$ret .= $this->colors[$this->data[$x][$y]];
			}
		}
		if ($output) {
			echo $ret;
			return null;
		} else
			return $ret;
	}

	function int_to_dword($n)
	{
		return chr($n & 255).chr(($n >> 8) & 255).chr(($n >> 16) & 255).chr(($n >> 24) & 255);
	}
	function int_to_word($n)
	{
		return chr($n & 255).chr(($n >> 8) & 255);
	}

	function col_from_rgb($r,$g,$b)
	{
		return chr($b).chr($g).chr($r);
	}
}
?>