1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 var backImageCanvas; 6 7 function prepareBackground() { 8 var backImage = document.getElementById('backImage'); 9 backImageCanvas = document.createElement('canvas'); 10 backImageCanvas.width = backImage.naturalWidth; 11 backImageCanvas.height = backImage.naturalHeight; 12 var backContext = backImageCanvas.getContext('2d'); 13 backContext.drawImage(backImage, 0, 0); 14 } 15 16 function drawBackground() { 17 canvasContext.drawImage(backImageCanvas, 0, 0, canvasWidth, canvasHeight); 18 } 19
