imagecolortransparent

(PHP 4, PHP 5)

imagecolortransparent — Define a color as transparent

설명

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

Sets the transparent color in the given image .

인수

image: imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.
color: A color identifier created with imagecolorallocate().

반환값

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

예제

Example #1 imagecolortransparent() example


<?php
// Create a 55x30 image
$im = imagecreatetruecolor(55, 30);
$red = imagecolorallocate($im, 255, 0, 0);
$black = imagecolorallocate($im, 0, 0, 0);

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

// Draw a red rectangle
imagefilledrectangle($im, 4, 4, 50, 25, $red);

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

위 예제의 출력 예시:

주의

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

Note: 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.