Lab5

<?php

// ----- PHP SHOULD TELL THE BROWSER IT'S GETTING A PNG IMAGE, NOT HTML AS IS THE DEFAULT

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


// ----- GET REQUEST PARAMETERS

if (isset($_REQUEST["text"])) $text = $_REQUEST["text"];
else $text = "Networks & Transactions";


// ----- CONSTANTS

$canvasWidth = 300;
$canvasHeight = 300;


// ----- CREATE A NEW CANVAS

$canvas = imagecreatetruecolor($canvasWidth, $canvasHeight);


// ----- DEFINE A FEW COLORS

$white = imagecolorallocate($canvas, 255, 255, 255);
$blue = imagecolorallocate($canvas, 0, 255, 255);
$red = imagecolorallocate($canvas, 255, 0, 0);
$gray = imagecolorallocate($canvas, 127, 127, 127);


// ----- FILL THE BACKGROUND

// Define white as a transparent color
imagecolortransparent($canvas, $white);

// Fill the background with white starting from 0, 0
imagefill($canvas, 0, 0, $white);


// ----- SPRINKLE 5000 BLUE PIXELS

// Do 5000 times...
for ($count = 1; $count <= 5000; $count++) {
       
        // Pick a random x and y coordinate
        $x = rand(0, $canvasWidth - 1);
        $y = rand(0, $canvasHeight - 1);
       
        // Draw the pixel
        imagesetpixel($canvas, $x, $y, $blue);
}


// ----- DRAW A RED CIRCLE IN THE TOP-LEFT QUARTER OF THE IMAGE

$x = rand(0, $canvasWidth / 2);
$y = rand(0, $canvasHeight / 2);
$radius = rand(0, $canvasWidth / 2);
imagefilledellipse($canvas, $x, $y, $radius, $radius, $red);


// ----- DISPLAY ANTI-ALIASED TEXT USING A TRUETYPE FONT

$x = rand(15, $canvasWidth / 2);
$y = rand(50, $canvasHeight);
imagettftext($canvas, 28, 0, $x, $y, $gray, "5d-whitney.ttf", $text);


// ----- SUPERIMPOSE ANOTHER IMAGE THAT HAS A TRANSPARENT BACKGROUND

// Load the icon
$iconCanvas = imagecreatefrompng("5c-icon.png");

// Figure out its width and height
$iconWidth = imagesx($iconCanvas);
$iconHeight = imagesy($iconCanvas);

// Decide where to put it on the main canvas
$x = rand(0, $canvasWidth - $iconWidth);
$y = rand(0, $canvasHeight - $iconHeight);

// Copy the icon onto the main canvas...
// ...with 100% opacity, but respecting the transparency of the icon
imagecopymerge($canvas, $iconCanvas, $x, $y, 0, 0, $iconWidth, $iconHeight, 100);

// Note: Unfortunately, this works best with images that have exactly one transparent
//  (knocked out) color, not varying levels of transparency or anti-aliased edges.
//  Still working on that...


// ----- OUTPUT THE IMAGE TO THE BROWSER AS A PNG

imagepng($canvas);


?>