// Copyright 2006 Google Inc.//// 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) {(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_;})();} // if
