deb-novnc/include/util.js
Joel Martin 9e01c5701e canvas.js: workaround WebKit bug, issue #28.
This is WebKit bug https://bugs.webkit.org/show_bug.cgi?id=46319

The workaround is to wrap Canvas render functions with a function that
sets a flush timer. The flush function sets the right margin and then
1ms later sets it back. This triggers the canvas to redraw with the
correct contents.

Two downsides:
- rendering is slower, but only on the busted versions of webkit.
  Correct and useful is better than fast and useless.
- There is a barely perceptible jitter of the control buttons because
  the canvas size is changing by one pixel.

To support this functionality, we also have to read out the exact
webkit version from the user agent in the render engine detection code
in include/util.js.
2010-11-06 12:23:23 -05:00

234 lines
7.0 KiB
JavaScript

/*
* noVNC: HTML5 VNC client
* Copyright (C) 2010 Joel Martin
* Licensed under LGPL-3 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*/
"use strict";
/*jslint bitwise: false, white: false */
/*global window, console, document, navigator, ActiveXObject */
// Globals defined here
var Util = {};
/*
* Make arrays quack
*/
Array.prototype.push8 = function (num) {
this.push(num & 0xFF);
};
Array.prototype.push16 = function (num) {
this.push((num >> 8) & 0xFF,
(num ) & 0xFF );
};
Array.prototype.push32 = function (num) {
this.push((num >> 24) & 0xFF,
(num >> 16) & 0xFF,
(num >> 8) & 0xFF,
(num ) & 0xFF );
};
/*
* ------------------------------------------------------
* Namespaced in Util
* ------------------------------------------------------
*/
/*
* Logging/debug routines
*/
Util._log_level = 'warn';
Util.init_logging = function (level) {
if (typeof level === 'undefined') {
level = Util._log_level;
} else {
Util._log_level = level;
}
if (typeof window.console === "undefined") {
if (typeof window.opera !== "undefined") {
window.console = {
'log' : window.opera.postError,
'warn' : window.opera.postError,
'error': window.opera.postError };
} else {
window.console = {
'log' : function(m) {},
'warn' : function(m) {},
'error': function(m) {}};
}
}
Util.Debug = Util.Info = Util.Warn = Util.Error = function (msg) {};
switch (level) {
case 'debug': Util.Debug = function (msg) { console.log(msg); };
case 'info': Util.Info = function (msg) { console.log(msg); };
case 'warn': Util.Warn = function (msg) { console.warn(msg); };
case 'error': Util.Error = function (msg) { console.error(msg); };
case 'none':
break;
default:
throw("invalid logging type '" + level + "'");
}
};
Util.get_logging = function () {
return Util._log_level;
}
// Initialize logging level
Util.init_logging();
// Set defaults for Crockford style function namespaces
Util.conf_default = function(cfg, api, v, type, defval, desc) {
// Description
api['get_' + v + '_desc'] = desc;
// Default getter
if (typeof api['get_' + v] === 'undefined') {
api['get_' + v] = function () {
return cfg[v];
};
}
// Default setter
if (typeof api['set_' + v] === 'undefined') {
api['set_' + v] = function (val) {
if (type in {'boolean':1, 'bool':1}) {
if ((!val) || (val in {'0':1, 'no':1, 'false':1})) {
val = false;
} else {
val = true;
}
} else if (type in {'integer':1, 'int':1}) {
val = parseInt(val, 10);
}
cfg[v] = val;
};
}
if (typeof cfg[v] === 'undefined') {
// Set to default
api['set_' + v](defval);
} else {
// Coerce existing setting to the right type
api['set_' + v](cfg[v]);
}
};
/*
* Cross-browser routines
*/
// Get DOM element position on page
Util.getPosition = function (obj) {
var x = 0, y = 0;
if (obj.offsetParent) {
do {
x += obj.offsetLeft;
y += obj.offsetTop;
obj = obj.offsetParent;
} while (obj);
}
return {'x': x, 'y': y};
};
// Get mouse event position in DOM element
Util.getEventPosition = function (e, obj, scale) {
var evt, docX, docY, pos;
//if (!e) evt = window.event;
evt = (e ? e : window.event);
if (evt.pageX || evt.pageY) {
docX = evt.pageX;
docY = evt.pageY;
} else if (evt.clientX || evt.clientY) {
docX = evt.clientX + document.body.scrollLeft +
document.documentElement.scrollLeft;
docY = evt.clientY + document.body.scrollTop +
document.documentElement.scrollTop;
}
pos = Util.getPosition(obj);
if (typeof scale === "undefined") {
scale = 1;
}
return {'x': (docX - pos.x) / scale, 'y': (docY - pos.y) / scale};
};
// Event registration. Based on: http://www.scottandrew.com/weblog/articles/cbs-events
Util.addEvent = function (obj, evType, fn){
if (obj.attachEvent){
var r = obj.attachEvent("on"+evType, fn);
return r;
} else if (obj.addEventListener){
obj.addEventListener(evType, fn, false);
return true;
} else {
throw("Handler could not be attached");
}
};
Util.removeEvent = function(obj, evType, fn){
if (obj.detachEvent){
var r = obj.detachEvent("on"+evType, fn);
return r;
} else if (obj.removeEventListener){
obj.removeEventListener(evType, fn, false);
return true;
} else {
throw("Handler could not be removed");
}
};
Util.stopEvent = function(e) {
if (e.stopPropagation) { e.stopPropagation(); }
else { e.cancelBubble = true; }
if (e.preventDefault) { e.preventDefault(); }
else { e.returnValue = false; }
};
// Set browser engine versions. Based on mootools.
Util.Features = {xpath: !!(document.evaluate), air: !!(window.runtime), query: !!(document.querySelector)};
Util.Engine = {
'presto': (function() {
return (!window.opera) ? false : ((arguments.callee.caller) ? 960 : ((document.getElementsByClassName) ? 950 : 925)); }()),
'trident': (function() {
return (!window.ActiveXObject) ? false : ((window.XMLHttpRequest) ? ((document.querySelectorAll) ? 6 : 5) : 4); }()),
'webkit': (function() {
try { return (navigator.taintEnabled) ? false : ((Util.Features.xpath) ? ((Util.Features.query) ? 525 : 420) : 419); } catch (e) { return false; } }()),
//'webkit': (function() {
// return ((typeof navigator.taintEnabled !== "unknown") && navigator.taintEnabled) ? false : ((Util.Features.xpath) ? ((Util.Features.query) ? 525 : 420) : 419); }()),
'gecko': (function() {
return (!document.getBoxObjectFor && window.mozInnerScreenX == null) ? false : ((document.getElementsByClassName) ? 19 : 18); }())
};
if (Util.Engine.webkit) {
// Extract actual webkit version if available
Util.Engine.webkit = (function(v) {
var re = new RegExp('WebKit/([0-9\.]*) ');
v = (navigator.userAgent.match(re) || ['', v])[1];
return parseFloat(v, 10);
})(Util.Engine.webkit);
}
Util.Flash = (function(){
var v, version;
try {
v = navigator.plugins['Shockwave Flash'].description;
} catch(err1) {
try {
v = new ActiveXObject('ShockwaveFlash.ShockwaveFlash').GetVariable('$version');
} catch(err2) {
v = '0 r0';
}
}
version = v.match(/\d+/g);
return {version: parseInt(version[0] || 0 + '.' + version[1], 10) || 0, build: parseInt(version[2], 10) || 0};
}());