Draws Yin-Yang in ASCII-mode

Yin-Yang.php

<?php
	
	/*
		Draws Yin-Yang in ASCII-mode
		Usage: "php yin.php <size>"
		Size must be greater then 10
		
		Author Roman Rybalchenko mail@nerevar.ru
                http://dumpz.org/84832/
		13.09.2011
	*/

	define('EMPTY_CELL', '.');
	define('BLACK_CELL', '*');
	define('WHITE_CELL', 'x');
	
	if (empty($argv[1]) || intval($argv[1]) < 11) {
		die ("\nUsage: 'php ascii.php <size>' \nSize > 10\n");
	}
	
	$size = intval($argv[1]);
	
	// generate map
	$map = array();
	for ($i=0; $i<=$size; $i++) {
		$map[$i] = array();
		for ($j=0; $j<=$size; $j++) {
			$map[$i][$j] = EMPTY_CELL;
		}
	}
	
	// radius
	$r = $size / 2;
	$r2 = $size / 4;
	$r4 = $size / 8;

	// center
	$c_x = $size / 2;
	$c_y = $size / 2;
	
	// fill left part with white cells
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size / 2; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r) {
				$map[$i][$j] = WHITE_CELL;
			}
		}
	}	
	// fill right part with black cells
	for ($i=1; $i<=$size; $i++) {
		for ($j=$size / 2 + 1; $j<=$size; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r) {
				$map[$i][$j] = BLACK_CELL;
			}
		}
	}		

	// fill small top circle with black cells
	$c_y = $size / 4;
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r2) {
				$map[$i][$j] = BLACK_CELL;
			}
		}
	}		
	
	// fill small bottom circle with white cells
	$c_y = $size / 4 * 3;
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r2) {
				$map[$i][$j] = WHITE_CELL;
			}
		}
	}		





	// fill the smallest top circle with white cells
	$c_y = $size / 4;
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r4) {
				$map[$i][$j] = WHITE_CELL;
			}
		}
	}		
	
	// fill the smallest bottom circle with black cells
	$c_y = $size / 4 * 3;
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size; $j++) {			
			if (sqrt( ($i-$c_y)*($i-$c_y) + ($j-$c_x)*($j-$c_x) ) <= $r4) {
				$map[$i][$j] = BLACK_CELL;
			}
		}
	}		
	

	
	// print map
	for ($i=1; $i<=$size; $i++) {
		for ($j=1; $j<=$size; $j++) {
			print $map[$i][$j];
		}
		print "\n";
	}