imagettfbbox

(PHP 4, PHP 5)

imagettfbbox — Give the bounding box of a text using TrueType fonts

Description

array imagettfbbox ( float $size , float $angle , string $fontfile , string $text )

This function calculates and returns the bounding box in pixels for a TrueType text.

Parameters

size

The font size.

Note: In GD 1, this is measured in pixels. In GD 2, this is measured in points.

angle

Angle in degrees in which text will be measured.

fontfile

The name of the TrueType font file (can be a URL). Depending on which version of the GD library that PHP is using, it may attempt to search for files that do not begin with a leading '/' by appending '.ttf' to the filename and searching along a library-defined font path.

text

The string to be measured.

Return Values

imagettfbbox() returns an array with 8 elements representing four points making the bounding box of the text on success and FALSE on error.

key contents
0 lower left corner, X position
1 lower left corner, Y position
2 lower right corner, X position
3 lower right corner, Y position
4 upper right corner, X position
5 upper right corner, Y position
6 upper left corner, X position
7 upper left corner, Y position

The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner seeing the text horizontally.

Examples

Example #1 imagettfbbox() example

<?php
// Create a 300x150 image
$im = imagecreatetruecolor(300, 150);
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);

// Set the background to be white
imagefilledrectangle($im, 0, 0, 299, 299, $white);

// Path to our font file
$font = './arial.ttf';

// First we create our bounding box for the first text
$bbox = imagettfbbox(10, 45, $font, 'Powered by PHP ' . phpversion());

// This is our cordinates for X and Y
$x = $bbox[0] + (imagesx($im) / 2) - ($bbox[4] / 2) - 25;
$y = $bbox[1] + (imagesy($im) / 2) - ($bbox[5] / 2) - 5;

// Write it
imagettftext($im, 10, 45, $x, $y, $black, $font, 'Powered by PHP ' . phpversion());

// Create the next bounding box for the second text
$bbox = imagettfbbox(10, 45, $font, 'and Zend Engine ' . zend_version());

// Set the cordinates so its next to the first text
$x = $bbox[0] + (imagesx($im) / 2) - ($bbox[4] / 2) + 10;
$y = $bbox[1] + (imagesy($im) / 2) - ($bbox[5] / 2) - 5;

// Write it
imagettftext($im, 10, 45, $x, $y, $black, $font, 'and Zend Engine ' . zend_version());

// Output to browser
header('Content-Type: image/png');

imagepng($im);
imagedestroy($im);
?>

Notes

Note:

This function requires both the GD library and the » FreeType library.

See Also