Added "Core > Canvas > Add crop marks" demo

public/demos/1-Core/canvas/add-crop-marks/demo.json

@@ -0,0 +1,8 @@
+{
+    "name": "Add Crop Marks",
+    "teaserText": "Update the page boundaries and add some crop marks to an existing PDF page.",
+    "requires": [
+        "SetaPDF-Core"
+    ],
+    "faIcon": ""
+}

public/demos/1-Core/canvas/add-crop-marks/script.php

@@ -0,0 +1,66 @@
+<?php
+
+// load and register the autoload function
+require_once '../../../../../bootstrap.php';
+
+// create a writer instance
+$writer = new \SetaPDF_Core_Writer_Http('with-crop-marks.pdf', true);
+
+// create a document instance
+$document = SetaPDF_Core_Document::loadByFilename($assetsDirectory . '/pdfs/camtown/Business-Card-filled.pdf', $writer);
+
+$pages = $document->getCatalog()->getPages();
+
+$mm = 2;
+$points = $mm * 2.8346456693; // 2mm to Points
+
+// get the page object
+$page = $pages->getPage(1);
+
+// let's save the main TrimBox
+$trimBox = $page->getTrimBox();
+
+// get the MediaBox and enlarge it
+$box = $page->getMediaBox();
+$box->setLlx($box->getLlx() - $points);
+$box->setLly($box->getLly() - $points);
+$box->setUrx($box->getUrx() + $points);
+$box->setUry($box->getUry() + $points);
+
+// set the new box as both Media- and CropBox
+$page->setMediaBox($box);
+$page->setCropBox($box);
+
+// now set a reduced TrimBox
+$trimBox->setLlx($trimBox->getLlx() + $points);
+$trimBox->setLly($trimBox->getLly() + $points);
+$trimBox->setUrx($trimBox->getUrx() - $points);
+$trimBox->setUry($trimBox->getUry() - $points);
+$page->setTrimBox($trimBox);
+
+// make sure we have a clean graphic state
+$page->getStreamProxy()->encapsulateExistingContentInGraphicState();
+// get the canvas...
+$canvas = $page->getCanvas();
+
+// and draw the crop marks - we use values of both boundary boxes
+$canvas->saveGraphicState()
+    ->path()
+    ->setLineWidth(.1)
+    ->setStrokingColor(.3)
+    ->draw()
+    // left-top
+    ->line($box->getLlx(), $trimBox->getUry(), $trimBox->getLlx() - $points / 2, $trimBox->getUry())
+    ->line($trimBox->getLlx(), $box->getUry(), $trimBox->getLlx(), $trimBox->getUry() + $points / 2)
+    // right-top
+    ->line($trimBox->getUrx(), $box->getUry(), $trimBox->getUrx(), $trimBox->getUry() + $points / 2)
+    ->line($trimBox->getUrx() + $points / 2, $trimBox->getUry(), $box->getUrx(), $trimBox->getUry())
+    // right-bottom
+    ->line($box->getUrx(), $trimBox->getLly(), $trimBox->getUrx() + $points / 2, $trimBox->getLly())
+    ->line($trimBox->getUrx(), $box->getLly(), $trimBox->getUrx(), $trimBox->getLly() - $points / 2)
+    // left-bottom
+    ->line($trimBox->getLlx(), $box->getLly(), $trimBox->getLlx(), $trimBox->getLly() - $points / 2)
+    ->line($box->getLlx(), $trimBox->getLly(), $trimBox->getLlx() - $points / 2, $trimBox->getLly())
+    ->restoreGraphicState();
+
+$document->save()->finish();