imagelayereffect

Description

Set the alpha blending flag to use layering effects.

Parameters

effect

One of the following constants:

IMG_EFFECT_REPLACE

Use pixel replacement (equivalent of passing true to imagealphablending())

IMG_EFFECT_ALPHABLEND

Use normal pixel blending (equivalent of passing false to imagealphablending())

IMG_EFFECT_NORMAL

Same as IMG_EFFECT_ALPHABLEND.

IMG_EFFECT_OVERLAY

Overlay has the effect that black background pixels will remain black, white background pixels will remain white, but grey background pixels will take the colour of the foreground pixel.

IMG_EFFECT_MULTIPLY

Overlays with a multiply effect.

Return Values

Always

Changelog

Examples

imagelayereffect() example

<?php
// Setup an image
$im = imagecreatetruecolor(100, 100);

// Set a background
imagefilledrectangle($im, 0, 0, 100, 100, imagecolorallocate($im, 220, 220, 220));

// Apply the overlay alpha blending flag
imagelayereffect($im, IMG_EFFECT_OVERLAY);

// Draw two grey ellipses
imagefilledellipse($im, 50, 50, 40, 40, imagecolorallocate($im, 100, 255, 100));
imagefilledellipse($im, 50, 50, 50, 80, imagecolorallocate($im, 100, 100, 255));
imagefilledellipse($im, 50, 50, 80, 50, imagecolorallocate($im, 255, 100, 100));

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

imagepng($im);
?>

The above example will output something similar to: Output of example : imagelayereffect()