Added QR Code Scanner Extension

scratch.qr.code.scanner.js

@@ -0,0 +1,112 @@
+(function(Scratch) {
+  'use strict';
+
+  // Load the jsQR library dynamically from a CDN
+  const script = document.createElement('script');
+  script.src = 'https://cdn.jsdelivr.net/npm/[email protected]/dist/jsQR.min.js';
+  document.head.appendChild(script);
+
+  class QRCodeScanner {
+    constructor() {
+      this.lastResult = null;
+      this.detected = false;
+      this.isScanning = false;
+    }
+
+    getInfo() {
+      return {
+        id: 'sweetsebiQR',
+        name: 'QR Scanner',
+        color1: '#4C97FF',
+        color2: '#3373CC',
+        blocks: [
+          {
+            opcode: 'scanScreen',
+            blockType: Scratch.BlockType.COMMAND,
+            text: Scratch.translate('scan screen for QR code')
+          },
+          {
+            opcode: 'isDetected',
+            blockType: Scratch.BlockType.BOOLEAN,
+            text: Scratch.translate('is a QR code detected?')
+          },
+          {
+            opcode: 'getData',
+            blockType: Scratch.BlockType.REPORTER,
+            text: Scratch.translate('QR code data')
+          }
+        ]
+      };
+    }
+
+    /**
+     * Captures the stage using a more robust "frame capture" method.
+     */
+    scanScreen() {
+      if (typeof jsQR === 'undefined') {
+        console.warn('QR Scanner: jsQR library not loaded yet.');
+        return;
+      }
+
+      if (this.isScanning) return;
+      this.isScanning = true;
+
+      const runtime = Scratch.vm.runtime;
+      const renderer = runtime.renderer;
+
+      if (!renderer || !renderer.canvas) {
+        console.error('QR Scanner: Renderer or Canvas not found.');
+        this.isScanning = false;
+        return;
+      }
+
+      try {
+        const canvas = renderer.canvas;
+        const width = canvas.width;
+        const height = canvas.height;
+
+        // Create the off-screen canvas once
+        const snapshotCanvas = document.createElement('canvas');
+        snapshotCanvas.width = width;
+        snapshotCanvas.height = height;
+        const ctx = snapshotCanvas.getContext('2d');
+
+        // FORCE A RENDER: TurboWarp's canvas is often empty between frames.
+        // We tell the renderer to draw exactly now so the buffer is full.
+        renderer.draw(); 
+
+        // Grab the content immediately after the draw call
+        ctx.drawImage(canvas, 0, 0);
+
+        const imageData = ctx.getImageData(0, 0, width, height);
+
+        // Scan the pixels
+        const code = jsQR(imageData.data, width, height, {
+          inversionAttempts: "dontInvert"
+        });
+
+        if (code && code.data) {
+          this.lastResult = code.data;
+          this.detected = true;
+        } else {
+          this.detected = false;
+        }
+      } catch (e) {
+        console.error('QR Scanner Error:', e);
+        this.detected = false;
+      }
+
+      this.isScanning = false;
+    }
+
+    isDetected() {
+      return this.detected;
+    }
+
+    getData() {
+      return this.detected ? this.lastResult : "";
+    }
+  }
+
+  Scratch.extensions.register(new QRCodeScanner());
+})(Scratch);