<?php
/**
* Image processor using GD.
*
* @package XenForo_Image
*/
class XenForo_Image_Gd extends XenForo_Image_Abstract
{
/**
* The GD image resource.
*
* @var resource
*/
protected $_image = null;
/**
* Constructor.
*
* @param resource $image GD image resource
*/
protected function __construct($image)
{
$this->_setImage($image);
// make sure we have enough memory for a temporary copy of this image
$memoryBuffer = ($this->_width * $this->_height * 5) * 1.25;
$availableMemory = XenForo_Application::getAvailableMemory();
if ($availableMemory && $availableMemory < $memoryBuffer)
{
XenForo_Application::increaseMemoryLimit($memoryBuffer - $availableMemory);
}
}
/**
* Creates a blank image.
*
* @param integer $width
* @param integer $height
*
* @return XenForo_Image_Gd
*/
public static function createImageDirect($width, $height)
{
$class = XenForo_Application::resolveDynamicClass(__CLASS__);
return new $class(imagecreatetruecolor($width, $height));
}
/**
* Creates an image from an existing file.
*
* @param string $fileName
* @param integer $inputType IMAGETYPE_XYZ constant representing image type
*
* @return XenForo_Image_Gd|false
*/
public static function createFromFileDirect($fileName, $inputType)
{
$invalidType = false;
try
{
switch ($inputType)
{
case IMAGETYPE_GIF:
if (!function_exists('imagecreatefromgif'))
{
return false;
}
$image = imagecreatefromgif($fileName);
break;
case IMAGETYPE_JPEG:
if (!function_exists('imagecreatefromjpeg'))
{
return false;
}
$image = imagecreatefromjpeg($fileName);
break;
case IMAGETYPE_PNG:
if (!function_exists('imagecreatefrompng'))
{
return false;
}
$image = imagecreatefrompng($fileName);
break;
default:
$invalidType = true;
}
}
catch (Exception $e)
{
return false;
}
if ($invalidType)
{
throw new XenForo_Exception('Invalid image type given. Expects IMAGETYPE_XXX constant.');
}
$class = XenForo_Application::resolveDynamicClass(__CLASS__);
return new $class($image);
}
/**
* Thumbnails the image.
*
* @see XenForo_Image_Abstract::thumbnail()
*/
public function thumbnail($maxWidth, $maxHeight = 0)
{
if ($maxWidth < 10)
{
$maxWidth = 10;
}
if ($maxHeight < 10)
{
$maxHeight = $maxWidth;
}
if ($this->_width < $maxWidth && $this->_height < $maxHeight)
{
return false;
}
$ratio = $this->_width / $this->_height;
$maxRatio = ($maxWidth / $maxHeight);
if ($maxRatio > $ratio)
{
$width = max(1, $maxHeight * $ratio);
$height = $maxHeight;
}
else
{
$width = $maxWidth;
$height = max(1, $maxWidth / $ratio);
}
$newImage = imagecreatetruecolor($width, $height);
$this->_preallocateBackground($newImage);
imagecopyresampled(
$newImage, $this->_image,
0, 0, 0, 0,
$width, $height, $this->_width, $this->_height
);
$this->_setImage($newImage);
return true;
}
/**
* Produces a thumbnail of the current image whose shorter side is the specified length
*
* @see XenForo_Image_Abstract::thumbnailFixedShorterSide
*/
public function thumbnailFixedShorterSide($shortSideLength)
{
if ($shortSideLength < 10)
{
$shortSideLength = 10;
}
$ratio = $this->_width / $this->_height;
if ($ratio > 1) // landscape
{
$width = $shortSideLength * $ratio;
$height = $shortSideLength;
}
else
{
$width = $shortSideLength;
$height = max(1, $shortSideLength / $ratio);
}
$newImage = imagecreatetruecolor($width, $height);
$this->_preallocateBackground($newImage);
imagecopyresampled(
$newImage, $this->_image,
0, 0, 0, 0,
$width, $height, $this->_width, $this->_height);
$this->_setImage($newImage);
}
/**
* Crops the image.
*
* @see XenForo_Image_Abstract::crop()
*/
public function crop($x, $y, $width, $height)
{
$newImage = imagecreatetruecolor($width, $height);
$this->_preallocateBackground($newImage);
imagecopyresampled(
$newImage, $this->_image,
0, 0, $x, $y,
$width, $height, $width, $height
);
$this->_setImage($newImage);
}
/**
* Rotates the image clockwise
*
* @see XenForo_Image_Abstract::rotate()
*/
public function rotate($angle)
{
$newImage = imagerotate($this->_image, $angle * -1, 0);
$this->_setImage($newImage);
}
/**
* Flips the image
*
* @see XenForo_Image_Abstract::flip()
*/
public function flip($mode)
{
$srcX = 0;
$srcY = 0;
$srcWidth = $this->_width;
$srcHeight = $this->_height;
switch ($mode)
{
case self::FLIP_HORIZONTAL:
$srcX = $this->_width - 1;
$srcWidth = -$this->_width;
break;
case self::FLIP_VERTICAL:
$srcY = $this->_height - 1;
$srcHeight = -$this->_height;
break;
case self::FLIP_BOTH:
$srcX = $this->_width - 1;
$srcWidth = -$this->_width;
$srcY = $this->_height - 1;
$srcHeight = -$this->_height;
break;
default:
return;
}
$newImage = imagecreatetruecolor($this->_width, $this->_height);
imagealphablending($newImage, false);
imagesavealpha($newImage, true);
imagecopyresampled(
$newImage, $this->_image,
0, 0, $srcX, $srcY,
$this->_width, $this->_height, $srcWidth, $srcHeight
);
$this->_setImage($newImage);
}
/**
* Outputs the image.
*
* @see XenForo_Image_Abstract::output()
*/
public function output($outputType, $outputFile = null, $quality = 85)
{
switch ($outputType)
{
case IMAGETYPE_GIF:
$success = imagegif($this->_image, $outputFile);
break;
case IMAGETYPE_JPEG: $success = imagejpeg($this->_image, $outputFile, $quality); break;
case IMAGETYPE_PNG:
imagealphablending($this->_image, false);
imagesavealpha($this->_image, true);
// "quality" seems to be misleading, always force 9
$success = imagepng($this->_image, $outputFile, 9, PNG_ALL_FILTERS);
break;
default:
throw new XenForo_Exception('Invalid output type given. Expects IMAGETYPE_XXX constant.');
}
return $success;
}
protected function _preallocateBackground($image)
{
imagesavealpha($image, true);
$color = imagecolorallocatealpha($image, 255, 255, 255, 127);
imagecolortransparent($image, $color);
imagefill($image, 0, 0, $color);
}
/**
* Sets the internal GD image resource.
*
* @param resource $image
*/
protected function _setImage($image)
{
$this->_image = $image;
$this->_width = imagesx($image);
$this->_height = imagesy($image);
}
}