Added "Core > Images > Add Below Annotation" demo

Author: JanSlabon

assets/pdfs/misc/link-annotation-placeholders.pdf

@@ -0,0 +1,9 @@
+{
+    "name": "Add Image Below Link Annotation",
+    "teaserText": "Add an image at the position of a link annotation.",
+    "requires": [
+        "SetaPDF-Core"
+    ],
+    "faIcon": "",
+    "faIcon2": ""
+}

public/demos/1-Core/images/5-add-below-annotation/demo.json

@@ -0,0 +1,4 @@
+<p>
+    This demo searches for link annotations on a page and places images on the found positions and removes the
+    link annotation afterwards.
+</p>

public/demos/1-Core/images/5-add-below-annotation/description.html

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+<?php
+
+// load and register the autoload function
+require_once '../../../../../bootstrap.php';
+
+$writer = new \SetaPDF_Core_Writer_Http('result.pdf', true);
+$document = \SetaPDF_Core_Document::loadByFilename(
+    $assetsDirectory . '/pdfs/misc/link-annotation-placeholders.pdf',
+    $writer
+);
+
+// let's prepare some kind of mapping
+$signatrues = [
+    'NameOfPersonX' => $assetsDirectory . '/images/Handwritten-Signature.png',
+    'NameOfPersonY' => $assetsDirectory . '/images/seal.png',
+];
+
+// get access to the pages object
+$pages = $document->getCatalog()->getPages();
+
+// get the first page
+$pageOne = $pages->getPage(1);
+
+// make sure that we have a clean graphic state
+$pageOne->getContents()->encapsulateExistingContentInGraphicState();
+
+// get the canvas
+$canvas = $pageOne->getCanvas();
+
+$annotations = $pageOne->getAnnotations();
+/** @var SetaPDF_Core_Document_Page_Annotation_Link[] $linkAnnotations */
+$linkAnnotations = $annotations->getAll(SetaPDF_Core_Document_Page_Annotation::TYPE_LINK);
+foreach ($linkAnnotations as $linkAnnotation) {
+    $action = $linkAnnotation->getAction();
+    if ($action instanceof SetaPDF_Core_Document_Action_Uri) {
+        // let's parse the uri/url and ensure some keys/values. The URLs in the example document look like:
+        // signature://yourDomain.com#nameOfPerson
+        $uri = parse_url($action->getUri());
+        if (
+            !is_array($uri)
+            || !isset($uri['scheme'], $uri['fragment'], $signatrues[$uri['fragment']])
+            || $uri['scheme'] !== 'signature'
+        ) {
+            continue;
+        }
+
+        $imgPath = $signatrues[$uri['fragment']];
+        $image = \SetaPDF_Core_Image::getByPath($imgPath)->toXObject($document);
+
+        // let's create a new XObject to scale/fit the signature image:
+        $rect = $linkAnnotation->getRect();
+        $height = $rect->getHeight();
+        $width = $rect->getWidth();
+        $xObject = SetaPDF_Core_XObject_Form::create($document, [0, 0, $width, $height]);
+        $xObjectCanvas = $xObject->getCanvas();
+
+        // fit the image into the size of the annotation
+        $maxWidth = $image->getWidth($height);
+        $maxHeight = $image->getHeight($width);
+
+        $x = 0;
+        $y = 0;
+        if ($maxHeight > $height) {
+            $x += $width / 2 - $maxWidth / 2;
+            $image->draw($xObjectCanvas, $x, $y, null, $height);
+        } else {
+            $y += $height / 2 - $maxHeight / 2;
+            $image->draw($xObjectCanvas, $x, $y, $width, null);
+        }
+
+        // draw the new xObject onto the main canvas
+        $xObject->draw($canvas, $rect->llx, $rect->lly);
+
+        // ...and remove the annotation
+        $annotations->remove($linkAnnotation);
+    }
+}
+
+// save and finish
+$document->save()->finish();