Solution:
// Copyright 2006 Google Inc.
//tiny fix by Veerman Internet Services to allow initialization on HTML
loaded after document.ready
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Known Issues:
//
// * Patterns are not implemented.
// * Radial gradient are not implemented. The VML version of these look very
// different from the canvas one.
// * Clipping paths are not implemented.
// * Coordsize. The width and height attribute have higher priority than the
// width and height style values which isn't correct.
// * Painting mode isn't implemented.
// * Canvas width/height should is using content-box by default. IE in
// Quirks mode will draw the canvas using border-box. Either change your
// doctype to HTML5
// (http://www.whatwg.org/specs/web-apps/current-work/#the-doctype)
// or use Box Sizing Behavior from WebFX
// (http://webfx.eae.net/dhtml/boxsizing/boxsizing.html)
// * Optimize. There is always room for speed improvements.
// only add this code if we do not already have a canvas implementation
if (!window.CanvasRenderingContext2D) {
var googleExCanvas = function(){
// alias some functions to make (compiled) code shorter
var m = Math;
var mr = m.round;
var ms = m.sin;
var mc = m.cos;
// this is used for sub pixel precision
var Z = 10;
var Z2 = Z / 2;
var G_vmlCanvasManager_ = {
init: function(opt_doc){
var doc = opt_doc || document;
if (/MSIE/.test(navigator.userAgent) && !window.opera) {
var self = this;
// doc.attachEvent("onreadystatechange", function(){
self.init_(doc);
// });
}
},
init_: function(doc){
if (doc.readyState == "complete") {
// create xmlns
if (!doc.namespaces["g_vml_"]) {
doc.namespaces.add("g_vml_",
"urn:schemas-microsoft-com:vml");
}
// setup default css
var ss = doc.createStyleSheet();
ss.cssText =
"canvas{display:inline-block;overflow:hidden;" +
// default size is 300x150 in Gecko and Opera
"text-align:left;width:300px;height:150px}" +
"g_vml_\\:*{behavior:url(#default#VML)}";
// find all canvas elements
var els = doc.getElementsByTagName("canvas");
for (var i = 0; i < els.length; i++) {
if (!els[i].getContext) {
this.initElement(els[i]);
}
}
}
},
fixElement_: function(el){
// in IE before version 5.5 we would need to add HTML: to
the tag name
// but we do not care about IE before version 6
var outerHTML = el.outerHTML;
var newEl = el.ownerDocument.createElement(outerHTML);
// if the tag is still open IE has created the children as
siblings and
// it has also created a tag with the name "/FOO"
if (outerHTML.slice(-2) != "/>") {
var tagName = "/" + el.tagName;
var ns;
// remove content
while ((ns = el.nextSibling) && ns.tagName != tagName) {
ns.removeNode();
}
// remove the incorrect closing tag
if (ns) {
ns.removeNode();
}
}
el.parentNode.replaceChild(newEl, el);
return newEl;
},
/**
* Public initializes a canvas element so that it can be used as
canvas
* element from now on. This is called automatically before the
page is
* loaded but if you are creating elements using createElement
you need to
* make sure this is called on the element.
* @param {HTMLElement} el The canvas element to initialize.
* @return {HTMLElement} the element that was created.
*/
initElement: function(el){
el = this.fixElement_(el);
el.getContext = function(){
if (this.context_) {
return this.context_;
}
return this.context_ = new CanvasRenderingContext2D_(this);
};
// do not use inline function because that will leak memory
el.attachEvent('onpropertychange', onPropertyChange);
el.attachEvent('onresize', onResize);
var attrs = el.attributes;
if (attrs.width && attrs.width.specified) {
// TODO: use runtimeStyle and coordsize
// el.getContext().setWidth_(attrs.width.nodeValue);
el.style.width = attrs.width.nodeValue + "px";
}
else {
el.width = el.clientWidth;
}
if (attrs.height && attrs.height.specified) {
// TODO: use runtimeStyle and coordsize
// el.getContext().setHeight_(attrs.height.nodeValue);
el.style.height = attrs.height.nodeValue + "px";
}
else {
el.height = el.clientHeight;
}
//el.getContext().setCoordsize_()
return el;
}
};
function onPropertyChange(e){
var el = e.srcElement;
switch (e.propertyName) {
case 'width':
el.style.width = el.attributes.width.nodeValue + "px";
el.getContext().clearRect();
break;
case 'height':
el.style.height = el.attributes.height.nodeValue + "px";
el.getContext().clearRect();
break;
}
}
function onResize(e){
var el = e.srcElement;
if (el.firstChild) {
el.firstChild.style.width = el.clientWidth + 'px';
el.firstChild.style.height = el.clientHeight + 'px';
}
}
G_vmlCanvasManager_.init();
// precompute "00" to "FF"
var dec2hex = [];
for (var i = 0; i < 16; i++) {
for (var j = 0; j < 16; j++) {
dec2hex[i * 16 + j] = i.toString(16) + j.toString(16);
}
}
function createMatrixIdentity(){
return [[1, 0, 0], [0, 1, 0], [0, 0, 1]];
}
function matrixMultiply(m1, m2){
var result = createMatrixIdentity();
for (var x = 0; x < 3; x++) {
for (var y = 0; y < 3; y++) {
var sum = 0;
for (var z = 0; z < 3; z++) {
sum += m1[x][z] * m2[z][y];
}
result[x][y] = sum;
}
}
return result;
}
function copyState(o1, o2){
o2.fillStyle = o1.fillStyle;
o2.lineCap = o1.lineCap;
o2.lineJoin = o1.lineJoin;
o2.lineWidth = o1.lineWidth;
o2.miterLimit = o1.miterLimit;
o2.shadowBlur = o1.shadowBlur;
o2.shadowColor = o1.shadowColor;
o2.shadowOffsetX = o1.shadowOffsetX;
o2.shadowOffsetY = o1.shadowOffsetY;
o2.strokeStyle = o1.strokeStyle;
o2.arcScaleX_ = o1.arcScaleX_;
o2.arcScaleY_ = o1.arcScaleY_;
}
function processStyle(styleString){
var str, alpha = 1;
styleString = String(styleString);
if (styleString.substring(0, 3) == "rgb") {
var start = styleString.indexOf("(", 3);
var end = styleString.indexOf(")", start + 1);
var guts = styleString.substring(start + 1, end).split(",");
str = "#";
for (var i = 0; i < 3; i++) {
str += dec2hex[Number(guts[i])];
}
if ((guts.length == 4) && (styleString.substr(3, 1) == "a")) {
alpha = guts[3];
}
}
else {
str = styleString;
}
return [str, alpha];
}
function processLineCap(lineCap){
switch (lineCap) {
case "butt":
return "flat";
case "round":
return "round";
case "square":
default:
return "square";
}
}
/**
* This class implements CanvasRenderingContext2D interface as
described by
* the WHATWG.
* @param {HTMLElement} surfaceElement The element that the 2D
context should
* be associated with
*/
function CanvasRenderingContext2D_(surfaceElement){
this.m_ = createMatrixIdentity();
this.mStack_ = [];
this.aStack_ = [];
this.currentPath_ = [];
// Canvas context properties
this.strokeStyle = "#000";
this.fillStyle = "#000";
this.lineWidth = 1;
this.lineJoin = "miter";
this.lineCap = "butt";
this.miterLimit = Z * 1;
this.globalAlpha = 1;
this.canvas = surfaceElement;
var el = surfaceElement.ownerDocument.createElement('div');
el.style.width = surfaceElement.clientWidth + 'px';
el.style.height = surfaceElement.clientHeight + 'px';
el.style.overflow = 'hidden';
el.style.position = 'absolute';
surfaceElement.appendChild(el);
this.element_ = el;
this.arcScaleX_ = 1;
this.arcScaleY_ = 1;
};
var contextPrototype = CanvasRenderingContext2D_.prototype;
contextPrototype.clearRect = function(){
this.element_.innerHTML = "";
this.currentPath_ = [];
};
contextPrototype.beginPath = function(){
// TODO: Branch current matrix so that save/restore has no effect
// as per safari docs.
this.currentPath_ = [];
};
contextPrototype.moveTo = function(aX, aY){
this.currentPath_.push({
type: "moveTo",
x: aX,
y: aY
});
this.currentX_ = aX;
this.currentY_ = aY;
};
contextPrototype.lineTo = function(aX, aY){
this.currentPath_.push({
type: "lineTo",
x: aX,
y: aY
});
this.currentX_ = aX;
this.currentY_ = aY;
};
contextPrototype.bezierCurveTo = function(aCP1x, aCP1y, aCP2x,
aCP2y, aX, aY){
this.currentPath_.push({
type: "bezierCurveTo",
cp1x: aCP1x,
cp1y: aCP1y,
cp2x: aCP2x,
cp2y: aCP2y,
x: aX,
y: aY
});
this.currentX_ = aX;
this.currentY_ = aY;
};
contextPrototype.quadraticCurveTo = function(aCPx, aCPy, aX, aY){
// the following is lifted almost directly from
//
http://developer.mozilla.org/en/docs/Canvas_tutorial:Drawing_shapes
var cp1x = this.currentX_ + 2.0 / 3.0 * (aCPx - this.currentX_);
var cp1y = this.currentY_ + 2.0 / 3.0 * (aCPy - this.currentY_);
var cp2x = cp1x + (aX - this.currentX_) / 3.0;
var cp2y = cp1y + (aY - this.currentY_) / 3.0;
this.bezierCurveTo(cp1x, cp1y, cp2x, cp2y, aX, aY);
};
contextPrototype.arc = function(aX, aY, aRadius, aStartAngle,
aEndAngle, aClockwise){
aRadius *= Z;
var arcType = aClockwise ? "at" : "wa";
var xStart = aX + (mc(aStartAngle) * aRadius) - Z2;
var yStart = aY + (ms(aStartAngle) * aRadius) - Z2;
var xEnd = aX + (mc(aEndAngle) * aRadius) - Z2;
var yEnd = aY + (ms(aEndAngle) * aRadius) - Z2;
// IE won't render arches drawn counter clockwise if xStart == xEnd.
if (xStart == xEnd && !aClockwise) {
xStart += 0.125; // Offset xStart by 1/80 of a pixel. Use
something
// that can be represented in binary
}
this.currentPath_.push({
type: arcType,
x: aX,
y: aY,
radius: aRadius,
xStart: xStart,
yStart: yStart,
xEnd: xEnd,
yEnd: yEnd
});
};
contextPrototype.rect = function(aX, aY, aWidth, aHeight){
this.moveTo(aX, aY);
this.lineTo(aX + aWidth, aY);
this.lineTo(aX + aWidth, aY + aHeight);
this.lineTo(aX, aY + aHeight);
this.closePath();
};
contextPrototype.strokeRect = function(aX, aY, aWidth, aHeight){
// Will destroy any existing path (same as FF behaviour)
this.beginPath();
this.moveTo(aX, aY);
this.lineTo(aX + aWidth, aY);
this.lineTo(aX + aWidth, aY + aHeight);
this.lineTo(aX, aY + aHeight);
this.closePath();
this.stroke();
};
contextPrototype.fillRect = function(aX, aY, aWidth, aHeight){
// Will destroy any existing path (same as FF behaviour)
this.beginPath();
this.moveTo(aX, aY);
this.lineTo(aX + aWidth, aY);
this.lineTo(aX + aWidth, aY + aHeight);
this.lineTo(aX, aY + aHeight);
this.closePath();
this.fill();
};
contextPrototype.createLinearGradient = function(aX0, aY0, aX1, aY1){
var gradient = new CanvasGradient_("gradient");
return gradient;
};
contextPrototype.createRadialGradient = function(aX0, aY0, aR0, aX1,
aY1, aR1){
var gradient = new CanvasGradient_("gradientradial");
gradient.radius1_ = aR0;
gradient.radius2_ = aR1;
gradient.focus_.x = aX0;
gradient.focus_.y = aY0;
return gradient;
};
contextPrototype.drawImage = function(image, var_args){
var dx, dy, dw, dh, sx, sy, sw, sh;
// to find the original width we overide the width and height
var oldRuntimeWidth = image.runtimeStyle.width;
var oldRuntimeHeight = image.runtimeStyle.height;
image.runtimeStyle.width = 'auto';
image.runtimeStyle.height = 'auto';
// get the original size
var w = image.width;
var h = image.height;
// and remove overides
image.runtimeStyle.width = oldRuntimeWidth;
image.runtimeStyle.height = oldRuntimeHeight;
if (arguments.length == 3) {
dx = arguments[1];
dy = arguments[2];
sx = sy = 0;
sw = dw = w;
sh = dh = h;
}
else
if (arguments.length == 5) {
dx = arguments[1];
dy = arguments[2];
dw = arguments[3];
dh = arguments[4];
sx = sy = 0;
sw = w;
sh = h;
}
else
if (arguments.length == 9) {
sx = arguments[1];
sy = arguments[2];
sw = arguments[3];
sh = arguments[4];
dx = arguments[5];
dy = arguments[6];
dw = arguments[7];
dh = arguments[8];
}
else {
throw "Invalid number of arguments";
}
var d = this.getCoords_(dx, dy);
var w2 = sw / 2;
var h2 = sh / 2;
var vmlStr = [];
var W = 10;
var H = 10;
// For some reason that I've now forgotten, using divs didn't work
vmlStr.push(' <g_vml_:group', ' coordsize="', Z * W, ',', Z * H,
'"', ' coordorigin="0,0"', ' style="width:', W, ';height:', H,
';position:absolute;');
// If filters are necessary (rotation exists), create them
// filters are bog-slow, so only create them if abbsolutely
necessary
// The following check doesn't account for skews (which don't exist
// in the canvas spec (yet) anyway.
if (this.m_[0][0] != 1 || this.m_[0][1]) {
var filter = [];
// Note the 12/21 reversal
filter.push("M11='", this.m_[0][0], "',", "M12='",
this.m_[1][0], "',", "M21='", this.m_[0][1], "',", "M22='",
this.m_[1][1], "',", "Dx='", mr(d.x / Z), "',", "Dy='", mr(d.y / Z), "'");
// Bounding box calculation (need to minimize displayed area
so that
// filters don't waste time on unused pixels.
var max = d;
var c2 = this.getCoords_(dx + dw, dy);
var c3 = this.getCoords_(dx, dy + dh);
var c4 = this.getCoords_(dx + dw, dy + dh);
max.x = Math.max(max.x, c2.x, c3.x, c4.x);
max.y = Math.max(max.y, c2.y, c3.y, c4.y);
vmlStr.push("padding:0 ", mr(max.x / Z), "px ", mr(max.y /
Z), "px 0;filter:progid:DXImageTransform.Microsoft.Matrix(",
filter.join(""), ", sizingmethod='clip');")
}
else {
vmlStr.push("top:", mr(d.y / Z), "px;left:", mr(d.x / Z), "px;")
}
vmlStr.push(' ">', '<g_vml_:image src="', image.src, '"', '
style="width:', Z * dw, ';', ' height:', Z * dh, ';"', ' cropleft="', sx
/ w, '"', ' croptop="', sy / h, '"', ' cropright="', (w - sx - sw) / w,
'"', ' cropbottom="', (h - sy - sh) / h, '"', ' />', '</g_vml_:group>');
this.element_.insertAdjacentHTML("BeforeEnd", vmlStr.join(""));
};
contextPrototype.stroke = function(aFill){
var lineStr = [];
var lineOpen = false;
var a = processStyle(aFill ? this.fillStyle : this.strokeStyle);
var color = a[0];
var opacity = a[1] * this.globalAlpha;
var W = 10;
var H = 10;
lineStr.push('<g_vml_:shape', ' fillcolor="', color, '"', '
filled="', Boolean(aFill), '"', ' style="position:absolute;width:', W,
';height:', H, ';"', ' coordorigin="0 0" coordsize="', Z * W, ' ', Z *
H, '"', ' stroked="', !aFill, '"', ' strokeweight="', this.lineWidth,
'"', ' strokecolor="', color, '"', ' path="');
var newSeq = false;
var min = {
x: null,
y: null
};
var max = {
x: null,
y: null
};
for (var i = 0; i < this.currentPath_.length; i++) {
var p = this.currentPath_[i];
if (p.type == "moveTo") {
lineStr.push(" m ");
var c = this.getCoords_(p.x, p.y);
lineStr.push(mr(c.x), ",", mr(c.y));
}
else
if (p.type == "lineTo") {
lineStr.push(" l ");
var c = this.getCoords_(p.x, p.y);
lineStr.push(mr(c.x), ",", mr(c.y));
}
else
if (p.type == "close") {
lineStr.push(" x ");
}
else
if (p.type == "bezierCurveTo") {
lineStr.push(" c ");
var c = this.getCoords_(p.x, p.y);
var c1 = this.getCoords_(p.cp1x, p.cp1y);
var c2 = this.getCoords_(p.cp2x, p.cp2y);
lineStr.push(mr(c1.x), ",", mr(c1.y), ",",
mr(c2.x), ",", mr(c2.y), ",", mr(c.x), ",", mr(c.y));
}
else
if (p.type == "at" || p.type == "wa") {
lineStr.push(" ", p.type, " ");
var c = this.getCoords_(p.x, p.y);
var cStart = this.getCoords_(p.xStart,
p.yStart);
var cEnd = this.getCoords_(p.xEnd, p.yEnd);
lineStr.push(mr(c.x - this.arcScaleX_ *
p.radius), ",", mr(c.y - this.arcScaleY_ * p.radius), " ", mr(c.x +
this.arcScaleX_ * p.radius), ",", mr(c.y + this.arcScaleY_ * p.radius),
" ", mr(cStart.x), ",", mr(cStart.y), " ", mr(cEnd.x), ",", mr(cEnd.y));
}
// TODO: Following is broken for curves due to
// move to proper paths.
// Figure out dimensions so we can do gradient fills
// properly
if (c) {
if (min.x == null || c.x < min.x) {
min.x = c.x;
}
if (max.x == null || c.x > max.x) {
max.x = c.x;
}
if (min.y == null || c.y < min.y) {
min.y = c.y;
}
if (max.y == null || c.y > max.y) {
max.y = c.y;
}
}
}
lineStr.push(' ">');
if (typeof this.fillStyle == "object") {
var focus = {
x: "50%",
y: "50%"
};
var width = (max.x - min.x);
var height = (max.y - min.y);
var dimension = (width > height) ? width : height;
focus.x = mr((this.fillStyle.focus_.x / width) * 100 + 50) +
"%";
focus.y = mr((this.fillStyle.focus_.y / height) * 100 + 50)
+ "%";
var colors = [];
// inside radius (%)
if (this.fillStyle.type_ == "gradientradial") {
var inside = (this.fillStyle.radius1_ / dimension * 100);
// percentage that outside radius exceeds inside radius
var expansion = (this.fillStyle.radius2_ / dimension *
100) - inside;
}
else {
var inside = 0;
var expansion = 100;
}
var insidecolor = {
offset: null,
color: null
};
var outsidecolor = {
offset: null,
color: null
};
// We need to sort 'colors' by percentage, from 0 > 100
otherwise ie
// won't interpret it correctly
this.fillStyle.colors_.sort(function(cs1, cs2){
return cs1.offset - cs2.offset;
});
for (var i = 0; i < this.fillStyle.colors_.length; i++) {
var fs = this.fillStyle.colors_[i];
colors.push((fs.offset * expansion) + inside, "% ",
fs.color, ",");
if (fs.offset > insidecolor.offset || insidecolor.offset
== null) {
insidecolor.offset = fs.offset;
insidecolor.color = fs.color;
}
if (fs.offset < outsidecolor.offset ||
outsidecolor.offset == null) {
outsidecolor.offset = fs.offset;
outsidecolor.color = fs.color;
}
}
colors.pop();
lineStr.push('<g_vml_:fill', ' color="', outsidecolor.color,
'"', ' color2="', insidecolor.color, '"', ' type="',
this.fillStyle.type_, '"', ' focusposition="', focus.x, ', ', focus.y,
'"', ' colors="', colors.join(""), '"', ' opacity="', opacity, '" />');
}
else
if (aFill) {
lineStr.push('<g_vml_:fill color="', color, '"
opacity="', opacity, '" />');
}
else {
lineStr.push('<g_vml_:stroke', ' opacity="', opacity,
'"', ' joinstyle="', this.lineJoin, '"', ' miterlimit="',
this.miterLimit, '"', ' endcap="', processLineCap(this.lineCap), '"', '
weight="', this.lineWidth, 'px"', ' color="', color, '" />');
}
lineStr.push("</g_vml_:shape>");
this.element_.insertAdjacentHTML("beforeEnd", lineStr.join(""));
this.currentPath_ = [];
};
contextPrototype.fill = function(){
this.stroke(true);
}
contextPrototype.closePath = function(){
this.currentPath_.push({
type: "close"
});
};
/**
* @private
*/
contextPrototype.getCoords_ = function(aX, aY){
return {
x: Z * (aX * this.m_[0][0] + aY * this.m_[1][0] +
this.m_[2][0]) - Z2,
y: Z * (aX * this.m_[0][1] + aY * this.m_[1][1] +
this.m_[2][1]) - Z2
}
};
contextPrototype.save = function(){
var o = {};
copyState(this, o);
this.aStack_.push(o);
this.mStack_.push(this.m_);
this.m_ = matrixMultiply(createMatrixIdentity(), this.m_);
};
contextPrototype.restore = function(){
copyState(this.aStack_.pop(), this);
this.m_ = this.mStack_.pop();
};
contextPrototype.translate = function(aX, aY){
var m1 = [[1, 0, 0], [0, 1, 0], [aX, aY, 1]];
this.m_ = matrixMultiply(m1, this.m_);
};
contextPrototype.rotate = function(aRot){
var c = mc(aRot);
var s = ms(aRot);
var m1 = [[c, s, 0], [-s, c, 0], [0, 0, 1]];
this.m_ = matrixMultiply(m1, this.m_);
};
contextPrototype.scale = function(aX, aY){
this.arcScaleX_ *= aX;
this.arcScaleY_ *= aY;
var m1 = [[aX, 0, 0], [0, aY, 0], [0, 0, 1]];
this.m_ = matrixMultiply(m1, this.m_);
};
/******** STUBS ********/
contextPrototype.clip = function(){
// TODO: Implement
};
contextPrototype.arcTo = function(){
// TODO: Implement
};
contextPrototype.createPattern = function(){
return new CanvasPattern_;
};
// Gradient / Pattern Stubs
function CanvasGradient_(aType){
this.type_ = aType;
this.radius1_ = 0;
this.radius2_ = 0;
this.colors_ = [];
this.focus_ = {
x: 0,
y: 0
};
}
CanvasGradient_.prototype.addColorStop = function(aOffset, aColor){
aColor = processStyle(aColor);
this.colors_.push({
offset: 1 - aOffset,
color: aColor
});
};
function CanvasPattern_(){
}
// set up externs
G_vmlCanvasManager = G_vmlCanvasManager_;
CanvasRenderingContext2D = CanvasRenderingContext2D_;
CanvasGradient = CanvasGradient_;
CanvasPattern = CanvasPattern_;
};
googleExCanvas();
} // if
