Page 276 - Open Soource Technologies 304.indd

Web Technologies-I

Notes Load the template image, find the correct position to properly center your text, add the text to
the canvas, and send the image to the browser:
// Configuration settings
$image = ImageCreateFromPNG(‘button.png’);
$text = $_GET[‘text’];

$font = ImagePSLoadFont(‘Times’);
$size = 24;
$color = ImageColorAllocate($image, 0, 0, 0); // black

$bg_color = ImageColorAllocate($image, 255, 255, 255);// white
// Print centered text
list($x, $y) = pc_ImagePSCenter($image, $text, $font, $size);

ImagePSText($image, $text, $font, $size, $color, $bg_color, $x, $y);
// Send image header(‘Content-type: image/png’);
ImagePNG($image); // Clean up Image

PSFreeFont($font);
ImageDestroy($image);
Building dynamic images with GD is easy; all you need to do is to combine a few recipes together.
At the top of the code in the Solution, we load in an image from a stock template button; it acts
as the background on which we overlay the text. We define the text to come directly from the
query string. Alternatively, we can pull the string from a database (in the case of access counters)
or a remote server (stock quotes or weather report icons).
After that, we continue with the other settings: loading a font and specifying its size, colour,
and background colour. Before printing the text, however, we need to compute its position;
pc_ImagePSCenter( ). Last, we serve the image, and deallocate the font and image from memory.
For example, the following code generates a page of HTML and image tags using dynamic
buttons, as shown in Figure 11.10:

<?php
if (isset($_GET[‘button’]))
{

// Configuration settings
$image = ImageCreateFromPNG(‘button.png’);
$text = $_GET[‘button’];
// dynamically generated text
$font = ImagePSLoadFont(‘Times’); $size = 24; $color = ImageColorAllocate($image, 0, 0, 0);
// black
$bg_color = ImageColorAllocate($image, 255, 255, 255); // white
// Print centered text

270 LOVELY PROFESSIONAL UNIVERSITY