how can i make chess like pattern image using gd library

[neovantage]

Hey geeks,
i want to draw a jpeg image of pattern chess.
I can draw solid color image using gd libraray and here is my code

//$t_im having image path, $t_wt,$t_ht is specified width and height respectively.
$blue = imagecolorallocate($t_im,149,0,0);
imagefilledrectangle($t_im,0,0,$t_wt,$t_ht,$blue);

But i want to draw image like a chess have pattern. Please find the attahced image for reference that i am interested to draw like that

[Markus]

Here is the skeleton algorithm for outputting a chessboard:

<?php

// Chess board is 8x8
// Every row and column the colors swap.

$array = array('b', 'w');

// Rows
for ($y = 0; $y < 8; $y++) {
	// Columns
	for	($x = 0; $x < 8; $x++) {
		// print the first index of array
		print $array[0];
		// and then switch the array values.
		$array = array_reverse($array);
	}
	print "\n";
	$array = array_reverse($array);
}

[neovantage]

Yeh thx but how can i integrate this with my script.
I mean say i want to create an image of chess like pattern

<?
header("Content-type: image/jpeg");
$t_im = imagecreatetruecolor("50","50");
$blue = imagecolorallocate($t_im,149,0,0);
imagefilledrectangle($t_im,0,0,$t_wt,$t_ht,$blue);
?>

How can i apply your given algorithm in this code

[Markus]

Hi, Neo.

Please have a look at the following code - do your best to understand it and ask questions if you don't.

Mark.

<?php

// Create image of set size - must be divisible by 8 
// (8 columns / rows in a chess board)
$img = imagecreatetruecolor(160, 160);

// define the colors
// these are in an array so we can conveniently and 
// efficiently reverse them.
$colors = array(
	imagecolorallocate($img, 255, 0, 0), // Red
	imagecolorallocate($img, 0, 0, 255)	 // Blue
);

// 8 rows
for ($y = 0; $y < 8; $y++) {
	// 8 columns
	for ($x = 0; $x < 8; $x++) {
		// Fill in a rectangle on our main image
		imagefilledrectangle(
			// the image resource (line 5)
			$img,
			// The starting x co-ordinate
			// If we are on loop 2 of the outter loop, $y would be 1.
			// The following line would evaluate to (1 * 20) 20. Ergo, the 
			// coord would be plotted at that position (from the top).
			// The 20 here is our rectangle height (as is with all the following
			// 20s)
			($y * 20),
			// The starting y co-ordinate.
			($x * 20),
			// This time we add 20 to our starting x coord to find our
			// ending x coord.
			($y * 20) + 20,
			// Etc.
			($x * 20) + 20,
			// Pick the first color index.
			$colors[0]
		);
		// Switch the colors to achieve alternating colors.
		$colors = array_reverse($colors);
	}
	// Again switch the colors.
	// Take this out to see why we do this.
	$colors = array_reverse($colors);
}

header("content-type: image/png");

imagepng($img);
imagedestroy($img);

[neovantage]

Thanks it works but i did a lit alteration in this code.

$t_im = imagecreatetruecolor($t_wt,$t_ht);
	    $t2_im = imagecreatetruecolor($t2_wt,$t2_ht);
	    
		$fekete = imagecolorallocate($t_im,255,115,114);
		$feher = imagecolorallocate($t_im,226,227,228);
		
		imagefill($t_im,0,0,$feher);
		$max_x = ceil($t_wt / 10);
		$max_y = ceil($t_ht / 10);
		$x = 0;
		$y = 0;
		for($i = 1; $i <= $max_y; $i++){
			if(($i%2) == 0){
				$x = 0;
			}else{
				$x = 10;
			}
			for($j = 1; $j <= $max_x; $j++){
				imagefilledrectangle($t_im,$x,$y,($x+10),($y+10),$fekete);
				$x = $x + 20;
			}
			$y+=10;
		}

Once again thanks a lot for this sir