Component-Builder/admin/compiler/joomla_3/wideimage/Operation/GetMask.php

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2016-01-30 20:28:43 +00:00
<?php
/**
* @author Gasper Kozak
* @copyright 2007-2011
This file is part of WideImage.
WideImage is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
WideImage is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with WideImage; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
* @package Internal/Operations
**/
/**
* GetMask operation class
*
* @package Internal/Operations
*/
class WideImage_Operation_GetMask
{
/**
* Returns a mask
*
* @param WideImage_Image $image
* @return WideImage_Image
*/
function execute($image)
{
$width = $image->getWidth();
$height = $image->getHeight();
$mask = WideImage_TrueColorImage::create($width, $height);
$mask->setTransparentColor(-1);
$mask->alphaBlending(false);
$mask->saveAlpha(false);
for ($i = 0; $i <= 255; $i++)
$greyscale[$i] = ImageColorAllocate($mask->getHandle(), $i, $i, $i);
imagefilledrectangle($mask->getHandle(), 0, 0, $width, $height, $greyscale[255]);
$transparentColor = $image->getTransparentColor();
$alphaToGreyRatio = 255 / 127;
for ($x = 0; $x < $width; $x++)
for ($y = 0; $y < $height; $y++)
{
$color = $image->getColorAt($x, $y);
if ($color == $transparentColor)
$rgba['alpha'] = 127;
else
$rgba = $image->getColorRGB($color);
imagesetpixel($mask->getHandle(), $x, $y, $greyscale[255 - round($rgba['alpha'] * $alphaToGreyRatio)]);
}
return $mask;
}
}