Category: Source

<?php

/**
 * unique_image
 *
 * Generate a pseudo-unique "hash" image based on a string.
 *
 * @version 0.3
 * @author Contributors at eXorithm
 * @link /algorithm/view/unique_image Listing at eXorithm
 * @link /algorithm/history/unique_image History at eXorithm
 * @license /home/show/license
 *
 * @param mixed $string 
 * @return resource GD image
 */
function unique_image($string='whatever')
{
	$size=200;
	$steps=5;
	$step=$size/$steps;
	
	$image = image_create_alpha($size, $size);
	
	$n = 0;
	$prev = 0;
	$len = strlen($string);
	$sum = 0;
	for ($i=0;$i<$len;$i++) $sum += ord($string[$i]);
	
	for ($i=0;$i<$steps;$i++) {
		for ($j=0;$j<$steps;$j++) {
			$letter = $string[$n++ % $len];
			
			$u = ($n % (ord($letter)+$sum)) + ($prev % (ord($letter)+$len)) + (($sum-1) % ord($letter));
			$color = imagecolorallocate($image, pow($u*$prev+$u+$prev+5,2)%256, pow($u*$prev+$u+$prev+3,2)%256, pow($u*$prev+$u+$prev+1,2)%256);
			if (($u%2)==0)
				imagefilledpolygon($image, array($i*$step, $j*$step, $i*$step+$step, $j*$step, $i*$step, $j*$step+$step), 3, $color);
			$prev = $u;
			
			$u = ($n % (ord($letter)+$len)) + ($prev % (ord($letter)+$sum)) + (($sum-1) % ord($letter));
			if (($u%2)==0)
				imagefilledpolygon($image, array($i*$step, $j*$step+$step, $i*$step+$step, $j*$step+$step, $i*$step+$step, $j*$step), 3, $color);
			$prev = $u;
		
		}
	}
	
	return $image;
}

/**
 * image_create_alpha
 *
 * Helper function to create a new blank image with transparency.
 *
 * @version 0.1
 * @author Contributors at eXorithm
 * @link /algorithm/view/image_create_alpha Listing at eXorithm
 * @link /algorithm/history/image_create_alpha History at eXorithm
 * @license /home/show/license
 *
 * @param mixed $width 
 * @param mixed $height 
 * @return resource GD image
 */
function image_create_alpha($width='',$height='')
{
	// Create a normal image and apply required settings
	$img = imagecreatetruecolor($width, $height);
	imagealphablending($img, false);
	imagesavealpha($img, true);
	
	// Apply the transparent background
	$trans = imagecolorallocatealpha($img, 0, 0, 0, 127);
	for ($x = 0; $x < $width; $x++)
	{
		for ($y = 0; $y < $height; $y++)
		{
			imagesetpixel($img, $x, $y, $trans);
		}
	}
	
	return $img;
}

?>

<?php

/**
 * simple_sort
 *
 * Sort an array and display it.
 *
 * @version 0.1
 * @author Contributors at eXorithm
 * @link /algorithm/view/simple_sort Listing at eXorithm
 * @link /algorithm/history/simple_sort History at eXorithm
 * @license /home/show/license
 *
 * @param array $array 
 * @return array
 */
function simple_sort($array=array(0=>'1',1=>'11',2=>'22',3=>'3',4=>'4'))
{
	sort($array);
	return $array;
}

?>

<?php

/**
 * magic8ball
 *
 * Ask the magic 8 ball your question.
 *
 * @version 0.2
 * @author Contributors at eXorithm
 * @link /algorithm/view/magic8ball Listing at eXorithm
 * @link /algorithm/history/magic8ball History at eXorithm
 * @license /home/show/license
 *
 * @return mixed
 */
function magic8ball()
{
	$answers =array('It is certain', 'It is decidedly so', 'Without a doubt',
				'Yes – definitely', 'You may rely on it', 'As I see it, yes',
				'Most likely', 'Outlook good', 'Signs point to yes', 'Yes',
				'Reply hazy, try again', 'Ask again later',
				'Better not tell you now', 'Cannot predict now',
				'Concentrate and ask again', 'Don\'t bet on it',
				'My reply is no', 'My sources say no', 'Outlook not so good',
				'Very doubtful' );
	
	$index = rand(0, count($answers));
	return ($answers[$index]);
}

?>

<?php

/**
 * stock_ticker
 *
 * Generate an HTML stock ticker with current quotes.
 *
 * @version 3.2
 * @author Contributors at eXorithm
 * @link /algorithm/view/stock_ticker Listing at eXorithm
 * @link /algorithm/history/stock_ticker History at eXorithm
 * @license /home/show/license
 *
 * @param array $symbols stocks to go in the ticker
 * @param string $background_color (hex color code) color of the ticker background
 * @param string $stock_color (hex color code) color of the stock symbols
 * @param string $price_color (hex color code) color of the prices
 * @param string $up_color (hex color code) color of gains
 * @param string $down_color (hex color code) color of loses
 * @param number $speed speed of scrolling 
 * @return string HTML
 */
function stock_ticker($symbols=array(0=>'AAPL',1=>'GOOG',2=>'DOW',3=>'GCG13.CMX',4=>'P'),$background_color='dddddd',$stock_color='000000',$price_color='0000bb',$up_color='008000',$down_color='ff0000',$speed=6)
{
	sort($symbols);
	
	if ($background_color==$stock_color) {
		// something's wrong, colors weren't specified
		$background_color = invert_color($background_color);
	}
	
	$return = '<div align="center">
	<marquee bgcolor="#'.$background_color.'" loop="20" scrollamount="'.$speed.'">';
	
	foreach ($symbols as $symbol) {
		$data = file_get_contents("http://quote.yahoo.com/d/quotes.csv?s=$symbol&f=sl1d1t1c1ohgv&e=.csv");
		
		$values = explode(",", $data);
		$lasttrade = $values[1];
		$change = $values[4];
		
		$return .= "<span style=\"color:#$stock_color\">$symbol</span> &nbsp;";
		$return .= "<span style=\"color:#$price_color\">$lasttrade</span> &nbsp;";
		if ($change<0)
			$return .= "<span style=\"color:#$down_color\">$change</span> &nbsp;";
		else
			$return .= "<span style=\"color:#$up_color\">$change</span> &nbsp;";
		$return .= "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;";
	}
	
	$return .= '</marque>
	</div>';
	
	return $return;
}

/**
 * invert_color
 *
 * Invert a color.
 *
 * @version 0.1
 * @author Contributors at eXorithm
 * @link /algorithm/view/invert_color Listing at eXorithm
 * @link /algorithm/history/invert_color History at eXorithm
 * @license /home/show/license
 *
 * @param string $color (hex color code) 
 * @return string hex color code
 */
function invert_color($color='008080')
{
	$new = '';
	for ($i=0;$i<3;$i++){
		$c = 255 - hexdec(substr($color,(2*$i),2));
		$c = dechex($c);
		$new .= (strlen($c) < 2) ? '0'.$c : $c;
	}
	return $new;
}

?>

<?php

/**
 * draw_cube
 *
 * Draw a 3d cube.
 *
 * @version 0.8
 * @author Contributors at eXorithm
 * @link /algorithm/view/draw_cube Listing at eXorithm
 * @link /algorithm/history/draw_cube History at eXorithm
 * @license /home/show/license
 *
 * @param number $image_size Size of the resulting image.
 * @param number $degree_x Degrees to rotate around the x axis.
 * @param number $degree_y Degrees to rotate around the y axis.
 * @param number $degree_z Degrees to rotate around the z axis.
 * @param number $vdist Distance to vanishing point.
 * @param number $dist Distance from origin. This number should not be less than 0 (or else you will be inside the cube!)
 * @param string $vertex_color (hex color code) Color of the vertices of the cube.
 * @param string $face_color (hex color code) Color of the face of the cube.
 * @param bool $wireframe Display as a wireframe (face color will be ignored).
 * @param bool $dashes Display "hidden" lines as dashes (only if wireframe is not selected).
 * @param bool $rainbow Instead of using the face color, draw each side a different color.
 * @return resource GD image
 */
function draw_cube($image_size=400,$degree_x=35,$degree_y=35,$degree_z=0,$vdist=800,$dist=100,$vertex_color='0000ff',$face_color='ff0000',$wireframe=false,$dashes=false,$rainbow=false)
{
	$degree_x = $degree_x % 360;
	$degree_y = $degree_y % 360;
	$degree_z = $degree_z % 360;
	
	// construct the cube polygons
	$size = 400; // the size is arbitrary
	
	$x1=$size/2;
	$x0=-($size/2);
	$y1=$size/2;
	$y0=-($size/2);
	$z1=$size/2;
	$z0=-($size/2);
	
	$sides = array();
	
	$sides[] = array($x0,$y0,$z0, $x0,$y0,$z1, $x0,$y1,$z1, $x0,$y1,$z0);
	$sides[] = array($x1,$y0,$z0, $x1,$y0,$z1, $x1,$y1,$z1, $x1,$y1,$z0);
	
	$sides[] = array($x0,$y0,$z0, $x0,$y0,$z1, $x1,$y0,$z1, $x1,$y0,$z0);
	$sides[] = array($x0,$y1,$z0, $x0,$y1,$z1, $x1,$y1,$z1, $x1,$y1,$z0);
	
	$sides[] = array($x0,$y0,$z0, $x0,$y1,$z0, $x1,$y1,$z0, $x1,$y0,$z0);
	$sides[] = array($x0,$y0,$z1, $x0,$y1,$z1, $x1,$y1,$z1, $x1,$y0,$z1);
	
	// project each of the 6 polygons that makes up the cube
	for ($i=0; $i<count($sides); $i++) {
		$points[] = project_polygon($sides[$i], $degree_x, $degree_y, $degree_z, 0, 0, 0, $vdist+($size/2), $dist+($size/2), true);
	}
	
	// scale the image somewhat
	$scale = $image_size/($size*1.8);
	
	if ($rainbow) {
		$face_color = array('ff0000', '00d000', 'ffff00', 'a000a0', '0000ff', 'FF8040');
	}
	
	return render_polygons($points, $vertex_color, $face_color, $wireframe, $dashes, $image_size, $scale);
}

/**
 * project_polygon
 *
 * Project a the points of a 3d polygon onto a flat 2d surface (the screen).
 *
 * @version 0.5
 * @author Contributors at eXorithm
 * @link /algorithm/view/project_polygon Listing at eXorithm
 * @link /algorithm/history/project_polygon History at eXorithm
 * @license /home/show/license
 *
 * @param array $points Points of the polygon, in the form x1, y1, z1, x2, y2, z2, etc.
 * @param number $degree_x Degrees to rotate around the x axis.
 * @param number $degree_y Degrees to rotate around the y axis.
 * @param number $degree_z Degrees to rotate around the z axis.
 * @param number $center_x Location to center the view on.
 * @param number $center_y Location to center the view on.
 * @param number $center_z Location to center the view on.
 * @param number $dist1 Distance from viewer to screen (distance to vanishing point).
 * @param number $dist2 Distance from screen to object.
 * @param bool $include_z Return the z (distance) parameter for each point as well.
 * @return mixed
 */
function project_polygon($points=array(0=>'-1',1=>'-1',2=>'0',3=>'-1',4=>'1',5=>'0',6=>'1',7=>'1',8=>'0',9=>'1',10=>'-1',11=>'0'),$degree_x=45,$degree_y=45,$degree_z=45,$center_x=0,$center_y=0,$center_z=0,$dist1=5,$dist2=2,$include_z=false)
{
	// check points
	if ((count($points)%3)!=0) {
		throw new Exception('The points must be a list like x1, y1, z1, x2, y2, z2, etc. The number of points therefore must be divisible by three.');
	}
	
	$degree_x = deg2rad($degree_x);
	$degree_y = deg2rad($degree_y);
	$degree_z = deg2rad($degree_z);
	
	$cosx = cos($degree_x);
	$sinx = sin($degree_x);
	$cosy = cos($degree_y);
	$siny = sin($degree_y);
	$cosz = cos($degree_z);
	$sinz = sin($degree_z);
	
	$array = array();
	
	for ($i=0;$i<count($points);$i=$i+3) {
		$x0 = $points[$i]-$center_x;
		$y0 = $points[$i+1]-$center_y;
		$z0 = $points[$i+2]-$center_z;
		
		$x1 = $cosy*($sinz*$y0 + $cosz*$x0) - $siny*$z0;
		$y1 = $sinx*($cosy*$z0 + $siny*($sinz*$y0 + $cosz*$x0)) + $cosx*($cosz*$y0 - $sinz*$x0);
		$z1 = $cosx*($cosy*$z0 + $siny*($sinz*$y0 + $cosz*$x0)) - $sinx*($cosz*$y0 - $sinz*$x0);
	
		$x2 = $x1*$dist1/($z1+$dist1+$dist2);
		$y2 = $y1*$dist1/($z1+$dist1+$dist2);
		$z2 = $z1*$dist1/($z1+$dist1+$dist2);
	
		$array[] = $x2;
		$array[] = $y2;
		if ($include_z) $array[] = $z2;
	}
	
	return $array;
}

/**
 * render_polygons
 *
 * Helper function to render polygons to the screen with a number of options.
 *
 * @version 0.5
 * @author Contributors at eXorithm
 * @link /algorithm/view/render_polygons Listing at eXorithm
 * @link /algorithm/history/render_polygons History at eXorithm
 * @license /home/show/license
 *
 * @param array $polygons Multi-dimensional array. Each element will be an array of points (x1, y1, z1, x2, y2, z2, etc).
 * @param string $vertex_color (hex color code) Color of the vertices of the polygons.
 * @param string $face_color (hex color code) Color of the faces of the polygons.
 * @param bool $wireframe Display as a wireframe (face color will be ignored).
 * @param bool $dashes Display "hidden" vertices as dashes (only if wireframe is not selected).
 * @param number $image_size Size of the resulting image.
 * @param number $scale Scale factor. Set to 0 to auto-scale (fill the image).
 * @return resource GD image
 */
function render_polygons($polygons=array(0=>array(0=>-100,1=>-100,2=>1,3=>0,4=>100,5=>1,6=>100,7=>-100,8=>1)),$vertex_color='000000',$face_color='ffd700',$wireframe=false,$dashes=false,$image_size=300,$scale=1)
{
	foreach ($polygons as $polygon) {
		if (!is_array($polygon)) {
			throw new Exception('Each polygon must be a list.');
		} else if ((count($polygon)%3)!=0) {
			throw new Exception('Each polygon must be a list like x1, y1, z1, x2, y2, z2, etc. The number of points therefore must be divisible by three.');
		}
	}
	
	if (is_array($vertex_color)) {
		if (count($vertex_color) != count($polygons)) {
			throw new Exception('If vertex colors is an array, it must contain the same number of colors as the number of polygons.');
		}
	}
	
	if (is_array($face_color)) {
		if (count($face_color) != count($polygons)) {
			throw new Exception('If face colors is an array, it must contain the same number of colors as the number of polygons.');
		}
	}
	
	// if scale=0 then we auto-scale
	if ($scale==0) {
		$max = 0;
		for ($i=0; $i<count($polygons); $i++) {
			for ($j=0; $j<count($polygons[$i]); $j=$j+3) {  
				if (abs($polygons[$i][$j])>$max)
					$max = abs($polygons[$i][$j]);
				if (abs($polygons[$i][$j+1])>$max)
					$max = abs($polygons[$i][$j+1]);
			}
		}
		if ($max>0)
			$scale = ($image_size-2)/($max*2);
	}
	
	// the polygon arrays (x,y,z) must be converted into shapes (x,y)
	$shapes = array();
	$z_max = array();
	
	for ($i=0; $i<count($polygons); $i++) {
		$max = $polygons[$i][2];
		for ($j=0; $j<count($polygons[$i]); $j=$j+3) {  
			$x = $polygons[$i][$j];
			$y = $polygons[$i][$j+1];
			
			// map each x,y coord to a screen position
			$x = round($image_size/2 + $x*$scale);
			$y = round($image_size/2 - $y*$scale);
			
			$shapes[$i][$j] = $x;
			$shapes[$i][$j+1] = $y;
			
			// keep track of the maximum z-value for each shape
			if ($polygons[$i][$j+2]>$max)
				$max = $polygons[$i][$j+2];
		}
		$shapes[$i] = array_values($shapes[$i]);
		$z_max[$i] = $max;
	}
	
	// create a blank image
	$image = image_create_alpha($image_size, $image_size);
	
	// create the colors
	if (!is_array($vertex_color))
		$vertex_color = array_fill(0, count($polygons), $vertex_color);
	if (!is_array($face_color))
		$face_color = array_fill(0, count($polygons), $face_color);
	
	// painter's algorithm - draw farther polygons first
	array_multisort($z_max, SORT_DESC, $shapes, $face_color, $vertex_color);
	
	// draw the polygons
	for ($i=0; $i<count($shapes); $i++) {
		$v_color = allocate_color($image, $vertex_color[$i]);
		$f_color = allocate_color($image, $face_color[$i]);
		if (!$wireframe) {
			imagefilledpolygon($image, $shapes[$i], count($shapes[$i])/2, $f_color);
		}
		imagepolygon($image, $shapes[$i], count($shapes[$i])/2, $v_color);
	}
	
	// draw dashes - BUGGY
	if ($dashes) {
		for ($i=0; $i<count($shapes); $i++) {
			$v_color = allocate_color($image, $vertex_color[$i]);
			$style = array($v_color, IMG_COLOR_TRANSPARENT, IMG_COLOR_TRANSPARENT, IMG_COLOR_TRANSPARENT, IMG_COLOR_TRANSPARENT);
			imagesetstyle($image, $style);
			imagepolygon($image, $shapes[$i], count($shapes[$i])/2, IMG_COLOR_STYLED);
		}
	}
	
	return $image;
}

/**
 * image_create_alpha
 *
 * Helper function to create a new blank image with transparency.
 *
 * @version 0.1
 * @author Contributors at eXorithm
 * @link /algorithm/view/image_create_alpha Listing at eXorithm
 * @link /algorithm/history/image_create_alpha History at eXorithm
 * @license /home/show/license
 *
 * @param mixed $width 
 * @param mixed $height 
 * @return resource GD image
 */
function image_create_alpha($width='',$height='')
{
	// Create a normal image and apply required settings
	$img = imagecreatetruecolor($width, $height);
	imagealphablending($img, false);
	imagesavealpha($img, true);
	
	// Apply the transparent background
	$trans = imagecolorallocatealpha($img, 0, 0, 0, 127);
	for ($x = 0; $x < $width; $x++)
	{
		for ($y = 0; $y < $height; $y++)
		{
			imagesetpixel($img, $x, $y, $trans);
		}
	}
	
	return $img;
}

/**
 * allocate_color
 *
 * Helper function to allocate a color to an image. Color should be a 6-character hex string.
 *
 * @version 0.2
 * @author Contributors at eXorithm
 * @link /algorithm/view/allocate_color Listing at eXorithm
 * @link /algorithm/history/allocate_color History at eXorithm
 * @license /home/show/license
 *
 * @param resource $image (GD image) The image that will have the color allocated to it.
 * @param string $color (hex color code) The color to allocate to the image.
 * @param mixed $transparency The level of transparency from 0 to 127.
 * @return mixed
 */
function allocate_color($image=null,$color='268597',$transparency='0')
{
	if (preg_match('/[0-9ABCDEF]{6}/i', $color)==0) {
		throw new Exception("Invalid color code.");
	}
	if ($transparency<0 || $transparency>127) {
		throw new Exception("Invalid transparency.");
	}
	
	$r  = hexdec(substr($color, 0, 2));
	$g  = hexdec(substr($color, 2, 2));
	$b  = hexdec(substr($color, 4, 2));
	if ($transparency>127) $transparency = 127;
	
	if ($transparency<=0)
		return imagecolorallocate($image, $r, $g, $b);
	else
		return imagecolorallocatealpha($image, $r, $g, $b, $transparency);
}

?>