Php/docs/function.imagelayereffect
imagelayereffect
(PHP 4 >= 4.3.0, PHP 5, PHP 7)
imagelayereffect — 设定 alpha 混色标志以使用绑定的 libgd 分层效果
说明
imagelayereffect
( resource $image
, int $effect
) : bool
设定 alpha 混色标志以使用绑定的 libgd 分层效果。
参数
image- 由图象创建函数(例如imagecreatetruecolor())返回的图象资源。
effect- One of the following constants:
IMG_EFFECT_REPLACE- Use pixel replacement (equivalent of passing
trueto imagealphablending()) IMG_EFFECT_ALPHABLEND- Use normal pixel blending (equivalent of passing
falseto imagealphablending()) IMG_EFFECT_NORMAL- Same as
IMG_EFFECT_ALPHABLEND. IMG_EFFECT_OVERLAY- Overlay has the effect that black background pixels will remain black, white background pixels will remain white, but grey background pixels will take the colour of the foreground pixel.
返回值
成功时返回 true， 或者在失败时返回 false。
范例
Example #1 imagelayereffect() example
<?php// Setup an image$im = imagecreatetruecolor(100, 100);// Set a backgroundimagefilledrectangle($im, 0, 0, 100, 100, imagecolorallocate($im, 220, 220, 220));// Apply the overlay alpha blending flagimagelayereffect($im, IMG_EFFECT_OVERLAY);// Draw two grey ellipsesimagefilledellipse($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($im, 255, 100, 100));// Outputheader('Content-type: image/png');imagepng($im);imagedestroy($im);?>
以上例程的输出类似于：
