From: Matthias Schmidt <gravatronics@live.com>
Date: Mon, 22 Dec 2014 09:58:12 +0000 (+0100)
Subject: Add API to overlay image
X-Git-Tag: 2.1.0_Beta_3~96^2~4
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a7c0248c576332e3317e1310f06481693d95b866;p=GitHub%2FWoltLab%2FWCF.git

Add API to overlay image
---

diff --git a/wcfsetup/install/files/lib/system/image/adapter/GDImageAdapter.class.php b/wcfsetup/install/files/lib/system/image/adapter/GDImageAdapter.class.php
index 132acaa03e..f4420e30d1 100644
--- a/wcfsetup/install/files/lib/system/image/adapter/GDImageAdapter.class.php
+++ b/wcfsetup/install/files/lib/system/image/adapter/GDImageAdapter.class.php
@@ -276,6 +276,28 @@ class GDImageAdapter implements IImageAdapter {
 		return imagerotate($this->image, (360.0 - $degrees), ($this->color ?: 0));
 	}
 	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImage()
+	 */
+	public function overlayImage($file, $x, $y, $opacity) {
+		$overlayImage = new self();
+		$overlayImage->loadFile($file);
+		
+		// fix PNG alpha channel handling
+		// see http://php.net/manual/en/function.imagecopymerge.php#92787
+		$cut = imagecreatetruecolor($overlayImage->getWidth(), $overlayImage->getHeight());
+		imagecopy($cut, $this->image, 0, 0, $x, $y, $overlayImage->getWidth(), $overlayImage->getHeight());
+		imagecopy($cut, $overlayImage->image, 0, 0, 0, 0, $overlayImage->getWidth(), $overlayImage->getHeight());
+		imagecopymerge($this->image, $cut, $x, $y, 0, 0, $overlayImage->getWidth(), $overlayImage->getHeight(), $opacity * 100);
+	}
+	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImageRelative()
+	 */
+	public function overlayImageRelative($file, $position, $margin, $opacity) {
+		// does nothing
+	}
+	
 	/**
 	 * @see	\wcf\system\image\adapter\IImageAdapter::isSupported()
 	 */
diff --git a/wcfsetup/install/files/lib/system/image/adapter/IImageAdapter.class.php b/wcfsetup/install/files/lib/system/image/adapter/IImageAdapter.class.php
index c97345cad3..aaa0670dcc 100644
--- a/wcfsetup/install/files/lib/system/image/adapter/IImageAdapter.class.php
+++ b/wcfsetup/install/files/lib/system/image/adapter/IImageAdapter.class.php
@@ -161,6 +161,26 @@ interface IImageAdapter {
 	 */
 	public function rotate($degrees);
 	
+	/**
+	 * Overlays the given image at an absolute position.
+	 * 
+	 * @param	string		$file
+	 * @param	integer		$x
+	 * @param	integer		$y
+	 * @param	float		$opacity
+	 */
+	public function overlayImage($file, $x, $y, $opacity);
+	
+	/**
+	 * Overlays the given image at a relative position.
+	 * 
+	 * @param	string		$file
+	 * @param	string		$position
+	 * @param	integer		$margin
+	 * @param	float		$opacity
+	 */
+	public function overlayImageRelative($file, $position, $margin, $opacity);
+	
 	/**
 	 * Determines if an image adapter is supported.
 	 * 
diff --git a/wcfsetup/install/files/lib/system/image/adapter/ImageAdapter.class.php b/wcfsetup/install/files/lib/system/image/adapter/ImageAdapter.class.php
index d5daca8834..0433dac0e2 100644
--- a/wcfsetup/install/files/lib/system/image/adapter/ImageAdapter.class.php
+++ b/wcfsetup/install/files/lib/system/image/adapter/ImageAdapter.class.php
@@ -19,6 +19,22 @@ class ImageAdapter implements IImageAdapter {
 	 */
 	protected $adapter = null;
 	
+	/**
+	 * supported relative positions
+	 * @var	array<string>
+	 */
+	protected $relativePositions = array(
+		'topLeft',
+		'topCenter',
+		'topRight',
+		'middleLeft',
+		'middleCenter',
+		'middleRight',
+		'bottomLeft',
+		'bottomCenter',
+		'bottomRight'
+	);
+	
 	/**
 	 * Creates a new ImageAdapter instance.
 	 * 
@@ -192,6 +208,90 @@ class ImageAdapter implements IImageAdapter {
 		return $this->adapter->rotate($degrees);
 	}
 	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImage()
+	 */
+	public function overlayImage($file, $x, $y, $opacity) {
+		// validate file
+		if (!file_exists($file)) {
+			throw new SystemException("Image '".$file."' does not exist.");
+		}
+		
+		$this->adapter->overlayImage($file, $x, $y, $opacity);
+	}
+	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImage()
+	 */
+	public function overlayImageRelative($file, $position, $margin, $opacity) {
+		// validate file
+		if (!file_exists($file)) {
+			throw new SystemException("Image '".$file."' does not exist.");
+		}
+		
+		// validate position
+		if (!in_array($position, $this->relativePositions)) {
+			throw new SystemException("Unknown relative position '".$position."'.");
+		}
+		
+		// validate margin
+		if ($margin < 0 || $margin >= $this->getHeight() / 2 || $margin >= $this->getWidth() / 2) {
+			throw new SystemException("Margin has to be positive and respect image dimensions.");
+		}
+		
+		$adapterClassName = get_class($this->adapter);
+		$overlayImage = new $adapterClassName();
+		$overlayImage->loadFile($file);
+		$overlayHeight = $overlayImage->getHeight();
+		$overlayWidth = $overlayImage->getWidth();
+		
+		// calculate y coordinate
+		$x = 0;
+		switch ($position) {
+			case 'topLeft':
+			case 'middleLeft':
+			case 'bottomLeft':
+				$x = $margin;
+			break;
+			
+			case 'topCenter':
+			case 'middleCenter':
+			case 'bottomCenter':
+				$x = floor(($this->getWidth() - $overlayWidth) / 2);
+			break;
+			
+			case 'topRight':
+			case 'middleRight':
+			case 'bottomRight':
+				$x = $this->getWidth() - $overlayWidth - $margin;
+			break;
+		}
+		
+		// calculate y coordinate
+		$y = 0;
+		switch ($position) {
+			case 'topLeft':
+			case 'topCenter':
+			case 'topRight':
+				$y = $margin;
+			break;
+			
+			case 'middleLeft':
+			case 'middleCenter':
+			case 'middleRight':
+				$y = floor(($this->getHeight() - $overlayHeight) / 2);
+			break;
+			
+			case 'bottomLeft':
+			case 'bottomCenter':
+			case 'bottomRight':
+				$y = $this->getHeight() - $overlayHeight - $margin;
+			break;
+		}
+		
+		$this->overlayImage($file, $x, $y, $opacity);
+	}
+	
 	/**
 	 * @see	\wcf\system\image\adapter\IImageAdapter::isSupported()
 	 */
diff --git a/wcfsetup/install/files/lib/system/image/adapter/ImagickImageAdapter.class.php b/wcfsetup/install/files/lib/system/image/adapter/ImagickImageAdapter.class.php
index da7b7f6c33..42b3eaacb8 100644
--- a/wcfsetup/install/files/lib/system/image/adapter/ImagickImageAdapter.class.php
+++ b/wcfsetup/install/files/lib/system/image/adapter/ImagickImageAdapter.class.php
@@ -76,6 +76,7 @@ class ImagickImageAdapter implements IImageAdapter {
 	 */
 	public function loadFile($file) {
 		try {
+			$this->imagick->clear();
 			$this->imagick->readImage($file);
 		}
 		catch (\ImagickException $e) {
@@ -280,6 +281,29 @@ class ImagickImageAdapter implements IImageAdapter {
 		return $image;
 	}
 	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImage()
+	 */
+	public function overlayImage($file, $x, $y, $opacity) {
+		try {
+			$overlayImage = new \Imagick($file);
+		}
+		catch (\ImagickException $e) {
+			throw new SystemException("Image '".$file."' is not readable or does not exist.");
+		}
+		
+		$overlayImage->evaluateImage(\Imagick::EVALUATE_MULTIPLY, $opacity, \Imagick::CHANNEL_OPACITY);
+		$this->imagick->compositeImage($overlayImage, \Imagick::COMPOSITE_OVER, $x, $y);
+		$this->imagick = $this->imagick->flattenImages();
+	}
+	
+	/**
+	 * @see	\wcf\system\image\adapter\IImageAdapter::overlayImageRelative()
+	 */
+	public function overlayImageRelative($file, $position, $margin, $opacity) {
+		// does nothing
+	}
+	
 	/**
 	 * @see	\wcf\system\image\adapter\IImageAdapter::isSupported()
 	 */