(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)
imagelayereffect — Set the alpha blending flag to use layering effects
Set the alpha blending flag to use layering effects.
image
Una risorsa immagine, restituita da una delle funzioni di creazione immagine, come imagecreatetruecolor().
effect
One of the following constants:
IMG_EFFECT_REPLACE
true
to
imagealphablending())
IMG_EFFECT_ALPHABLEND
false
to
imagealphablending())
IMG_EFFECT_NORMAL
IMG_EFFECT_ALPHABLEND
.
IMG_EFFECT_OVERLAY
IMG_EFFECT_MULTIPLY
Versione | Descrizione |
---|---|
8.0.0 |
image expects a GdImage
instance now; previously, a valid gd resource was expected.
|
7.2.0 |
Added IMG_EFFECT_MULTIPLY (requires system libgd >=
2.1.1 or the bundled libgd).
|
Example #1 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($im);
imagedestroy($im);
?>
Il precedente esempio visualizzerà qualcosa simile a: