imagecolortransparent

imagecolortransparent

Define a color as transparent

int **imagecolortransparent** GdImage $image  $color

Gets or sets the transparent color in the given . image

colorgd.identifier.color

The identifier of the new (or current, if none is specified) transparent color is returned. If is null, and the image has no transparent color, the returned identifier will be . color``-1

Voorbeeld: 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');
?>

Opmerking: > Transparency is copied only with and true color images, not with or pallete images. imagecopymerge``imagecopy

Opmerking: > 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.