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imageantialias

PHP function Edit on GitHub ✎

(PHP 4 >= 4.3.2, PHP 5, PHP 7, PHP 8)

Should antialias functions be used or not

Description

imageantialias(GdImage $image, bool $enable): true

Activate the fast drawing antialiased methods for lines and wired polygons. It does not support alpha components. It works using a direct blend operation. It works only with truecolor images.

Thickness and styled are not supported.

Using antialiased primitives with transparent background color can end with some unexpected results. The blend method uses the background color as any other colors. The lack of alpha component support does not allow an alpha based antialiasing method.

Parameters

enable

Whether to enable antialiasing or not.

Return Values

Always

Changelog

VersionDescription
7.2.0imageantialias() is now generally available. Formerly it was only available if PHP was compiled with the bundled version of the GD library.

Examples

A comparison of two lines, one with anti-aliasing switched on

php
<?php
// Setup an anti-aliased image and a normal image
$aa = imagecreatetruecolor(400, 100);
$normal = imagecreatetruecolor(200, 100);

// Switch antialiasing on for one image
imageantialias($aa, true);

// Allocate colors
$red = imagecolorallocate($normal, 255, 0, 0);
$red_aa = imagecolorallocate($aa, 255, 0, 0);

// Draw two lines, one with AA enabled
imageline($normal, 0, 0, 200, 100, $red);
imageline($aa, 0, 0, 200, 100, $red_aa);

// Merge the two images side by side for output (AA: left, Normal: Right)
imagecopymerge($aa, $normal, 200, 0, 0, 0, 200, 100, 100);

// Output image
header('Content-type: image/png');

imagepng($aa);
?>

The above example will output something similar to: Output of example : A comparison of two lines, one with anti-aliasing switched on

See Also

Source: reference/image/functions/imageantialias.xml · from the official PHP manual (php/doc-en)