From 54fb1f7226a897fdebca7c8d9ea8eab15b0ea359 Mon Sep 17 00:00:00 2001
From: Fabian Lange <lange.fabian@gmail.com>
Date: Wed, 25 Jun 2014 12:52:06 +0200
Subject: [PATCH] Improving CanvasPixelArray polyfill for Android
---
web/compatibility.js | 42 ++++++++++++++++++++++++++++--------------
1 file changed, 28 insertions(+), 14 deletions(-)
diff --git a/web/compatibility.js b/web/compatibility.js
index 3bb437780..73f78825f 100644
--- a/web/compatibility.js
+++ b/web/compatibility.js
@@ -481,7 +481,7 @@ if (typeof PDFJS === 'undefined') {
}
})();
-// Support: IE<11, Chrome<21
+// Support: IE<11, Chrome<21, Android<4.4
(function checkSetPresenceInImageData() {
// IE < 11 will use window.CanvasPixelArray which lacks set function.
if (window.CanvasPixelArray) {
@@ -493,23 +493,37 @@ if (typeof PDFJS === 'undefined') {
};
}
} else {
- // Chrome < 21 uses an inaccessible CanvasPixelArray prototype.
- // Because we cannot feature detect it, we rely on user agent.
+ // Old Chrome and Android use an inaccessible CanvasPixelArray prototype.
+ // Because we cannot feature detect it, we rely on user agent parsing.
+ var polyfill = false;
if (navigator.userAgent.indexOf('Chrom') >= 0) {
var versionMatch = navigator.userAgent.match(/Chrom(e|ium)\/([0-9]+)\./);
if (versionMatch && parseInt(versionMatch[2]) < 21) {
- var contextPrototype = window.CanvasRenderingContext2D.prototype;
- contextPrototype._createImageData = contextPrototype.createImageData;
- contextPrototype.createImageData = function(w, h) {
- var imageData = this._createImageData(w, h);
- imageData.data.set = function(arr) {
- for (var i = 0, ii = this.length; i < ii; i++) {
- this[i] = arr[i];
- }
- };
- return imageData;
- };
+ // Chrome < 21 lacks the set function.
+ polyfill = true;
}
+ } else if (navigator.userAgent.indexOf('Android') >= 0) {
+ // Android < 4.4 lacks the set function.
+ // Android >= 4.4 will contain Chrome in the user agent,
+ // thus pass the Chrome check above and not reach this block.
+ var isOldAndroid = /Android\s[0-4][^\d]/g.test(navigator.userAgent);
+ if (isOldAndroid) {
+ polyfill = true;
+ }
+ }
+
+ if (polyfill) {
+ var contextPrototype = window.CanvasRenderingContext2D.prototype;
+ contextPrototype._createImageData = contextPrototype.createImageData;
+ contextPrototype.createImageData = function(w, h) {
+ var imageData = this._createImageData(w, h);
+ imageData.data.set = function(arr) {
+ for (var i = 0, ii = this.length; i < ii; i++) {
+ this[i] = arr[i];
+ }
+ };
+ return imageData;
+ };
}
}
})();