Łatwe tworzenie "watermark" / dodawanie loga w PhpThumb by gxdlabs

• 

  Nasz watermark

• 

  Efekt działania

W folderze biblioteki PhpThumb odszukujemy folder "thumb_plugins"

Tworzymy w nim plik o nazwie "gd_GdAddLogo_inc.php"

• //sensu stricte nazwa może być dowolna.

Wewnątrz zapisujemy:

<?php
/**
 * Add logo plugin
 * 
 * This plugin allows you to add plugin to your image
 * 
 * @package PhpThumb
 * @subpackage Plugins
 * @original-author Sergey "hssergey"
 * @author Sebastian "DNightmare"
 */
class GdAddLogo {
    /**
     * Instance of GdThumb passed to this class
     * 
     * @var GdThumb
     */
    protected $parentInstance;
    protected $currentDimensions;
    protected $workingImage;
    protected $newImage;
    protected $options;

    /**
     * Add logo to image
     * @param logoFileName - file name of logo image in jpg or png format
     * @param positionX - Position of logo image on X-axis ('left', 'center', 'right' or plain number)
     * @param positionY - Position of logo image on X-axis ('top', 'center', 'bottom' or plain number)
     * @param alpha - alpha value for logo merging in percent
     */
    public function addLogo($logoFileName, $positionX, $positionY, $alpha, &$that) {
        $logo_size                  = getimagesize($logoFileName);
        // bring stuff from the parent class into this class...
        $this->parentInstance       = $that;
        $this->oldImage             = $this->parentInstance->getOldImage();
        $this->parentInstance->setWorkingImage($this->oldImage);
        $this->currentDimensions    = $this->parentInstance->getCurrentDimensions();
        $this->workingImage         = $this->parentInstance->getWorkingImage();
        $this->options              = $this->parentInstance->getOptions();

        $src_dimension              = array(
                                        "x" => $this->currentDimensions['width'], 
                                        "y" => $this->currentDimensions['height']);
        $logo_dimension             = array(
                                        "x" => $logo_size[0],
                                        "y" => $logo_size[1]);

        $center                     = array(
                                        "x" => (($src_dimension["x"] / 2) - ($logo_dimension["x"]/2)),
                                        "y" => (($src_dimension["y"] / 2) - ($logo_dimension["y"]/2)));

        $logo_postionX["left"]      = 0;
        $logo_postionX["center"]    = $center["x"];
        $logo_postionX["right"]     = $src_dimension["x"] - $logo_dimension["x"];
        $logo_postionY["top"]       = 0;
        $logo_postionY["center"]    = $center["y"];
        $logo_postionY["bottom"]    = $src_dimension["y"] - $logo_dimension["y"];

        if(is_numeric($positionX)){ $logo_position["x"] = $positionX; } else { $logo_position["x"] = $logo_postionX[$positionX]; }
        if(is_numeric($positionY)){ $logo_position["y"] = $positionY; } else { $logo_position["y"] = $logo_postionY[$positionY]; }

        switch(exif_imagetype($logoFileName)){
            case IMAGETYPE_JPEG:
                $logo = imagecreatefromjpeg($logoFileName);
                break;
            case IMAGETYPE_PNG:
                $logo = imagecreatefrompng($logoFileName);
                break;
        }

        imagecopy($this->workingImage, $logo, $logo_position["x"], $logo_position["y"], 0, 0, $logo_dimension["x"], $logo_dimension["y"]);
        return $that;
    }
}
$pt = PhpThumb::getInstance();
$pt->registerPlugin('GdAddLogo', 'gd');
</source>

Następnie tworzymy stronę testową:

$thumb = PhpThumbFactory::create($xxx);
// Logo at top-center position 25% visible
$thumb->addLogo("./phpthumb_biblioteka/watermark.png", 'right', 'bottom', 100);
// Logo at bottom position, 100px from the left side 10% visible
// $thumb->addLogo($_SERVER["DOCUMENT_ROOT"]."/images/imageForLogo.png", 'top', 100, 10);
$thumb->show();
</source>

$xxx - to ścieżka do obrazka.



Uwaga:
Oryginalny skrypt został opublikowany pod adresem :

https://github.com/masterexploder/PHPThumb/issues/34

przez użytkownika:

 DNightmare commented May 30, 2011

w kodzie powyżej zmieniona została metoda przez nas 
imagemerege na imagecopy w celu zachowania przeźroczystości.