GD and Image Функции
PHP Manual

imagecolortransparent

(PHP 4, PHP 5)

imagecolortransparentDefine a color as transparent

Описание

int imagecolortransparent ( resource $image [, int $color ] )

Sets the transparent color in the given image .

Параметри

image

Ресурс на изображение, върнат от някоя от функциите за създаване на изображения като например imagecreatetruecolor().

color

A color identifier created with imagecolorallocate().

Връщани стойности

The identifier of the new (or current, if none is specified) transparent color is returned.

Примери

Example #1 imagecolortransparent() example

<?php
// Create a 55x30 image
$im imagecreatetruecolor(5530);
$red imagecolorallocate($im25500);
$black imagecolorallocate($im000);

// Make the background transparent
imagecolortransparent($im$black);

// Draw a red rectangle
imagefilledrectangle($im445025$red);

// Save the image
imagepng($im'./imagecolortransparent.png');
imagedestroy($im);
?>

Примерът по-горе ще изведе нещо подобно на:

Бележки

Забележка: Transparency is copied only with imagecopymerge() and true color images, not with imagecopy() or pallete images.

Забележка: The transparent color is a property of the image, transparency is not a property of the color. Once you have set a color to be the transparent color, any regions of the image in that color that were drawn previously will be transparent.


GD and Image Функции
PHP Manual