http://skypher.com/index.php/2008/05/26/mandelbrot-in-php/ The blog for absolutely nothing! Fri, 25 Jun 2010 07:02:27 +0000 hourly 1 http://wordpress.org/?v=3.0 http://skypher.com/index.php/2008/05/26/mandelbrot-in-php/comment-page-1/#comment-663 Cipher Thu, 28 Jan 2010 20:05:59 +0000 http://skypher.com/?p=12#comment-663 Terribly sorry about this. Here is the code. provide ?w=500&h=500 for width and height, there are no default values. <code> <?php /* Timing */ set_time_limit(0); function microtime_float() { list($usec, $sec) = explode(' ', microtime()); return ((float)$usec + (float)$sec); } $time_start = microtime_float(); /* Lil Mandlebrot Set Fractal Generator */ define ('IMAGE_WIDTH', intval($_GET['w'])); define ('IMAGE_HEIGHT', intval($_GET['h'])); define ('X_MIN', -1.8); define ('X_MAX', 0.5); define ('Y_MIN', -1); define ('Y_MAX', 1); define ('MAX_ITERATIONS', 100); // if you change this to a number bigger than 200, make sure you create a new palette.png $image = imagecreate(IMAGE_WIDTH, IMAGE_HEIGHT); // Load the palette to find colours $colours = array(); $palette = imagecreatefrompng('palette.png'); $i_width = imagesx($palette); for ($i=0; $i<$i_width; ++$i) { $rgb = imagecolorat($palette, $i, 0); $colours[$i] = imagecolorallocate($image, ($rgb >> 16) & 0xFF, ($rgb >> 8) & 0xFF, $rgb & 0xFF); } $colours[MAX_ITERATIONS+1] = imagecolorallocate($image, 0, 0, 0); $value_Y = (Y_MAX - Y_MIN) / (IMAGE_HEIGHT-1); $value_X = (X_MAX - X_MIN) / (IMAGE_WIDTH-1); for ($i=0; $i<IMAGE_WIDTH; ++$i) { for ($j=0; $j<IMAGE_HEIGHT; ++$j) { // What values of x and y does this pixel represent? $x = X_MIN+$i*$value_X; $y = Y_MIN+$j*$value_Y; // C=x+yi $iteration = 0; $z0 = 0; // The initial value of z is 0+0i $z1 = 0; // The initial value of z is 0+0i //$magnitude = 0; // Optimization: Store x^2 and y^2 so we don't have to keep calculating it $x2 = 0; $y2 = 0; // If the |z| > 2 ever, then the sequence will tend to infinity so we can exit the loop while ($iteration <= MAX_ITERATIONS && $x2+$y2 <= 4) { // In order to get the next term in the sequence // we need to square the previous number and then add // the original complex number $k0 = $z0; $k1 = $z1; // z is a complex number. When we square a complex number in the form x+yi: // New real component: x^2-y^2 // New imaginary component: 2*real*imaginary $z0 = $x2 - $y2+ $x; $z1 = 2 * $k0 * $k1 + $y; $x2 = $z0 * $z0; $y2 = $z1 * $z1; ++$iteration; } imagesetpixel($image, $i, $j, $colours[$iteration]); } } $time_end = microtime_float(); $black = imagecolorallocate($image, 255, 255, 255); $font = 'E:\Documents\Websites\arial.ttf'; imagettftext($image, 12, 0, 12, 12, $black, $font, ($time_end - $time_start)); header('Content-type: image/png'); imagepng($image); ?> </code> Terribly sorry about this. Here is the code. provide ?w=500&h=500 for width and height, there are no default values.

< ?php
/* Timing */
set_time_limit(0);
function microtime_float() {
list($usec, $sec) = explode(' ', microtime());
return ((float)$usec + (float)$sec);
}
$time_start = microtime_float();
/* Lil Mandlebrot Set Fractal Generator */
define ('IMAGE_WIDTH', intval($_GET['w']));
define ('IMAGE_HEIGHT', intval($_GET['h']));
define ('X_MIN', -1.8);
define ('X_MAX', 0.5);
define ('Y_MIN', -1);
define ('Y_MAX', 1);
define ('MAX_ITERATIONS', 100); // if you change this to a number bigger than 200, make sure you create a new palette.png
$image = imagecreate(IMAGE_WIDTH, IMAGE_HEIGHT);
// Load the palette to find colours
$colours = array();
$palette = imagecreatefrompng('palette.png');
$i_width = imagesx($palette);
for ($i=0; $i<$i_width; ++$i) {
$rgb = imagecolorat($palette, $i, 0);
$colours[$i] = imagecolorallocate($image, ($rgb >> 16) & 0xFF, ($rgb >> & 0xFF, $rgb & 0xFF);
}
$colours[MAX_ITERATIONS+1] = imagecolorallocate($image, 0, 0, 0);
$value_Y = (Y_MAX - Y_MIN) / (IMAGE_HEIGHT-1);
$value_X = (X_MAX - X_MIN) / (IMAGE_WIDTH-1);
for ($i=0; $i for ($j=0; $j // What values of x and y does this pixel represent?
$x = X_MIN+$i*$value_X;
$y = Y_MIN+$j*$value_Y;
// C=x+yi
$iteration = 0;
$z0 = 0; // The initial value of z is 0+0i
$z1 = 0; // The initial value of z is 0+0i
//$magnitude = 0;
// Optimization: Store x^2 and y^2 so we don't have to keep calculating it
$x2 = 0;
$y2 = 0;
// If the |z| > 2 ever, then the sequence will tend to infinity so we can exit the loop
while ($iteration < = MAX_ITERATIONS && $x2+$y2 <= 4) {
// In order to get the next term in the sequence
// we need to square the previous number and then add
// the original complex number
$k0 = $z0;
$k1 = $z1;
// z is a complex number. When we square a complex number in the form x+yi:
// New real component: x^2-y^2
// New imaginary component: 2*real*imaginary
$z0 = $x2 - $y2+ $x;
$z1 = 2 * $k0 * $k1 + $y;
$x2 = $z0 * $z0;
$y2 = $z1 * $z1;
++$iteration;
}
imagesetpixel($image, $i, $j, $colours[$iteration]);
}
}
$time_end = microtime_float();
$black = imagecolorallocate($image, 255, 255, 255);
$font = 'E:\Documents\Websites\arial.ttf';
imagettftext($image, 12, 0, 12, 12, $black, $font, ($time_end - $time_start));
header('Content-type: image/png');
imagepng($image);
?>


]]> http://skypher.com/index.php/2008/05/26/mandelbrot-in-php/comment-page-1/#comment-662 George Thu, 28 Jan 2010 00:54:38 +0000 http://skypher.com/?p=12#comment-662 are you going to post the code anytime soon? are you going to post the code anytime soon?

]]> http://skypher.com/index.php/2008/05/26/mandelbrot-in-php/comment-page-1/#comment-14 zylox Fri, 27 Jun 2008 14:22:33 +0000 http://skypher.com/?p=12#comment-14 hi! have you got any news on this? i would be interested, also in the sourcecode! hi! have you got any news on this? i would be interested, also in the sourcecode!

]]> http://skypher.com/index.php/2008/05/26/mandelbrot-in-php/comment-page-1/#comment-3 Eric Tue, 27 May 2008 10:39:58 +0000 http://skypher.com/?p=12#comment-3 Nice example, curious for the results. Lets use the DH server for real-time fractal rendering ;) Nice example, curious for the results.
Lets use the DH server for real-time fractal rendering

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