js为页面的指定区域生成base64图片
需要一个封装好的html2canvas.js
/*
html2canvas 0.4.1 <http://html2canvas.hertzen.com>
Copyright (c) 2013 Niklas von Hertzen
Released under MIT License
*/
(function(window, document, undefined){
"use strict";
var _html2canvas = {},
previousElement,
computedCSS,
html2canvas;
_html2canvas.Util = {};
_html2canvas.Util.log = function(a) {
if (_html2canvas.logging && window.console && console.log) {
}
};
_html2canvas.Util.trimText = (function(isNative){
return function(input) {
return isNative ? isNative.apply(input) : ((input || '') + '').replace( /^\s+|\s+$/g , '' );
};
})(String.prototype.trim);
_html2canvas.Util.asFloat = function(v) {
return parseFloat(v);
};
(function() {
// TODO: support all possible length values
var TEXT_SHADOW_PROPERTY = /((rgba|rgb)\([^\)]+\)(\s-?\d+px){0,})/g;
var TEXT_SHADOW_VALUES = /(-?\d+px)|(#.+)|(rgb\(.+\))|(rgba\(.+\))/g;
_html2canvas.Util.parseTextShadows = function (value) {
if (!value || value === 'none') {
return [];
}
// find multiple shadow declarations
var shadows = value.match(TEXT_SHADOW_PROPERTY),
results = [];
for (var i = 0; shadows && (i < shadows.length); i++) {
var s = shadows[i].match(TEXT_SHADOW_VALUES);
results.push({
color: s[0],
offsetX: s[1] ? s[1].replace('px', '') : 0,
offsetY: s[2] ? s[2].replace('px', '') : 0,
blur: s[3] ? s[3].replace('px', '') : 0
});
}
return results;
};
})();
_html2canvas.Util.parseBackgroundImage = function (value) {
var whitespace = ' \r\n\t',
method, definition, prefix, prefix_i, block, results = [],
c, mode = 0, numParen = 0, quote, args;
var appendResult = function(){
if(method) {
if(definition.substr( 0, 1 ) === '"') {
definition = definition.substr( 1, definition.length - 2 );
}
if(definition) {
args.push(definition);
}
if(method.substr( 0, 1 ) === '-' &&
(prefix_i = method.indexOf( '-', 1 ) + 1) > 0) {
prefix = method.substr( 0, prefix_i);
method = method.substr( prefix_i );
}
results.push({
prefix: prefix,
method: method.toLowerCase(),
value: block,
args: args
});
}
args = []; //for some odd reason, setting .length = 0 didn't work in safari
method =
prefix =
definition =
block = '';
};
appendResult();
for(var i = 0, ii = value.length; i<ii; i++) {
c = value[i];
if(mode === 0 && whitespace.indexOf( c ) > -1){
continue;
}
switch(c) {
case '"':
if(!quote) {
quote = c;
}
else if(quote === c) {
quote = null;
}
break;
case '(':
if(quote) { break; }
else if(mode === 0) {
mode = 1;
block += c;
continue;
} else {
numParen++;
}
break;
case ')':
if(quote) { break; }
else if(mode === 1) {
if(numParen === 0) {
mode = 0;
block += c;
appendResult();
continue;
} else {
numParen--;
}
}
break;
case ',':
if(quote) { break; }
else if(mode === 0) {
appendResult();
continue;
}
else if (mode === 1) {
if(numParen === 0 && !method.match(/^url$/i)) {
args.push(definition);
definition = '';
block += c;
continue;
}
}
break;
}
block += c;
if(mode === 0) { method += c; }
else { definition += c; }
}
appendResult();
return results;
};
_html2canvas.Util.Bounds = function (element) {
var clientRect, bounds = {};
if (element.getBoundingClientRect){
clientRect = element.getBoundingClientRect();
// TODO add scroll position to bounds, so no scrolling of window necessary
bounds.top = clientRect.top;
bounds.bottom = clientRect.bottom || (clientRect.top + clientRect.height);
bounds.left = clientRect.left;
bounds.width = element.offsetWidth;
bounds.height = element.offsetHeight;
}
return bounds;
};
// TODO ideally, we'd want everything to go through this function instead of Util.Bounds,
// but would require further work to calculate the correct positions for elements with offsetParents
_html2canvas.Util.OffsetBounds = function (element) {
var parent = element.offsetParent ? _html2canvas.Util.OffsetBounds(element.offsetParent) : {top: 0, left: 0};
return {
top: element.offsetTop + parent.top,
bottom: element.offsetTop + element.offsetHeight + parent.top,
left: element.offsetLeft + parent.left,
width: element.offsetWidth,
height: element.offsetHeight
};
};
function toPX(element, attribute, value ) {
var rsLeft = element.runtimeStyle && element.runtimeStyle[attribute],
left,
style = element.style;
// Check if we are not dealing with pixels, (Opera has issues with this)
// Ported from jQuery css.js
// From the awesome hack by Dean Edwards
// http://erik.eae.net/archives/2007/07/27/18.54.15/#comment-102291
// If we're not dealing with a regular pixel number
// but a number that has a weird ending, we need to convert it to pixels
if ( !/^-?[0-9]+\.?[0-9]*(?:px)?$/i.test( value ) && /^-?\d/.test(value) ) {
// Remember the original values
left = style.left;
// Put in the new values to get a computed value out
if (rsLeft) {
element.runtimeStyle.left = element.currentStyle.left;
}
style.left = attribute === "fontSize" ? "1em" : (value || 0);
value = style.pixelLeft + "px";
// Revert the changed values
style.left = left;
if (rsLeft) {
element.runtimeStyle.left = rsLeft;
}
}
if (!/^(thin|medium|thick)$/i.test(value)) {
return Math.round(parseFloat(value)) + "px";
}
return value;
}
function asInt(val) {
return parseInt(val, 10);
}
function parseBackgroundSizePosition(value, element, attribute, index) {
value = (value || '').split(',');
value = value[index || 0] || value[0] || 'auto';
value = _html2canvas.Util.trimText(value).split(' ');
if(attribute === 'backgroundSize' && (!value[0] || value[0].match(/cover|contain|auto/))) {
//these values will be handled in the parent function
} else {
value[0] = (value[0].indexOf( "%" ) === -1) ? toPX(element, attribute + "X", value[0]) : value[0];
if(value[1] === undefined) {
if(attribute === 'backgroundSize') {
value[1] = 'auto';
return value;
} else {
// IE 9 doesn't return double digit always
value[1] = value[0];
}
}
value[1] = (value[1].indexOf("%") === -1) ? toPX(element, attribute + "Y", value[1]) : value[1];
}
return value;
}
_html2canvas.Util.getCSS = function (element, attribute, index) {
if (previousElement !== element) {
computedCSS = document.defaultView.getComputedStyle(element, null);
}
var value = computedCSS[attribute];
if (/^background(Size|Position)$/.test(attribute)) {
return parseBackgroundSizePosition(value, element, attribute, index);
} else if (/border(Top|Bottom)(Left|Right)Radius/.test(attribute)) {
var arr = value.split(" ");
if (arr.length <= 1) {
arr[1] = arr[0];
}
return arr.map(asInt);
}
return value;
};
_html2canvas.Util.resizeBounds = function( current_width, current_height, target_width, target_height, stretch_mode ){
var target_ratio = target_width / target_height,
current_ratio = current_width / current_height,
output_width, output_height;
if(!stretch_mode || stretch_mode === 'auto') {
output_width = target_width;
output_height = target_height;
} else if(target_ratio < current_ratio ^ stretch_mode === 'contain') {
output_height = target_height;
output_width = target_height * current_ratio;
} else {
output_width = target_width;
output_height = target_width / current_ratio;
}
return {
width: output_width,
height: output_height
};
};
function backgroundBoundsFactory( prop, el, bounds, image, imageIndex, backgroundSize ) {
var bgposition = _html2canvas.Util.getCSS( el, prop, imageIndex ) ,
topPos,
left,
percentage,
val;
if (bgposition.length === 1){
val = bgposition[0];
bgposition = [];
bgposition[0] = val;
bgposition[1] = val;
}
if (bgposition[0].toString().indexOf("%") !== -1){
percentage = (parseFloat(bgposition[0])/100);
left = bounds.width * percentage;
if(prop !== 'backgroundSize') {
left -= (backgroundSize || image).width*percentage;
}
} else {
if(prop === 'backgroundSize') {
if(bgposition[0] === 'auto') {
left = image.width;
} else {
if (/contain|cover/.test(bgposition[0])) {
var resized = _html2canvas.Util.resizeBounds(image.width, image.height, bounds.width, bounds.height, bgposition[0]);
left = resized.width;
topPos = resized.height;
} else {
left = parseInt(bgposition[0], 10);
}
}
} else {
left = parseInt( bgposition[0], 10);
}
}
if(bgposition[1] === 'auto') {
topPos = left / image.width * image.height;
} else if (bgposition[1].toString().indexOf("%") !== -1){
percentage = (parseFloat(bgposition[1])/100);
topPos = bounds.height * percentage;
if(prop !== 'backgroundSize') {
topPos -= (backgroundSize || image).height * percentage;
}
} else {
topPos = parseInt(bgposition[1],10);
}
return [left, topPos];
}
_html2canvas.Util.BackgroundPosition = function( el, bounds, image, imageIndex, backgroundSize ) {
var result = backgroundBoundsFactory( 'backgroundPosition', el, bounds, image, imageIndex, backgroundSize );
return { left: result[0], top: result[1] };
};
_html2canvas.Util.BackgroundSize = function( el, bounds, image, imageIndex ) {
var result = backgroundBoundsFactory( 'backgroundSize', el, bounds, image, imageIndex );
return { width: result[0], height: result[1] };
};
_html2canvas.Util.Extend = function (options, defaults) {
for (var key in options) {
if (options.hasOwnProperty(key)) {
defaults[key] = options[key];
}
}
return defaults;
};
/*
* Derived from jQuery.contents()
* Copyright 2010, John Resig
* Dual licensed under the MIT or GPL Version 2 licenses.
* http://jquery.org/license
*/
_html2canvas.Util.Children = function( elem ) {
var children;
try {
children = (elem.nodeName && elem.nodeName.toUpperCase() === "IFRAME") ? elem.contentDocument || elem.contentWindow.document : (function(array) {
var ret = [];
if (array !== null) {
(function(first, second ) {
var i = first.length,
j = 0;
if (typeof second.length === "number") {
for (var l = second.length; j < l; j++) {
first[i++] = second[j];
}
} else {
while (second[j] !== undefined) {
first[i++] = second[j++];
}
}
first.length = i;
return first;
})(ret, array);
}
return ret;
})(elem.childNodes);
} catch (ex) {
_html2canvas.Util.log("html2canvas.Util.Children failed with exception: " + ex.message);
children = [];
}
return children;
};
_html2canvas.Util.isTransparent = function(backgroundColor) {
return (backgroundColor === "transparent" || backgroundColor === "rgba(0, 0, 0, 0)");
};
_html2canvas.Util.Font = (function () {
var fontData = {};
return function(font, fontSize, doc) {
if (fontData[font + "-" + fontSize] !== undefined) {
return fontData[font + "-" + fontSize];
}
var container = doc.createElement('div'),
img = doc.createElement('img'),
span = doc.createElement('span'),
sampleText = 'Hidden Text',
baseline,
middle,
metricsObj;
container.style.visibility = "hidden";
container.style.fontFamily = font;
container.style.fontSize = fontSize;
container.style.margin = 0;
container.style.padding = 0;
doc.body.appendChild(container);
// http://probablyprogramming.com/2009/03/15/the-tiniest-gif-ever (handtinywhite.gif)
img.src = "data:image/gif;base64,R0lGODlhAQABAIABAP///wAAACwAAAAAAQABAAACAkQBADs=";
img.width = 1;
img.height = 1;
img.style.margin = 0;
img.style.padding = 0;
img.style.verticalAlign = "baseline";
span.style.fontFamily = font;
span.style.fontSize = fontSize;
span.style.margin = 0;
span.style.padding = 0;
span.appendChild(doc.createTextNode(sampleText));
container.appendChild(span);
container.appendChild(img);
baseline = (img.offsetTop - span.offsetTop) + 1;
container.removeChild(span);
container.appendChild(doc.createTextNode(sampleText));
container.style.lineHeight = "normal";
img.style.verticalAlign = "super";
middle = (img.offsetTop-container.offsetTop) + 1;
metricsObj = {
baseline: baseline,
lineWidth: 1,
middle: middle
};
fontData[font + "-" + fontSize] = metricsObj;
doc.body.removeChild(container);
return metricsObj;
};
})();
(function(){
var Util = _html2canvas.Util,
Generate = {};
_html2canvas.Generate = Generate;
var reGradients = [
/^(-webkit-linear-gradient)\(([a-z\s]+)([\w\d\.\s,%\(\)]+)\)$/,
/^(-o-linear-gradient)\(([a-z\s]+)([\w\d\.\s,%\(\)]+)\)$/,
/^(-webkit-gradient)\((linear|radial),\s((?:\d{1,3}%?)\s(?:\d{1,3}%?),\s(?:\d{1,3}%?)\s(?:\d{1,3}%?))([\w\d\.\s,%\(\)\-]+)\)$/,
/^(-moz-linear-gradient)\(((?:\d{1,3}%?)\s(?:\d{1,3}%?))([\w\d\.\s,%\(\)]+)\)$/,
/^(-webkit-radial-gradient)\(((?:\d{1,3}%?)\s(?:\d{1,3}%?)),\s(\w+)\s([a-z\-]+)([\w\d\.\s,%\(\)]+)\)$/,
/^(-moz-radial-gradient)\(((?:\d{1,3}%?)\s(?:\d{1,3}%?)),\s(\w+)\s?([a-z\-]*)([\w\d\.\s,%\(\)]+)\)$/,
/^(-o-radial-gradient)\(((?:\d{1,3}%?)\s(?:\d{1,3}%?)),\s(\w+)\s([a-z\-]+)([\w\d\.\s,%\(\)]+)\)$/
];
/*
* TODO: Add IE10 vendor prefix (-ms) support
* TODO: Add W3C gradient (linear-gradient) support
* TODO: Add old Webkit -webkit-gradient(radial, ...) support
* TODO: Maybe some RegExp optimizations are possible ;o)
*/
Generate.parseGradient = function(css, bounds) {
var gradient, i, len = reGradients.length, m1, stop, m2, m2Len, step, m3, tl,tr,br,bl;
for(i = 0; i < len; i+=1){
m1 = css.match(reGradients[i]);
if(m1) {
break;
}
}
if(m1) {
switch(m1[1]) {
case '-webkit-linear-gradient':
case '-o-linear-gradient':
gradient = {
type: 'linear',
x0: null,
y0: null,
x1: null,
y1: null,
colorStops: []
};
// get coordinates
m2 = m1[2].match(/\w+/g);
if(m2){
m2Len = m2.length;
for(i = 0; i < m2Len; i+=1){
switch(m2[i]) {
case 'top':
gradient.y0 = 0;
gradient.y1 = bounds.height;
break;
case 'right':
gradient.x0 = bounds.width;
gradient.x1 = 0;
break;
case 'bottom':
gradient.y0 = bounds.height;
gradient.y1 = 0;
break;
case 'left':
gradient.x0 = 0;
gradient.x1 = bounds.width;
break;
}
}
}
if(gradient.x0 === null && gradient.x1 === null){ // center
gradient.x0 = gradient.x1 = bounds.width / 2;
}
if(gradient.y0 === null && gradient.y1 === null){ // center
gradient.y0 = gradient.y1 = bounds.height / 2;
}
// get colors and stops
m2 = m1[3].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\)(?:\s\d{1,3}(?:%|px))?)+/g);
if(m2){
m2Len = m2.length;
step = 1 / Math.max(m2Len - 1, 1);
for(i = 0; i < m2Len; i+=1){
m3 = m2[i].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\))\s*(\d{1,3})?(%|px)?/);
if(m3[2]){
stop = parseFloat(m3[2]);
if(m3[3] === '%'){
stop /= 100;
} else { // px - stupid opera
stop /= bounds.width;
}
} else {
stop = i * step;
}
gradient.colorStops.push({
color: m3[1],
stop: stop
});
}
}
break;
case '-webkit-gradient':
gradient = {
type: m1[2] === 'radial' ? 'circle' : m1[2], // TODO: Add radial gradient support for older mozilla definitions
x0: 0,
y0: 0,
x1: 0,
y1: 0,
colorStops: []
};
// get coordinates
m2 = m1[3].match(/(\d{1,3})%?\s(\d{1,3})%?,\s(\d{1,3})%?\s(\d{1,3})%?/);
if(m2){
gradient.x0 = (m2[1] * bounds.width) / 100;
gradient.y0 = (m2[2] * bounds.height) / 100;
gradient.x1 = (m2[3] * bounds.width) / 100;
gradient.y1 = (m2[4] * bounds.height) / 100;
}
// get colors and stops
m2 = m1[4].match(/((?:from|to|color-stop)\((?:[0-9\.]+,\s)?(?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\)\))+/g);
if(m2){
m2Len = m2.length;
for(i = 0; i < m2Len; i+=1){
m3 = m2[i].match(/(from|to|color-stop)\(([0-9\.]+)?(?:,\s)?((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\))\)/);
stop = parseFloat(m3[2]);
if(m3[1] === 'from') {
stop = 0.0;
}
if(m3[1] === 'to') {
stop = 1.0;
}
gradient.colorStops.push({
color: m3[3],
stop: stop
});
}
}
break;
case '-moz-linear-gradient':
gradient = {
type: 'linear',
x0: 0,
y0: 0,
x1: 0,
y1: 0,
colorStops: []
};
// get coordinates
m2 = m1[2].match(/(\d{1,3})%?\s(\d{1,3})%?/);
// m2[1] == 0% -> left
// m2[1] == 50% -> center
// m2[1] == 100% -> right
// m2[2] == 0% -> top
// m2[2] == 50% -> center
// m2[2] == 100% -> bottom
if(m2){
gradient.x0 = (m2[1] * bounds.width) / 100;
gradient.y0 = (m2[2] * bounds.height) / 100;
gradient.x1 = bounds.width - gradient.x0;
gradient.y1 = bounds.height - gradient.y0;
}
// get colors and stops
m2 = m1[3].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\)(?:\s\d{1,3}%)?)+/g);
if(m2){
m2Len = m2.length;
step = 1 / Math.max(m2Len - 1, 1);
for(i = 0; i < m2Len; i+=1){
m3 = m2[i].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\))\s*(\d{1,3})?(%)?/);
if(m3[2]){
stop = parseFloat(m3[2]);
if(m3[3]){ // percentage
stop /= 100;
}
} else {
stop = i * step;
}
gradient.colorStops.push({
color: m3[1],
stop: stop
});
}
}
break;
case '-webkit-radial-gradient':
case '-moz-radial-gradient':
case '-o-radial-gradient':
gradient = {
type: 'circle',
x0: 0,
y0: 0,
x1: bounds.width,
y1: bounds.height,
cx: 0,
cy: 0,
rx: 0,
ry: 0,
colorStops: []
};
// center
m2 = m1[2].match(/(\d{1,3})%?\s(\d{1,3})%?/);
if(m2){
gradient.cx = (m2[1] * bounds.width) / 100;
gradient.cy = (m2[2] * bounds.height) / 100;
}
// size
m2 = m1[3].match(/\w+/);
m3 = m1[4].match(/[a-z\-]*/);
if(m2 && m3){
switch(m3[0]){
case 'farthest-corner':
case 'cover': // is equivalent to farthest-corner
case '': // mozilla removes "cover" from definition :(
tl = Math.sqrt(Math.pow(gradient.cx, 2) + Math.pow(gradient.cy, 2));
tr = Math.sqrt(Math.pow(gradient.cx, 2) + Math.pow(gradient.y1 - gradient.cy, 2));
br = Math.sqrt(Math.pow(gradient.x1 - gradient.cx, 2) + Math.pow(gradient.y1 - gradient.cy, 2));
bl = Math.sqrt(Math.pow(gradient.x1 - gradient.cx, 2) + Math.pow(gradient.cy, 2));
gradient.rx = gradient.ry = Math.max(tl, tr, br, bl);
break;
case 'closest-corner':
tl = Math.sqrt(Math.pow(gradient.cx, 2) + Math.pow(gradient.cy, 2));
tr = Math.sqrt(Math.pow(gradient.cx, 2) + Math.pow(gradient.y1 - gradient.cy, 2));
br = Math.sqrt(Math.pow(gradient.x1 - gradient.cx, 2) + Math.pow(gradient.y1 - gradient.cy, 2));
bl = Math.sqrt(Math.pow(gradient.x1 - gradient.cx, 2) + Math.pow(gradient.cy, 2));
gradient.rx = gradient.ry = Math.min(tl, tr, br, bl);
break;
case 'farthest-side':
if(m2[0] === 'circle'){
gradient.rx = gradient.ry = Math.max(
gradient.cx,
gradient.cy,
gradient.x1 - gradient.cx,
gradient.y1 - gradient.cy
);
} else { // ellipse
gradient.type = m2[0];
gradient.rx = Math.max(
gradient.cx,
gradient.x1 - gradient.cx
);
gradient.ry = Math.max(
gradient.cy,
gradient.y1 - gradient.cy
);
}
break;
case 'closest-side':
case 'contain': // is equivalent to closest-side
if(m2[0] === 'circle'){
gradient.rx = gradient.ry = Math.min(
gradient.cx,
gradient.cy,
gradient.x1 - gradient.cx,
gradient.y1 - gradient.cy
);
} else { // ellipse
gradient.type = m2[0];
gradient.rx = Math.min(
gradient.cx,
gradient.x1 - gradient.cx
);
gradient.ry = Math.min(
gradient.cy,
gradient.y1 - gradient.cy
);
}
break;
// TODO: add support for "30px 40px" sizes (webkit only)
}
}
// color stops
m2 = m1[5].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\)(?:\s\d{1,3}(?:%|px))?)+/g);
if(m2){
m2Len = m2.length;
step = 1 / Math.max(m2Len - 1, 1);
for(i = 0; i < m2Len; i+=1){
m3 = m2[i].match(/((?:rgb|rgba)\(\d{1,3},\s\d{1,3},\s\d{1,3}(?:,\s[0-9\.]+)?\))\s*(\d{1,3})?(%|px)?/);
if(m3[2]){
stop = parseFloat(m3[2]);
if(m3[3] === '%'){
stop /= 100;
} else { // px - stupid opera
stop /= bounds.width;
}
} else {
stop = i * step;
}
gradient.colorStops.push({
color: m3[1],
stop: stop
});
}
}
break;
}
}
return gradient;
};
function addScrollStops(grad) {
return function(colorStop) {
try {
grad.addColorStop(colorStop.stop, colorStop.color);
}
catch(e) {
Util.log(['failed to add color stop: ', e, '; tried to add: ', colorStop]);
}
};
}
Generate.Gradient = function(src, bounds) {
if(bounds.width === 0 || bounds.height === 0) {
return;
}
var canvas = document.createElement('canvas'),
ctx = canvas.getContext('2d'),
gradient, grad;
canvas.width = bounds.width;
canvas.height = bounds.height;
// TODO: add support for multi defined background gradients
gradient = _html2canvas.Generate.parseGradient(src, bounds);
if(gradient) {
switch(gradient.type) {
case 'linear':
grad = ctx.createLinearGradient(gradient.x0, gradient.y0, gradient.x1, gradient.y1);
gradient.colorStops.forEach(addScrollStops(grad));
ctx.fillStyle = grad;
ctx.fillRect(0, 0, bounds.width, bounds.height);
break;
case 'circle':
grad = ctx.createRadialGradient(gradient.cx, gradient.cy, 0, gradient.cx, gradient.cy, gradient.rx);
gradient.colorStops.forEach(addScrollStops(grad));
ctx.fillStyle = grad;
ctx.fillRect(0, 0, bounds.width, bounds.height);
break;
case 'ellipse':
var canvasRadial = document.createElement('canvas'),
ctxRadial = canvasRadial.getContext('2d'),
ri = Math.max(gradient.rx, gradient.ry),
di = ri * 2;
canvasRadial.width = canvasRadial.height = di;
grad = ctxRadial.createRadialGradient(gradient.rx, gradient.ry, 0, gradient.rx, gradient.ry, ri);
gradient.colorStops.forEach(addScrollStops(grad));
ctxRadial.fillStyle = grad;
ctxRadial.fillRect(0, 0, di, di);
ctx.fillStyle = gradient.colorStops[gradient.colorStops.length - 1].color;
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.drawImage(canvasRadial, gradient.cx - gradient.rx, gradient.cy - gradient.ry, 2 * gradient.rx, 2 * gradient.ry);
break;
}
}
return canvas;
};
Generate.ListAlpha = function(number) {
var tmp = "",
modulus;
do {
modulus = number % 26;
tmp = String.fromCharCode((modulus) + 64) + tmp;
number = number / 26;
}while((number*26) > 26);
return tmp;
};
Generate.ListRoman = function(number) {
var romanArray = ["M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"],
decimal = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1],
roman = "",
v,
len = romanArray.length;
if (number <= 0 || number >= 4000) {
return number;
}
for (v=0; v < len; v+=1) {
while (number >= decimal[v]) {
number -= decimal[v];
roman += romanArray[v];
}
}
return roman;
};
})();
function h2cRenderContext(width, height) {
var storage = [];
return {
storage: storage,
width: width,
height: height,
clip: function() {
storage.push({
type: "function",
name: "clip",
'arguments': arguments
});
},
translate: function() {
storage.push({
type: "function",
name: "translate",
'arguments': arguments
});
},
fill: function() {
storage.push({
type: "function",
name: "fill",
'arguments': arguments
});
},
save: function() {
storage.push({
type: "function",
name: "save",
'arguments': arguments
});
},
restore: function() {
storage.push({
type: "function",
name: "restore",
'arguments': arguments
});
},
fillRect: function () {
storage.push({
type: "function",
name: "fillRect",
'arguments': arguments
});
},
createPattern: function() {
storage.push({
type: "function",
name: "createPattern",
'arguments': arguments
});
},
drawShape: function() {
var shape = [];
storage.push({
type: "function",
name: "drawShape",
'arguments': shape
});
return {
moveTo: function() {
shape.push({
name: "moveTo",
'arguments': arguments
});
},
lineTo: function() {
shape.push({
name: "lineTo",
'arguments': arguments
});
},
arcTo: function() {
shape.push({
name: "arcTo",
'arguments': arguments
});
},
bezierCurveTo: function() {
shape.push({
name: "bezierCurveTo",
'arguments': arguments
});
},
quadraticCurveTo: function() {
shape.push({
name: "quadraticCurveTo",
'arguments': arguments
});
}
};
},
drawImage: function () {
storage.push({
type: "function",
name: "drawImage",
'arguments': arguments
});
},
fillText: function () {
storage.push({
type: "function",
name: "fillText",
'arguments': arguments
});
},
setVariable: function (variable, value) {
storage.push({
type: "variable",
name: variable,
'arguments': value
});
return value;
}
};
}
_html2canvas.Parse = function (images, options) {
window.scroll(0,0);
var element = (( options.elements === undefined ) ? document.body : options.elements[0]), // select body by default
numDraws = 0,
doc = element.ownerDocument,
Util = _html2canvas.Util,
support = Util.Support(options, doc),
ignoreElementsRegExp = new RegExp("(" + options.ignoreElements + ")"),
body = doc.body,
getCSS = Util.getCSS,
pseudoHide = "___html2canvas___pseudoelement",
hidePseudoElements = doc.createElement('style');
hidePseudoElements.innerHTML = '.' + pseudoHide + '-before:before { content: "" !important; display: none !important; }' +
'.' + pseudoHide + '-after:after { content: "" !important; display: none !important; }';
body.appendChild(hidePseudoElements);
images = images || {};
function documentWidth () {
return Math.max(
Math.max(doc.body.scrollWidth, doc.documentElement.scrollWidth),
Math.max(doc.body.offsetWidth, doc.documentElement.offsetWidth),
Math.max(doc.body.clientWidth, doc.documentElement.clientWidth)
);
}
function documentHeight () {
return Math.max(
Math.max(doc.body.scrollHeight, doc.documentElement.scrollHeight),
Math.max(doc.body.offsetHeight, doc.documentElement.offsetHeight),
Math.max(doc.body.clientHeight, doc.documentElement.clientHeight)
);
}
function getCSSInt(element, attribute) {
var val = parseInt(getCSS(element, attribute), 10);
return (isNaN(val)) ? 0 : val; // borders in old IE are throwing 'medium' for demo.html
}
function renderRect (ctx, x, y, w, h, bgcolor) {
if (bgcolor !== "transparent"){
ctx.setVariable("fillStyle", bgcolor);
ctx.fillRect(x, y, w, h);
numDraws+=1;
}
}
function capitalize(m, p1, p2) {
if (m.length > 0) {
return p1 + p2.toUpperCase();
}
}
function textTransform (text, transform) {
switch(transform){
case "lowercase":
return text.toLowerCase();
case "capitalize":
return text.replace( /(^|\s|:|-|\(|\))([a-z])/g, capitalize);
case "uppercase":
return text.toUpperCase();
default:
return text;
}
}
function noLetterSpacing(letter_spacing) {
return (/^(normal|none|0px)$/.test(letter_spacing));
}
function drawText(currentText, x, y, ctx){
if (currentText !== null && Util.trimText(currentText).length > 0) {
ctx.fillText(currentText, x, y);
numDraws+=1;
}
}
function setTextVariables(ctx, el, text_decoration, color) {
var align = false,
bold = getCSS(el, "fontWeight"),
family = getCSS(el, "fontFamily"),
size = getCSS(el, "fontSize"),
shadows = Util.parseTextShadows(getCSS(el, "textShadow"));
switch(parseInt(bold, 10)){
case 401:
bold = "bold";
break;
case 400:
bold = "normal";
break;
}
ctx.setVariable("fillStyle", color);
ctx.setVariable("font", [getCSS(el, "fontStyle"), getCSS(el, "fontVariant"), bold, size, family].join(" "));
ctx.setVariable("textAlign", (align) ? "right" : "left");
if (shadows.length) {
// TODO: support multiple text shadows
// apply the first text shadow
ctx.setVariable("shadowColor", shadows[0].color);
ctx.setVariable("shadowOffsetX", shadows[0].offsetX);
ctx.setVariable("shadowOffsetY", shadows[0].offsetY);
ctx.setVariable("shadowBlur", shadows[0].blur);
}
if (text_decoration !== "none"){
return Util.Font(family, size, doc);
}
}
function renderTextDecoration(ctx, text_decoration, bounds, metrics, color) {
switch(text_decoration) {
case "underline":
// Draws a line at the baseline of the font
// TODO As some browsers display the line as more than 1px if the font-size is big, need to take that into account both in position and size
renderRect(ctx, bounds.left, Math.round(bounds.top + metrics.baseline + metrics.lineWidth), bounds.width, 1, color);
break;
case "overline":
renderRect(ctx, bounds.left, Math.round(bounds.top), bounds.width, 1, color);
break;
case "line-through":
// TODO try and find exact position for line-through
renderRect(ctx, bounds.left, Math.ceil(bounds.top + metrics.middle + metrics.lineWidth), bounds.width, 1, color);
break;
}
}
function getTextBounds(state, text, textDecoration, isLast, transform) {
var bounds;
if (support.rangeBounds && !transform) {
if (textDecoration !== "none" || Util.trimText(text).length !== 0) {
bounds = textRangeBounds(text, state.node, state.textOffset);
}
state.textOffset += text.length;
} else if (state.node && typeof state.node.nodeValue === "string" ){
var newTextNode = (isLast) ? state.node.splitText(text.length) : null;
bounds = textWrapperBounds(state.node, transform);
state.node = newTextNode;
}
return bounds;
}
function textRangeBounds(text, textNode, textOffset) {
var range = doc.createRange();
range.setStart(textNode, textOffset);
range.setEnd(textNode, textOffset + text.length);
return range.getBoundingClientRect();
}
function textWrapperBounds(oldTextNode, transform) {
var parent = oldTextNode.parentNode,
wrapElement = doc.createElement('wrapper'),
backupText = oldTextNode.cloneNode(true);
wrapElement.appendChild(oldTextNode.cloneNode(true));
parent.replaceChild(wrapElement, oldTextNode);
var bounds = transform ? Util.OffsetBounds(wrapElement) : Util.Bounds(wrapElement);
parent.replaceChild(backupText, wrapElement);
return bounds;
}
function renderText(el, textNode, stack) {
var ctx = stack.ctx,
color = getCSS(el, "color"),
textDecoration = getCSS(el, "textDecoration"),
textAlign = getCSS(el, "textAlign"),
metrics,
textList,
state = {
node: textNode,
textOffset: 0
};
if (Util.trimText(textNode.nodeValue).length > 0) {
textNode.nodeValue = textTransform(textNode.nodeValue, getCSS(el, "textTransform"));
textAlign = textAlign.replace(["-webkit-auto"],["auto"]);
textList = (!options.letterRendering && /^(left|right|justify|auto)$/.test(textAlign) && noLetterSpacing(getCSS(el, "letterSpacing"))) ?
textNode.nodeValue.split(/(\b| )/)
: textNode.nodeValue.split("");
metrics = setTextVariables(ctx, el, textDecoration, color);
if (options.chinese) {
textList.forEach(function(word, index) {
if (/.*[\u4E00-\u9FA5].*$/.test(word)) {
word = word.split("");
word.unshift(index, 1);
textList.splice.apply(textList, word);
}
});
}
textList.forEach(function(text, index) {
var bounds = getTextBounds(state, text, textDecoration, (index < textList.length - 1), stack.transform.matrix);
if (bounds) {
drawText(text, bounds.left, bounds.bottom, ctx);
renderTextDecoration(ctx, textDecoration, bounds, metrics, color);
}
});
}
}
function listPosition (element, val) {
var boundElement = doc.createElement( "boundelement" ),
originalType,
bounds;
boundElement.style.display = "inline";
originalType = element.style.listStyleType;
element.style.listStyleType = "none";
boundElement.appendChild(doc.createTextNode(val));
element.insertBefore(boundElement, element.firstChild);
bounds = Util.Bounds(boundElement);
element.removeChild(boundElement);
element.style.listStyleType = originalType;
return bounds;
}
function elementIndex(el) {
var i = -1,
count = 1,
childs = el.parentNode.childNodes;
if (el.parentNode) {
while(childs[++i] !== el) {
if (childs[i].nodeType === 1) {
count++;
}
}
return count;
} else {
return -1;
}
}
function listItemText(element, type) {
var currentIndex = elementIndex(element), text;
switch(type){
case "decimal":
text = currentIndex;
break;
case "decimal-leading-zero":
text = (currentIndex.toString().length === 1) ? currentIndex = "0" + currentIndex.toString() : currentIndex.toString();
break;
case "upper-roman":
text = _html2canvas.Generate.ListRoman( currentIndex );
break;
case "lower-roman":
text = _html2canvas.Generate.ListRoman( currentIndex ).toLowerCase();
break;
case "lower-alpha":
text = _html2canvas.Generate.ListAlpha( currentIndex ).toLowerCase();
break;
case "upper-alpha":
text = _html2canvas.Generate.ListAlpha( currentIndex );
break;
}
return text + ". ";
}
function renderListItem(element, stack, elBounds) {
var x,
text,
ctx = stack.ctx,
type = getCSS(element, "listStyleType"),
listBounds;
if (/^(decimal|decimal-leading-zero|upper-alpha|upper-latin|upper-roman|lower-alpha|lower-greek|lower-latin|lower-roman)$/i.test(type)) {
text = listItemText(element, type);
listBounds = listPosition(element, text);
setTextVariables(ctx, element, "none", getCSS(element, "color"));
if (getCSS(element, "listStylePosition") === "inside") {
ctx.setVariable("textAlign", "left");
x = elBounds.left;
} else {
return;
}
drawText(text, x, listBounds.bottom, ctx);
}
}
function loadImage (src){
var img = images[src];
return (img && img.succeeded === true) ? img.img : false;
}
function clipBounds(src, dst){
var x = Math.max(src.left, dst.left),
y = Math.max(src.top, dst.top),
x2 = Math.min((src.left + src.width), (dst.left + dst.width)),
y2 = Math.min((src.top + src.height), (dst.top + dst.height));
return {
left:x,
top:y,
width:x2-x,
height:y2-y
};
}
function setZ(element, stack, parentStack){
var newContext,
isPositioned = stack.cssPosition !== 'static',
zIndex = isPositioned ? getCSS(element, 'zIndex') : 'auto',
opacity = getCSS(element, 'opacity'),
isFloated = getCSS(element, 'cssFloat') !== 'none';
// https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Understanding_z_index/The_stacking_context
// When a new stacking context should be created:
// the root element (HTML),
// positioned (absolutely or relatively) with a z-index value other than "auto",
// elements with an opacity value less than 1. (See the specification for opacity),
// on mobile WebKit and Chrome 22+, position: fixed always creates a new stacking context, even when z-index is "auto" (See this post)
stack.zIndex = newContext = h2czContext(zIndex);
newContext.isPositioned = isPositioned;
newContext.isFloated = isFloated;
newContext.opacity = opacity;
newContext.ownStacking = (zIndex !== 'auto' || opacity < 1);
if (parentStack) {
parentStack.zIndex.children.push(stack);
}
}
function renderImage(ctx, element, image, bounds, borders) {
var paddingLeft = getCSSInt(element, 'paddingLeft'),
paddingTop = getCSSInt(element, 'paddingTop'),
paddingRight = getCSSInt(element, 'paddingRight'),
paddingBottom = getCSSInt(element, 'paddingBottom');
drawImage(
ctx,
image,
0, //sx
0, //sy
image.width, //sw
image.height, //sh
bounds.left + paddingLeft + borders[3].width, //dx
bounds.top + paddingTop + borders[0].width, // dy
bounds.width - (borders[1].width + borders[3].width + paddingLeft + paddingRight), //dw
bounds.height - (borders[0].width + borders[2].width + paddingTop + paddingBottom) //dh
);
}
function getBorderData(element) {
return ["Top", "Right", "Bottom", "Left"].map(function(side) {
return {
width: getCSSInt(element, 'border' + side + 'Width'),
color: getCSS(element, 'border' + side + 'Color')
};
});
}
function getBorderRadiusData(element) {
return ["TopLeft", "TopRight", "BottomRight", "BottomLeft"].map(function(side) {
return getCSS(element, 'border' + side + 'Radius');
});
}
var getCurvePoints = (function(kappa) {
return function(x, y, r1, r2) {
var ox = (r1) * kappa, // control point offset horizontal
oy = (r2) * kappa, // control point offset vertical
xm = x + r1, // x-middle
ym = y + r2; // y-middle
return {
topLeft: bezierCurve({
x:x,
y:ym
}, {
x:x,
y:ym - oy
}, {
x:xm - ox,
y:y
}, {
x:xm,
y:y
}),
topRight: bezierCurve({
x:x,
y:y
}, {
x:x + ox,
y:y
}, {
x:xm,
y:ym - oy
}, {
x:xm,
y:ym
}),
bottomRight: bezierCurve({
x:xm,
y:y
}, {
x:xm,
y:y + oy
}, {
x:x + ox,
y:ym
}, {
x:x,
y:ym
}),
bottomLeft: bezierCurve({
x:xm,
y:ym
}, {
x:xm - ox,
y:ym
}, {
x:x,
y:y + oy
}, {
x:x,
y:y
})
};
};
})(4 * ((Math.sqrt(2) - 1) / 3));
function bezierCurve(start, startControl, endControl, end) {
var lerp = function (a, b, t) {
return {
x:a.x + (b.x - a.x) * t,
y:a.y + (b.y - a.y) * t
};
};
return {
start: start,
startControl: startControl,
endControl: endControl,
end: end,
subdivide: function(t) {
var ab = lerp(start, startControl, t),
bc = lerp(startControl, endControl, t),
cd = lerp(endControl, end, t),
abbc = lerp(ab, bc, t),
bccd = lerp(bc, cd, t),
dest = lerp(abbc, bccd, t);
return [bezierCurve(start, ab, abbc, dest), bezierCurve(dest, bccd, cd, end)];
},
curveTo: function(borderArgs) {
borderArgs.push(["bezierCurve", startControl.x, startControl.y, endControl.x, endControl.y, end.x, end.y]);
},
curveToReversed: function(borderArgs) {
borderArgs.push(["bezierCurve", endControl.x, endControl.y, startControl.x, startControl.y, start.x, start.y]);
}
};
}
function parseCorner(borderArgs, radius1, radius2, corner1, corner2, x, y) {
if (radius1[0] > 0 || radius1[1] > 0) {
borderArgs.push(["line", corner1[0].start.x, corner1[0].start.y]);
corner1[0].curveTo(borderArgs);
corner1[1].curveTo(borderArgs);
} else {
borderArgs.push(["line", x, y]);
}
if (radius2[0] > 0 || radius2[1] > 0) {
borderArgs.push(["line", corner2[0].start.x, corner2[0].start.y]);
}
}
function drawSide(borderData, radius1, radius2, outer1, inner1, outer2, inner2) {
var borderArgs = [];
if (radius1[0] > 0 || radius1[1] > 0) {
borderArgs.push(["line", outer1[1].start.x, outer1[1].start.y]);
outer1[1].curveTo(borderArgs);
} else {
borderArgs.push([ "line", borderData.c1[0], borderData.c1[1]]);
}
if (radius2[0] > 0 || radius2[1] > 0) {
borderArgs.push(["line", outer2[0].start.x, outer2[0].start.y]);
outer2[0].curveTo(borderArgs);
borderArgs.push(["line", inner2[0].end.x, inner2[0].end.y]);
inner2[0].curveToReversed(borderArgs);
} else {
borderArgs.push([ "line", borderData.c2[0], borderData.c2[1]]);
borderArgs.push([ "line", borderData.c3[0], borderData.c3[1]]);
}
if (radius1[0] > 0 || radius1[1] > 0) {
borderArgs.push(["line", inner1[1].end.x, inner1[1].end.y]);
inner1[1].curveToReversed(borderArgs);
} else {
borderArgs.push([ "line", borderData.c4[0], borderData.c4[1]]);
}
return borderArgs;
}
function calculateCurvePoints(bounds, borderRadius, borders) {
var x = bounds.left,
y = bounds.top,
width = bounds.width,
height = bounds.height,
tlh = borderRadius[0][0],
tlv = borderRadius[0][1],
trh = borderRadius[1][0],
trv = borderRadius[1][1],
brh = borderRadius[2][0],
brv = borderRadius[2][1],
blh = borderRadius[3][0],
blv = borderRadius[3][1],
topWidth = width - trh,
rightHeight = height - brv,
bottomWidth = width - brh,
leftHeight = height - blv;
return {
topLeftOuter: getCurvePoints(
x,
y,
tlh,
tlv
).topLeft.subdivide(0.5),
topLeftInner: getCurvePoints(
x + borders[3].width,
y + borders[0].width,
Math.max(0, tlh - borders[3].width),
Math.max(0, tlv - borders[0].width)
).topLeft.subdivide(0.5),
topRightOuter: getCurvePoints(
x + topWidth,
y,
trh,
trv
).topRight.subdivide(0.5),
topRightInner: getCurvePoints(
x + Math.min(topWidth, width + borders[3].width),
y + borders[0].width,
(topWidth > width + borders[3].width) ? 0 :trh - borders[3].width,
trv - borders[0].width
).topRight.subdivide(0.5),
bottomRightOuter: getCurvePoints(
x + bottomWidth,
y + rightHeight,
brh,
brv
).bottomRight.subdivide(0.5),
bottomRightInner: getCurvePoints(
x + Math.min(bottomWidth, width + borders[3].width),
y + Math.min(rightHeight, height + borders[0].width),
Math.max(0, brh - borders[1].width),
Math.max(0, brv - borders[2].width)
).bottomRight.subdivide(0.5),
bottomLeftOuter: getCurvePoints(
x,
y + leftHeight,
blh,
blv
).bottomLeft.subdivide(0.5),
bottomLeftInner: getCurvePoints(
x + borders[3].width,
y + leftHeight,
Math.max(0, blh - borders[3].width),
Math.max(0, blv - borders[2].width)
).bottomLeft.subdivide(0.5)
};
}
function getBorderClip(element, borderPoints, borders, radius, bounds) {
var backgroundClip = getCSS(element, 'backgroundClip'),
borderArgs = [];
switch(backgroundClip) {
case "content-box":
case "padding-box":
parseCorner(borderArgs, radius[0], radius[1], borderPoints.topLeftInner, borderPoints.topRightInner, bounds.left + borders[3].width, bounds.top + borders[0].width);
parseCorner(borderArgs, radius[1], radius[2], borderPoints.topRightInner, borderPoints.bottomRightInner, bounds.left + bounds.width - borders[1].width, bounds.top + borders[0].width);
parseCorner(borderArgs, radius[2], radius[3], borderPoints.bottomRightInner, borderPoints.bottomLeftInner, bounds.left + bounds.width - borders[1].width, bounds.top + bounds.height - borders[2].width);
parseCorner(borderArgs, radius[3], radius[0], borderPoints.bottomLeftInner, borderPoints.topLeftInner, bounds.left + borders[3].width, bounds.top + bounds.height - borders[2].width);
break;
default:
parseCorner(borderArgs, radius[0], radius[1], borderPoints.topLeftOuter, borderPoints.topRightOuter, bounds.left, bounds.top);
parseCorner(borderArgs, radius[1], radius[2], borderPoints.topRightOuter, borderPoints.bottomRightOuter, bounds.left + bounds.width, bounds.top);
parseCorner(borderArgs, radius[2], radius[3], borderPoints.bottomRightOuter, borderPoints.bottomLeftOuter, bounds.left + bounds.width, bounds.top + bounds.height);
parseCorner(borderArgs, radius[3], radius[0], borderPoints.bottomLeftOuter, borderPoints.topLeftOuter, bounds.left, bounds.top + bounds.height);
break;
}
return borderArgs;
}
function parseBorders(element, bounds, borders){
var x = bounds.left,
y = bounds.top,
width = bounds.width,
height = bounds.height,
borderSide,
bx,
by,
bw,
bh,
borderArgs,
// http://www.w3.org/TR/css3-background/#the-border-radius
borderRadius = getBorderRadiusData(element),
borderPoints = calculateCurvePoints(bounds, borderRadius, borders),
borderData = {
clip: getBorderClip(element, borderPoints, borders, borderRadius, bounds),
borders: []
};
for (borderSide = 0; borderSide < 4; borderSide++) {
if (borders[borderSide].width > 0) {
bx = x;
by = y;
bw = width;
bh = height - (borders[2].width);
switch(borderSide) {
case 0:
// top border
bh = borders[0].width;
borderArgs = drawSide({
c1: [bx, by],
c2: [bx + bw, by],
c3: [bx + bw - borders[1].width, by + bh],
c4: [bx + borders[3].width, by + bh]
}, borderRadius[0], borderRadius[1],
borderPoints.topLeftOuter, borderPoints.topLeftInner, borderPoints.topRightOuter, borderPoints.topRightInner);
break;
case 1:
// right border
bx = x + width - (borders[1].width);
bw = borders[1].width;
borderArgs = drawSide({
c1: [bx + bw, by],
c2: [bx + bw, by + bh + borders[2].width],
c3: [bx, by + bh],
c4: [bx, by + borders[0].width]
}, borderRadius[1], borderRadius[2],
borderPoints.topRightOuter, borderPoints.topRightInner, borderPoints.bottomRightOuter, borderPoints.bottomRightInner);
break;
case 2:
// bottom border
by = (by + height) - (borders[2].width);
bh = borders[2].width;
borderArgs = drawSide({
c1: [bx + bw, by + bh],
c2: [bx, by + bh],
c3: [bx + borders[3].width, by],
c4: [bx + bw - borders[3].width, by]
}, borderRadius[2], borderRadius[3],
borderPoints.bottomRightOuter, borderPoints.bottomRightInner, borderPoints.bottomLeftOuter, borderPoints.bottomLeftInner);
break;
case 3:
// left border
bw = borders[3].width;
borderArgs = drawSide({
c1: [bx, by + bh + borders[2].width],
c2: [bx, by],
c3: [bx + bw, by + borders[0].width],
c4: [bx + bw, by + bh]
}, borderRadius[3], borderRadius[0],
borderPoints.bottomLeftOuter, borderPoints.bottomLeftInner, borderPoints.topLeftOuter, borderPoints.topLeftInner);
break;
}
borderData.borders.push({
args: borderArgs,
color: borders[borderSide].color
});
}
}
return borderData;
}
function createShape(ctx, args) {
var shape = ctx.drawShape();
args.forEach(function(border, index) {
shape[(index === 0) ? "moveTo" : border[0] + "To" ].apply(null, border.slice(1));
});
return shape;
}
function renderBorders(ctx, borderArgs, color) {
if (color !== "transparent") {
ctx.setVariable( "fillStyle", color);
createShape(ctx, borderArgs);
ctx.fill();
numDraws+=1;
}
}
function renderFormValue (el, bounds, stack){
var valueWrap = doc.createElement('valuewrap'),
cssPropertyArray = ['lineHeight','textAlign','fontFamily','color','fontSize','paddingLeft','paddingTop','width','height','border','borderLeftWidth','borderTopWidth'],
textValue,
textNode;
cssPropertyArray.forEach(function(property) {
try {
valueWrap.style[property] = getCSS(el, property);
} catch(e) {
// Older IE has issues with "border"
Util.log("html2canvas: Parse: Exception caught in renderFormValue: " + e.message);
}
});
valueWrap.style.borderColor = "black";
valueWrap.style.borderStyle = "solid";
valueWrap.style.display = "block";
valueWrap.style.position = "absolute";
if (/^(submit|reset|button|text|password)$/.test(el.type) || el.nodeName === "SELECT"){
valueWrap.style.lineHeight = getCSS(el, "height");
}
valueWrap.style.top = bounds.top + "px";
valueWrap.style.left = bounds.left + "px";
textValue = (el.nodeName === "SELECT") ? (el.options[el.selectedIndex] || 0).text : el.value;
if(!textValue) {
textValue = el.placeholder;
}
textNode = doc.createTextNode(textValue);
valueWrap.appendChild(textNode);
body.appendChild(valueWrap);
renderText(el, textNode, stack);
body.removeChild(valueWrap);
}
function drawImage (ctx) {
ctx.drawImage.apply(ctx, Array.prototype.slice.call(arguments, 1));
numDraws+=1;
}
function getPseudoElement(el, which) {
var elStyle = window.getComputedStyle(el, which);
if(!elStyle || !elStyle.content || elStyle.content === "none" || elStyle.content === "-moz-alt-content" || elStyle.display === "none") {
return;
}
var content = elStyle.content + '',
first = content.substr( 0, 1 );
//strips quotes
if(first === content.substr( content.length - 1 ) && first.match(/'|"/)) {
content = content.substr( 1, content.length - 2 );
}
var isImage = content.substr( 0, 3 ) === 'url',
elps = document.createElement( isImage ? 'img' : 'span' );
elps.className = pseudoHide + "-before " + pseudoHide + "-after";
Object.keys(elStyle).filter(indexedProperty).forEach(function(prop) {
// Prevent assigning of read only CSS Rules, ex. length, parentRule
try {
elps.style[prop] = elStyle[prop];
} catch (e) {
Util.log(['Tried to assign readonly property ', prop, 'Error:', e]);
}
});
if(isImage) {
elps.src = Util.parseBackgroundImage(content)[0].args[0];
} else {
elps.innerHTML = content;
}
return elps;
}
function indexedProperty(property) {
return (isNaN(window.parseInt(property, 10)));
}
function injectPseudoElements(el, stack) {
var before = getPseudoElement(el, ':before'),
after = getPseudoElement(el, ':after');
if(!before && !after) {
return;
}
if(before) {
el.className += " " + pseudoHide + "-before";
el.parentNode.insertBefore(before, el);
parseElement(before, stack, true);
el.parentNode.removeChild(before);
el.className = el.className.replace(pseudoHide + "-before", "").trim();
}
if (after) {
el.className += " " + pseudoHide + "-after";
el.appendChild(after);
parseElement(after, stack, true);
el.removeChild(after);
el.className = el.className.replace(pseudoHide + "-after", "").trim();
}
}
function renderBackgroundRepeat(ctx, image, backgroundPosition, bounds) {
var offsetX = Math.round(bounds.left + backgroundPosition.left),
offsetY = Math.round(bounds.top + backgroundPosition.top);
ctx.createPattern(image);
ctx.translate(offsetX, offsetY);
ctx.fill();
ctx.translate(-offsetX, -offsetY);
}
function backgroundRepeatShape(ctx, image, backgroundPosition, bounds, left, top, width, height) {
var args = [];
args.push(["line", Math.round(left), Math.round(top)]);
args.push(["line", Math.round(left + width), Math.round(top)]);
args.push(["line", Math.round(left + width), Math.round(height + top)]);
args.push(["line", Math.round(left), Math.round(height + top)]);
createShape(ctx, args);
ctx.save();
ctx.clip();
renderBackgroundRepeat(ctx, image, backgroundPosition, bounds);
ctx.restore();
}
function renderBackgroundColor(ctx, backgroundBounds, bgcolor) {
renderRect(
ctx,
backgroundBounds.left,
backgroundBounds.top,
backgroundBounds.width,
backgroundBounds.height,
bgcolor
);
}
function renderBackgroundRepeating(el, bounds, ctx, image, imageIndex) {
var backgroundSize = Util.BackgroundSize(el, bounds, image, imageIndex),
backgroundPosition = Util.BackgroundPosition(el, bounds, image, imageIndex, backgroundSize),
backgroundRepeat = getCSS(el, "backgroundRepeat").split(",").map(Util.trimText);
image = resizeImage(image, backgroundSize);
backgroundRepeat = backgroundRepeat[imageIndex] || backgroundRepeat[0];
switch (backgroundRepeat) {
case "repeat-x":
backgroundRepeatShape(ctx, image, backgroundPosition, bounds,
bounds.left, bounds.top + backgroundPosition.top, 99999, image.height);
break;
case "repeat-y":
backgroundRepeatShape(ctx, image, backgroundPosition, bounds,
bounds.left + backgroundPosition.left, bounds.top, image.width, 99999);
break;
case "no-repeat":
backgroundRepeatShape(ctx, image, backgroundPosition, bounds,
bounds.left + backgroundPosition.left, bounds.top + backgroundPosition.top, image.width, image.height);
break;
default:
renderBackgroundRepeat(ctx, image, backgroundPosition, {
top: bounds.top,
left: bounds.left,
width: image.width,
height: image.height
});
break;
}
}
function renderBackgroundImage(element, bounds, ctx) {
var backgroundImage = getCSS(element, "backgroundImage"),
backgroundImages = Util.parseBackgroundImage(backgroundImage),
image,
imageIndex = backgroundImages.length;
while(imageIndex--) {
backgroundImage = backgroundImages[imageIndex];
if (!backgroundImage.args || backgroundImage.args.length === 0) {
continue;
}
var key = backgroundImage.method === 'url' ?
backgroundImage.args[0] :
backgroundImage.value;
image = loadImage(key);
// TODO add support for background-origin
if (image) {
renderBackgroundRepeating(element, bounds, ctx, image, imageIndex);
} else {
Util.log("html2canvas: Error loading background:", backgroundImage);
}
}
}
function resizeImage(image, bounds) {
if(image.width === bounds.width && image.height === bounds.height) {
return image;
}
var ctx, canvas = doc.createElement('canvas');
canvas.width = bounds.width;
canvas.height = bounds.height;
ctx = canvas.getContext("2d");
drawImage(ctx, image, 0, 0, image.width, image.height, 0, 0, bounds.width, bounds.height );
return canvas;
}
function setOpacity(ctx, element, parentStack) {
return ctx.setVariable("globalAlpha", getCSS(element, "opacity") * ((parentStack) ? parentStack.opacity : 1));
}
function removePx(str) {
return str.replace("px", "");
}
var transformRegExp = /(matrix)\((.+)\)/;
function getTransform(element, parentStack) {
var transform = getCSS(element, "transform") || getCSS(element, "-webkit-transform") || getCSS(element, "-moz-transform") || getCSS(element, "-ms-transform") || getCSS(element, "-o-transform");
var transformOrigin = getCSS(element, "transform-origin") || getCSS(element, "-webkit-transform-origin") || getCSS(element, "-moz-transform-origin") || getCSS(element, "-ms-transform-origin") || getCSS(element, "-o-transform-origin") || "0px 0px";
transformOrigin = transformOrigin.split(" ").map(removePx).map(Util.asFloat);
var matrix;
if (transform && transform !== "none") {
var match = transform.match(transformRegExp);
if (match) {
switch(match[1]) {
case "matrix":
matrix = match[2].split(",").map(Util.trimText).map(Util.asFloat);
break;
}
}
}
return {
origin: transformOrigin,
matrix: matrix
};
}
function createStack(element, parentStack, bounds, transform) {
var ctx = h2cRenderContext((!parentStack) ? documentWidth() : bounds.width , (!parentStack) ? documentHeight() : bounds.height),
stack = {
ctx: ctx,
opacity: setOpacity(ctx, element, parentStack),
cssPosition: getCSS(element, "position"),
borders: getBorderData(element),
transform: transform,
clip: (parentStack && parentStack.clip) ? Util.Extend( {}, parentStack.clip ) : null
};
setZ(element, stack, parentStack);
// TODO correct overflow for absolute content residing under a static position
if (options.useOverflow === true && /(hidden|scroll|auto)/.test(getCSS(element, "overflow")) === true && /(BODY)/i.test(element.nodeName) === false){
stack.clip = (stack.clip) ? clipBounds(stack.clip, bounds) : bounds;
}
return stack;
}
function getBackgroundBounds(borders, bounds, clip) {
var backgroundBounds = {
left: bounds.left + borders[3].width,
top: bounds.top + borders[0].width,
width: bounds.width - (borders[1].width + borders[3].width),
height: bounds.height - (borders[0].width + borders[2].width)
};
if (clip) {
backgroundBounds = clipBounds(backgroundBounds, clip);
}
return backgroundBounds;
}
function getBounds(element, transform) {
var bounds = (transform.matrix) ? Util.OffsetBounds(element) : Util.Bounds(element);
transform.origin[0] += bounds.left;
transform.origin[1] += bounds.top;
return bounds;
}
function renderElement(element, parentStack, pseudoElement, ignoreBackground) {
var transform = getTransform(element, parentStack),
bounds = getBounds(element, transform),
image,
stack = createStack(element, parentStack, bounds, transform),
borders = stack.borders,
ctx = stack.ctx,
backgroundBounds = getBackgroundBounds(borders, bounds, stack.clip),
borderData = parseBorders(element, bounds, borders),
backgroundColor = (ignoreElementsRegExp.test(element.nodeName)) ? "#efefef" : getCSS(element, "backgroundColor");
createShape(ctx, borderData.clip);
ctx.save();
ctx.clip();
if (backgroundBounds.height > 0 && backgroundBounds.width > 0 && !ignoreBackground) {
renderBackgroundColor(ctx, bounds, backgroundColor);
renderBackgroundImage(element, backgroundBounds, ctx);
} else if (ignoreBackground) {
stack.backgroundColor = backgroundColor;
}
ctx.restore();
borderData.borders.forEach(function(border) {
renderBorders(ctx, border.args, border.color);
});
if (!pseudoElement) {
injectPseudoElements(element, stack);
}
switch(element.nodeName){
case "IMG":
if ((image = loadImage(element.getAttribute('src')))) {
renderImage(ctx, element, image, bounds, borders);
} else {
Util.log("html2canvas: Error loading <img>:" + element.getAttribute('src'));
}
break;
case "INPUT":
// TODO add all relevant type's, i.e. HTML5 new stuff
// todo add support for placeholder attribute for browsers which support it
if (/^(text|url|email|submit|button|reset)$/.test(element.type) && (element.value || element.placeholder || "").length > 0){
renderFormValue(element, bounds, stack);
}
break;
case "TEXTAREA":
if ((element.value || element.placeholder || "").length > 0){
renderFormValue(element, bounds, stack);
}
break;
case "SELECT":
if ((element.options||element.placeholder || "").length > 0){
renderFormValue(element, bounds, stack);
}
break;
case "LI":
renderListItem(element, stack, backgroundBounds);
break;
case "CANVAS":
renderImage(ctx, element, element, bounds, borders);
break;
}
return stack;
}
function isElementVisible(element) {
return (getCSS(element, 'display') !== "none" && getCSS(element, 'visibility') !== "hidden" && !element.hasAttribute("data-html2canvas-ignore"));
}
function parseElement (element, stack, pseudoElement) {
if (isElementVisible(element)) {
stack = renderElement(element, stack, pseudoElement, false) || stack;
if (!ignoreElementsRegExp.test(element.nodeName)) {
parseChildren(element, stack, pseudoElement);
}
}
}
function parseChildren(element, stack, pseudoElement) {
Util.Children(element).forEach(function(node) {
if (node.nodeType === node.ELEMENT_NODE) {
parseElement(node, stack, pseudoElement);
} else if (node.nodeType === node.TEXT_NODE) {
renderText(element, node, stack);
}
});
}
function init() {
var background = getCSS(document.documentElement, "backgroundColor"),
transparentBackground = (Util.isTransparent(background) && element === document.body),
stack = renderElement(element, null, false, transparentBackground);
parseChildren(element, stack);
if (transparentBackground) {
background = stack.backgroundColor;
}
body.removeChild(hidePseudoElements);
return {
backgroundColor: background,
stack: stack
};
}
return init();
};
function h2czContext(zindex) {
return {
zindex: zindex,
children: []
};
}
_html2canvas.Preload = function( options ) {
var images = {
numLoaded: 0, // also failed are counted here
numFailed: 0,
numTotal: 0,
cleanupDone: false
},
pageOrigin,
Util = _html2canvas.Util,
methods,
i,
count = 0;
var element = options.elements[0] || document.body,
doc = element.ownerDocument;
if(element.getElementsByTagName == undefined)
return;
var domImages = element.getElementsByTagName('img'), // Fetch images of the present element only
imgLen = domImages.length,
link = doc.createElement("a"),
supportCORS = (function( img ){
return (img.crossOrigin !== undefined);
})(new Image()),
timeoutTimer;
link.href = window.location.href;
pageOrigin = link.protocol + link.host;
function isSameOrigin(url){
link.href = url;
link.href = link.href; // YES, BELIEVE IT OR NOT, that is required for IE9 - http://jsfiddle.net/niklasvh/2e48b/
var origin = link.protocol + link.host;
return (origin === pageOrigin);
}
function start(){
Util.log("html2canvas: start: images: " + images.numLoaded + " / " + images.numTotal + " (failed: " + images.numFailed + ")");
if (!images.firstRun && images.numLoaded >= images.numTotal){
Util.log("Finished loading images: # " + images.numTotal + " (failed: " + images.numFailed + ")");
if (typeof options.complete === "function"){
options.complete(images);
}
}
}
// TODO modify proxy to serve images with CORS enabled, where available
function proxyGetImage(url, img, imageObj){
var callback_name,
scriptUrl = options.proxy,
script;
link.href = url;
url = link.href; // work around for pages with base href="" set - WARNING: this may change the url
callback_name = 'html2canvas_' + (count++);
imageObj.callbackname = callback_name;
if (scriptUrl.indexOf("?") > -1) {
scriptUrl += "&";
} else {
scriptUrl += "?";
}
scriptUrl += 'url=' + encodeURIComponent(url) + '&callback=' + callback_name;
script = doc.createElement("script");
window[callback_name] = function(a){
if (a.substring(0,6) === "error:"){
imageObj.succeeded = false;
images.numLoaded++;
images.numFailed++;
start();
} else {
setImageLoadHandlers(img, imageObj);
img.src = a;
}
window[callback_name] = undefined; // to work with IE<9 // NOTE: that the undefined callback property-name still exists on the window object (for IE<9)
try {
delete window[callback_name]; // for all browser that support this
} catch(ex) {}
script.parentNode.removeChild(script);
script = null;
delete imageObj.script;
delete imageObj.callbackname;
};
script.setAttribute("type", "text/javascript");
script.setAttribute("src", scriptUrl);
imageObj.script = script;
window.document.body.appendChild(script);
}
function loadPseudoElement(element, type) {
var style = window.getComputedStyle(element, type),
content = style.content;
if (content.substr(0, 3) === 'url') {
methods.loadImage(_html2canvas.Util.parseBackgroundImage(content)[0].args[0]);
}
loadBackgroundImages(style.backgroundImage, element);
}
function loadPseudoElementImages(element) {
loadPseudoElement(element, ":before");
loadPseudoElement(element, ":after");
}
function loadGradientImage(backgroundImage, bounds) {
var img = _html2canvas.Generate.Gradient(backgroundImage, bounds);
if (img !== undefined){
images[backgroundImage] = {
img: img,
succeeded: true
};
images.numTotal++;
images.numLoaded++;
start();
}
}
function invalidBackgrounds(background_image) {
return (background_image && background_image.method && background_image.args && background_image.args.length > 0 );
}
function loadBackgroundImages(background_image, el) {
var bounds;
_html2canvas.Util.parseBackgroundImage(background_image).filter(invalidBackgrounds).forEach(function(background_image) {
if (background_image.method === 'url') {
methods.loadImage(background_image.args[0]);
} else if(background_image.method.match(/\-?gradient$/)) {
if(bounds === undefined) {
bounds = _html2canvas.Util.Bounds(el);
}
loadGradientImage(background_image.value, bounds);
}
});
}
function getImages (el) {
var elNodeType = false;
// Firefox fails with permission denied on pages with iframes
try {
Util.Children(el).forEach(getImages);
}
catch( e ) {}
try {
elNodeType = el.nodeType;
} catch (ex) {
elNodeType = false;
Util.log("html2canvas: failed to access some element's nodeType - Exception: " + ex.message);
}
if (elNodeType === 1 || elNodeType === undefined) {
loadPseudoElementImages(el);
try {
loadBackgroundImages(Util.getCSS(el, 'backgroundImage'), el);
} catch(e) {
Util.log("html2canvas: failed to get background-image - Exception: " + e.message);
}
loadBackgroundImages(el);
}
}
function setImageLoadHandlers(img, imageObj) {
img.onload = function() {
if ( imageObj.timer !== undefined ) {
// CORS succeeded
window.clearTimeout( imageObj.timer );
}
images.numLoaded++;
imageObj.succeeded = true;
img.onerror = img.onload = null;
start();
};
img.onerror = function() {
if (img.crossOrigin === "anonymous") {
// CORS failed
window.clearTimeout( imageObj.timer );
// let's try with proxy instead
if ( options.proxy ) {
var src = img.src;
img = new Image();
imageObj.img = img;
img.src = src;
proxyGetImage( img.src, img, imageObj );
return;
}
}
images.numLoaded++;
images.numFailed++;
imageObj.succeeded = false;
img.onerror = img.onload = null;
start();
};
}
methods = {
loadImage: function( src ) {
var img, imageObj;
if ( src && images[src] === undefined ) {
img = new Image();
if ( src.match(/data:image\/.*;base64,/i) ) {
img.src = src.replace(/url\(['"]{0,}|['"]{0,}\)$/ig, '');
imageObj = images[src] = {
img: img
};
images.numTotal++;
setImageLoadHandlers(img, imageObj);
} else if ( isSameOrigin( src ) || options.allowTaint === true ) {
imageObj = images[src] = {
img: img
};
images.numTotal++;
setImageLoadHandlers(img, imageObj);
img.src = src;
} else if ( supportCORS && !options.allowTaint && options.useCORS ) {
// attempt to load with CORS
img.crossOrigin = "anonymous";
imageObj = images[src] = {
img: img
};
images.numTotal++;
setImageLoadHandlers(img, imageObj);
img.src = src;
} else if ( options.proxy ) {
imageObj = images[src] = {
img: img
};
images.numTotal++;
proxyGetImage( src, img, imageObj );
}
}
},
cleanupDOM: function(cause) {
var img, src;
if (!images.cleanupDone) {
if (cause && typeof cause === "string") {
Util.log("html2canvas: Cleanup because: " + cause);
} else {
Util.log("html2canvas: Cleanup after timeout: " + options.timeout + " ms.");
}
for (src in images) {
if (images.hasOwnProperty(src)) {
img = images[src];
if (typeof img === "object" && img.callbackname && img.succeeded === undefined) {
// cancel proxy image request
window[img.callbackname] = undefined; // to work with IE<9 // NOTE: that the undefined callback property-name still exists on the window object (for IE<9)
try {
delete window[img.callbackname]; // for all browser that support this
} catch(ex) {}
if (img.script && img.script.parentNode) {
img.script.setAttribute("src", "about:blank"); // try to cancel running request
img.script.parentNode.removeChild(img.script);
}
images.numLoaded++;
images.numFailed++;
Util.log("html2canvas: Cleaned up failed img: '" + src + "' Steps: " + images.numLoaded + " / " + images.numTotal);
}
}
}
// cancel any pending requests
if(window.stop !== undefined) {
window.stop();
} else if(document.execCommand !== undefined) {
document.execCommand("Stop", false);
}
if (document.close !== undefined) {
document.close();
}
images.cleanupDone = true;
if (!(cause && typeof cause === "string")) {
start();
}
}
},
renderingDone: function() {
if (timeoutTimer) {
window.clearTimeout(timeoutTimer);
}
}
};
if (options.timeout > 0) {
timeoutTimer = window.setTimeout(methods.cleanupDOM, options.timeout);
}
Util.log('html2canvas: Preload starts: finding background-images');
images.firstRun = true;
getImages(element);
Util.log('html2canvas: Preload: Finding images');
// load <img> images
for (i = 0; i < imgLen; i+=1){
methods.loadImage( domImages[i].getAttribute( "src" ) );
}
images.firstRun = false;
Util.log('html2canvas: Preload: Done.');
if (images.numTotal === images.numLoaded) {
start();
}
return methods;
};
_html2canvas.Renderer = function(parseQueue, options){
// http://www.w3.org/TR/CSS21/zindex.html
function createRenderQueue(parseQueue) {
var queue = [],
rootContext;
rootContext = (function buildStackingContext(rootNode) {
var rootContext = {};
function insert(context, node, specialParent) {
var zi = (node.zIndex.zindex === 'auto') ? 0 : Number(node.zIndex.zindex),
contextForChildren = context, // the stacking context for children
isPositioned = node.zIndex.isPositioned,
isFloated = node.zIndex.isFloated,
stub = {node: node},
childrenDest = specialParent; // where children without z-index should be pushed into
if (node.zIndex.ownStacking) {
// '!' comes before numbers in sorted array
contextForChildren = stub.context = { '!': [{node:node, children: []}]};
childrenDest = undefined;
} else if (isPositioned || isFloated) {
childrenDest = stub.children = [];
}
if (zi === 0 && specialParent) {
specialParent.push(stub);
} else {
if (!context[zi]) { context[zi] = []; }
context[zi].push(stub);
}
node.zIndex.children.forEach(function(childNode) {
insert(contextForChildren, childNode, childrenDest);
});
}
insert(rootContext, rootNode);
return rootContext;
})(parseQueue);
function sortZ(context) {
Object.keys(context).sort().forEach(function(zi) {
var nonPositioned = [],
floated = [],
positioned = [],
list = [];
// positioned after static
context[zi].forEach(function(v) {
if (v.node.zIndex.isPositioned || v.node.zIndex.opacity < 1) {
// http://www.w3.org/TR/css3-color/#transparency
// non-positioned element with opactiy < 1 should be stacked as if it were a positioned element with ‘z-index: 0’ and ‘opacity: 1’.
positioned.push(v);
} else if (v.node.zIndex.isFloated) {
floated.push(v);
} else {
nonPositioned.push(v);
}
});
(function walk(arr) {
arr.forEach(function(v) {
list.push(v);
if (v.children) { walk(v.children); }
});
})(nonPositioned.concat(floated, positioned));
list.forEach(function(v) {
if (v.context) {
sortZ(v.context);
} else {
queue.push(v.node);
}
});
});
}
sortZ(rootContext);
return queue;
}
function getRenderer(rendererName) {
var renderer;
if (typeof options.renderer === "string" && _html2canvas.Renderer[rendererName] !== undefined) {
renderer = _html2canvas.Renderer[rendererName](options);
} else if (typeof rendererName === "function") {
renderer = rendererName(options);
} else {
throw new Error("Unknown renderer");
}
if ( typeof renderer !== "function" ) {
throw new Error("Invalid renderer defined");
}
return renderer;
}
return getRenderer(options.renderer)(parseQueue, options, document, createRenderQueue(parseQueue.stack), _html2canvas);
};
_html2canvas.Util.Support = function (options, doc) {
function supportSVGRendering() {
var img = new Image(),
canvas = doc.createElement("canvas"),
ctx = (canvas.getContext === undefined) ? false : canvas.getContext("2d");
if (ctx === false) {
return false;
}
canvas.width = canvas.height = 10;
img.src = [
"data:image/svg+xml,",
"<svg xmlns='http://www.w3.org/2000/svg' width='10' height='10'>",
"<foreignObject width='10' height='10'>",
"<div xmlns='http://www.w3.org/1999/xhtml' style='width:10;height:10;'>",
"sup",
"</div>",
"</foreignObject>",
"</svg>"
].join("");
try {
ctx.drawImage(img, 0, 0);
canvas.toDataURL();
} catch(e) {
return false;
}
_html2canvas.Util.log('html2canvas: Parse: SVG powered rendering available');
return true;
}
// Test whether we can use ranges to measure bounding boxes
// Opera doesn't provide valid bounds.height/bottom even though it supports the method.
function supportRangeBounds() {
var r, testElement, rangeBounds, rangeHeight, support = false;
if (doc.createRange) {
r = doc.createRange();
if (r.getBoundingClientRect) {
testElement = doc.createElement('boundtest');
testElement.style.height = "123px";
testElement.style.display = "block";
doc.body.appendChild(testElement);
r.selectNode(testElement);
rangeBounds = r.getBoundingClientRect();
rangeHeight = rangeBounds.height;
if (rangeHeight === 123) {
support = true;
}
doc.body.removeChild(testElement);
}
}
return support;
}
return {
rangeBounds: supportRangeBounds(),
svgRendering: options.svgRendering && supportSVGRendering()
};
};
window.html2canvas = function(elements, opts, userWidth, userHeight) {
elements = (elements.length) ? elements : [elements];
var queue,
canvas,
options = {
// general
logging: false,
elements: elements,
background: "#fff",
// preload options
proxy: null,
timeout: 0, // no timeout
useCORS: false, // try to load images as CORS (where available), before falling back to proxy
allowTaint: false, // whether to allow images to taint the canvas, won't need proxy if set to true
// parse options
svgRendering: false, // use svg powered rendering where available (FF11+)
ignoreElements: "IFRAME|OBJECT|PARAM",
useOverflow: true,
letterRendering: false,
chinese: false,
// render options
width: userWidth,
height: userHeight,
taintTest: true, // do a taint test with all images before applying to canvas
renderer: "Canvas"
};
options = _html2canvas.Util.Extend(opts, options);
_html2canvas.logging = options.logging;
options.complete = function( images ) {
if (typeof options.onpreloaded === "function") {
if ( options.onpreloaded( images ) === false ) {
return;
}
}
queue = _html2canvas.Parse( images, options );
if (typeof options.onparsed === "function") {
if ( options.onparsed( queue ) === false ) {
return;
}
}
canvas = _html2canvas.Renderer( queue, options );
if (typeof options.onrendered === "function") {
options.onrendered( canvas );
}
};
// for pages without images, we still want this to be async, i.e. return methods before executing
window.setTimeout( function(){
_html2canvas.Preload( options );
}, 0 );
return {
render: function( queue, opts ) {
return _html2canvas.Renderer( queue, _html2canvas.Util.Extend(opts, options) );
},
parse: function( images, opts ) {
return _html2canvas.Parse( images, _html2canvas.Util.Extend(opts, options) );
},
preload: function( opts ) {
return _html2canvas.Preload( _html2canvas.Util.Extend(opts, options) );
},
log: _html2canvas.Util.log
};
};
window.html2canvas.log = _html2canvas.Util.log; // for renderers
window.html2canvas.Renderer = {
Canvas: undefined // We are assuming this will be used
};
_html2canvas.Renderer.Canvas = function(options) {
options = options || {};
var doc = document,
safeImages = [],
testCanvas = document.createElement("canvas"),
testctx = testCanvas.getContext("2d"),
Util = _html2canvas.Util,
canvas = options.canvas || doc.createElement('canvas');
function createShape(ctx, args) {
ctx.beginPath();
args.forEach(function(arg) {
ctx[arg.name].apply(ctx, arg['arguments']);
});
ctx.closePath();
}
function safeImage(item) {
if (safeImages.indexOf(item['arguments'][0].src ) === -1) {
testctx.drawImage(item['arguments'][0], 0, 0);
try {
testctx.getImageData(0, 0, 1, 1);
} catch(e) {
testCanvas = doc.createElement("canvas");
testctx = testCanvas.getContext("2d");
return false;
}
safeImages.push(item['arguments'][0].src);
}
return true;
}
function renderItem(ctx, item) {
switch(item.type){
case "variable":
ctx[item.name] = item['arguments'];
break;
case "function":
switch(item.name) {
case "createPattern":
if (item['arguments'][0].width > 0 && item['arguments'][0].height > 0) {
try {
ctx.fillStyle = ctx.createPattern(item['arguments'][0], "repeat");
}
catch(e) {
Util.log("html2canvas: Renderer: Error creating pattern", e.message);
}
}
break;
case "drawShape":
createShape(ctx, item['arguments']);
break;
case "drawImage":
if (item['arguments'][8] > 0 && item['arguments'][7] > 0) {
if (!options.taintTest || (options.taintTest && safeImage(item))) {
ctx.drawImage.apply( ctx, item['arguments'] );
}
}
break;
default:
ctx[item.name].apply(ctx, item['arguments']);
}
break;
}
}
return function(parsedData, options, document, queue, _html2canvas) {
var ctx = canvas.getContext("2d"),
newCanvas,
bounds,
fstyle,
zStack = parsedData.stack;
canvas.width = canvas.style.width = options.width || zStack.ctx.width;
canvas.height = canvas.style.height = options.height || zStack.ctx.height;
fstyle = ctx.fillStyle;
ctx.fillStyle = (Util.isTransparent(zStack.backgroundColor) && options.background !== undefined) ? options.background : parsedData.backgroundColor;
ctx.fillRect(0, 0, canvas.width, canvas.height);
ctx.fillStyle = fstyle;
queue.forEach(function(storageContext) {
// set common settings for canvas
ctx.textBaseline = "bottom";
ctx.save();
if (storageContext.transform.matrix) {
ctx.translate(storageContext.transform.origin[0], storageContext.transform.origin[1]);
ctx.transform.apply(ctx, storageContext.transform.matrix);
ctx.translate(-storageContext.transform.origin[0], -storageContext.transform.origin[1]);
}
if (storageContext.clip){
ctx.beginPath();
ctx.rect(storageContext.clip.left, storageContext.clip.top, storageContext.clip.width, storageContext.clip.height);
ctx.clip();
}
if (storageContext.ctx.storage) {
storageContext.ctx.storage.forEach(function(item) {
renderItem(ctx, item);
});
}
ctx.restore();
});
Util.log("html2canvas: Renderer: Canvas renderer done - returning canvas obj");
if (options.elements.length === 1) {
if (typeof options.elements[0] === "object" && options.elements[0].nodeName !== "BODY") {
// crop image to the bounds of selected (single) element
bounds = _html2canvas.Util.Bounds(options.elements[0]);
newCanvas = document.createElement('canvas');
newCanvas.width = Math.ceil(bounds.width);
newCanvas.height = Math.ceil(bounds.height);
ctx = newCanvas.getContext("2d");
ctx.drawImage(canvas, bounds.left, bounds.top, bounds.width, bounds.height, 0, 0, bounds.width, bounds.height);
canvas = null;
return newCanvas;
}
}
return canvas;
};
};
})(window,document);
然后你需要编写你处理的区域的js
html2canvas($("#make"), { //指定区域
allowTaint: true,
taintTest: false,
onrendered: function(canvas) {
var dataUrl = canvas.toDataURL("image/png");
$("#make").html("<img src="+dataUrl+">");//将图片在什么位置展示
//dataUrl----base64图片
}});
