I want to create a small function in PHP which takes in arguments like color, shape, transparency etc. and outputs a PNG image. I heard about PHP GD library but I want to know how can one create something as creative as soon.media.mit.edu
This is a good example, you can do virtually everything using these functions. While possible, creating an image like the one you described would be pretty hard by I have done some weird stuff with gradients, loops and colors though.
If you wanted to make an image like that dynamically based on some parameters you can always create the images beforehand in photoshop and then overlay them based on what a user selects.
There is a lot of fun you can have.
Edit: Oh by the way, if your interested giving an invalid parameter shows some of the python code that is responsible for creating the image and causing the error. It would be a good place to get some idea of the code.
2nd Edit: This is just something I have done with this sort of technology. Bear in mind it was quite a while ago. It accepts a name based on the query string and basically does a few loops with a lot of random numbers.
Here is the source code, I apologize for any stupid code/quotes. This was written quite a while ago, when I was about 14 I believe (probably many flaws).
<?php
header("Content-type:image/jpeg");
$array=array("I am a monument to all your sins", "Currently making pizza","Best before 12/7/09", "Farming Onions");
function imagettftext_cr(&$im, $size, $angle, $x, $y, $color, $fontfile, $text)
{
// retrieve boundingbox
$bbox = imagettfbbox($size, $angle, $fontfile, $text);
// calculate deviation
$dx = ($bbox[2]-$bbox[0])/2.0 - ($bbox[2]-$bbox[4])/2.0; // deviation left-right
$dy = ($bbox[3]-$bbox[1])/2.0 + ($bbox[7]-$bbox[1])/2.0; // deviation top-bottom
// new pivotpoint
It's not completely what you're looking for, but I put together a script to insert dynamic color layers into transparent images. You set it up with one-color images "layers" and to run it, feed it a hex color code. The script re-colors your layers and merges them into one image to present. Here's the code; hopefully you can get some use out of it.
function hexLighter($hex, $factor = 30) {
$new_hex = '';
$base['R'] = hexdec($hex{0}.$hex{1});
$base['G'] = hexdec($hex{2}.$hex{3});
$base['B'] = hexdec($hex{4}.$hex{5});
foreach ($base as $k => $v) {
$amount = 255 - $v;
$amount = $amount / 100;
$amount = round($amount * $factor);
$new_decimal = $v + $amount;
$new_hex_component = dechex($new_decimal);
$new_hex .= sprintf('%02.2s', $new_hex_component);
}
return $new_hex;
}
// Sanitize/Validate provided color variable
if (!isset($_GET['color']) || strlen($_GET['color']) != 6) {
header($_SERVER['SERVER_PROTOCOL'] . ' 400 Bad Request', true, 400);
exit(0);
}
if (file_exists( "cache/{$_GET['color']}.png" )) {
header( 'Content-Type: image/png' );
readfile( "cache/{$_GET['color']}.png" );
exit(0);
}
// Desired final size of image
$n_width = 50;
$n_height = 50;
// Actual size of source images
$width = 125;
$height = 125;
$image = imagecreatetruecolor($width, $height);
imagesavealpha($image, true);
imagealphablending($image, false);
$n_image = imagecreatetruecolor($n_width, $n_height);
imagesavealpha($n_image, true);
imagealphablending($n_image, false);
$black = imagecolorallocate($image, 0, 0, 0);
$transparent = imagecolorallocatealpha($image, 255, 255, 255, 127);
imagefilledrectangle($image, 0, 0, $width, $height, $transparent);
$layers = array();
$layers_processed = array();
$layers[] = array( 'src' => 'layer01.gif', 'level' => 0 ); // Border
$layers[] = array( 'src' => 'layer02.gif',