#

API Docs for: 3.10.3
Show: Inherited Protected Private Deprecated

# File: graphics/js/CanvasGraphic.js

    /**
     * <a href="http://www.w3.org/TR/html5/the-canvas-element.html">Canvas</a> implementation of the `Graphic` class.
     * `CanvasGraphic` is not intended to be used directly. Instead, use the <a href="Graphic.html">`Graphic`</a> class.
     * If the browser lacks <a href="http://www.w3.org/TR/SVG/">SVG</a> capabilities but has
     * <a href="http://www.w3.org/TR/html5/the-canvas-element.html">Canvas</a> capabilities, the <a href="Graphic.html">`Graphic`</a>
     * class will point to the `CanvasGraphic` class.
     *
     * @module graphics
     * @class CanvasGraphic
     * @constructor
     */
    function CanvasGraphic() {

        CanvasGraphic.superclass.constructor.apply(this, arguments);
    }

    CanvasGraphic.NAME = "canvasGraphic";

    CanvasGraphic.ATTRS = {
        /**
         * Whether or not to render the `Graphic` automatically after to a specified parent node after init. This can be a Node
         * instance or a CSS selector string.
         *
         * @config render
         * @type Node | String
         */
        render: {},

        /**
    	 * Unique id for class instance.
    	 *
    	 * @config id
    	 * @type String
    	 */
    	id: {
    		valueFn: function()
    		{
    			return Y.guid();
    		},

    		setter: function(val)
    		{
    			var node = this._node;
    			if(node)
    			{
    				node.setAttribute("id", val);
    			}
    			return val;
    		}
    	},

        /**
         * Key value pairs in which a shape instance is associated with its id.
         *
         *  @config shapes
         *  @type Object
         *  @readOnly
         */
        shapes: {
            readOnly: true,

            getter: function()
            {
                return this._shapes;
            }
        },

        /**
         *  Object containing size and coordinate data for the content of a Graphic in relation to the graphic instance's position.
         *
         *  @config contentBounds
         *  @type Object
         *  @readOnly
         */
        contentBounds: {
            readOnly: true,

            getter: function()
            {
                return this._contentBounds;
            }
        },

        /**
         *  The outermost html element of the Graphic instance.
         *
         *  @config node
         *  @type HTMLElement
         *  @readOnly
         */
        node: {
            readOnly: true,

            getter: function()
            {
                return this._node;
            }
        },

    	/**
    	 * Indicates the width of the `Graphic`.
    	 *
    	 * @config width
    	 * @type Number
    	 */
        width: {
            setter: function(val)
            {
                if(this._node)
                {
                    this._node.style.width = val + "px";
                }
                return val;
            }
        },

    	/**
    	 * Indicates the height of the `Graphic`.
    	 *
    	 * @config height
    	 * @type Number
    	 */
        height: {
            setter: function(val)
            {
                if(this._node)
                {
                    this._node.style.height = val + "px";
                }
                return val;
            }
        },

        /**
         *  Determines the sizing of the Graphic.
         *
         *  <dl>
         *      <dt>sizeContentToGraphic</dt><dd>The Graphic's width and height attributes are, either explicitly set through the
         *      <code>width</code> and <code>height</code> attributes or are determined by the dimensions of the parent element. The
         *      content contained in the Graphic will be sized to fit with in the Graphic instance's dimensions. When using this
         *      setting, the <code>preserveAspectRatio</code> attribute will determine how the contents are sized.</dd>
         *      <dt>sizeGraphicToContent</dt><dd>(Also accepts a value of true) The Graphic's width and height are determined by the
         *      size and positioning of the content.</dd>
         *      <dt>false</dt><dd>The Graphic's width and height attributes are, either explicitly set through the <code>width</code>
         *      and <code>height</code> attributes or are determined by the dimensions of the parent element. The contents of the
         *      Graphic instance are not affected by this setting.</dd>
         *  </dl>
         *
         *
         *  @config autoSize
         *  @type Boolean | String
         *  @default false
         */
        autoSize: {
            value: false
        },

        /**
         * Determines how content is sized when <code>autoSize</code> is set to <code>sizeContentToGraphic</code>.
         *
         *  <dl>
         *      <dt>none<dt><dd>Do not force uniform scaling. Scale the graphic content of the given element non-uniformly if necessary
         *      such that the element's bounding box exactly matches the viewport rectangle.</dd>
         *      <dt>xMinYMin</dt><dd>Force uniform scaling position along the top left of the Graphic's node.</dd>
         *      <dt>xMidYMin</dt><dd>Force uniform scaling horizontally centered and positioned at the top of the Graphic's node.<dd>
         *      <dt>xMaxYMin</dt><dd>Force uniform scaling positioned horizontally from the right and vertically from the top.</dd>
         *      <dt>xMinYMid</dt>Force uniform scaling positioned horizontally from the left and vertically centered.</dd>
         *      <dt>xMidYMid (the default)</dt><dd>Force uniform scaling with the content centered.</dd>
         *      <dt>xMaxYMid</dt><dd>Force uniform scaling positioned horizontally from the right and vertically centered.</dd>
         *      <dt>xMinYMax</dt><dd>Force uniform scaling positioned horizontally from the left and vertically from the bottom.</dd>
         *      <dt>xMidYMax</dt><dd>Force uniform scaling horizontally centered and position vertically from the bottom.</dd>
         *      <dt>xMaxYMax</dt><dd>Force uniform scaling positioned horizontally from the right and vertically from the bottom.</dd>
         *  </dl>
         *
         * @config preserveAspectRatio
         * @type String
         * @default xMidYMid
         */
        preserveAspectRatio: {
            value: "xMidYMid"
        },

        /**
         * The contentBounds will resize to greater values but not smaller values. (for performance)
         * When resizing the contentBounds down is desirable, set the resizeDown value to true.
         *
         * @config resizeDown
         * @type Boolean
         */
        resizeDown: {
            value: false
        },

    	/**
    	 * Indicates the x-coordinate for the instance.
    	 *
    	 * @config x
    	 * @type Number
    	 */
        x: {
            getter: function()
            {
                return this._x;
            },

            setter: function(val)
            {
                this._x = val;
                if(this._node)
                {
                    this._node.style.left = val + "px";
                }
                return val;
            }
        },

    	/**
    	 * Indicates the y-coordinate for the instance.
    	 *
    	 * @config y
    	 * @type Number
    	 */
        y: {
            getter: function()
            {
                return this._y;
            },

            setter: function(val)
            {
                this._y = val;
                if(this._node)
                {
                    this._node.style.top = val + "px";
                }
                return val;
            }
        },

        /**
         * Indicates whether or not the instance will automatically redraw after a change is made to a shape.
         * This property will get set to false when batching operations.
         *
         * @config autoDraw
         * @type Boolean
         * @default true
         * @private
         */
        autoDraw: {
            value: true
        },

    	/**
    	 * Indicates whether the `Graphic` and its children are visible.
    	 *
    	 * @config visible
    	 * @type Boolean
    	 */
        visible: {
            value: true,

            setter: function(val)
            {
                this._toggleVisible(val);
                return val;
            }
        }
    };

    Y.extend(CanvasGraphic, Y.GraphicBase, {
        /**
         * Sets the value of an attribute.
         *
         * @method set
         * @param {String|Object} name The name of the attribute. Alternatively, an object of key value pairs can
         * be passed in to set multiple attributes at once.
         * @param {Any} value The value to set the attribute to. This value is ignored if an object is received as
         * the name param.
         */
    	set: function()
    	{
    		var host = this,
                attr = arguments[0],
                redrawAttrs = {
                    autoDraw: true,
                    autoSize: true,
                    preserveAspectRatio: true,
                    resizeDown: true
                },
                key,
                forceRedraw = false;
    		AttributeLite.prototype.set.apply(host, arguments);
            if(host._state.autoDraw === true && Y.Object.size(this._shapes) > 0)
            {
                if(Y_LANG.isString && redrawAttrs[attr])
                {
                    forceRedraw = true;
                }
                else if(Y_LANG.isObject(attr))
                {
                    for(key in redrawAttrs)
                    {
                        if(redrawAttrs.hasOwnProperty(key) && attr[key])
                        {
                            forceRedraw = true;
                            break;
                        }
                    }
                }
            }
            if(forceRedraw)
            {
                host._redraw();
            }
    	},

        /**
         * Storage for `x` attribute.
         *
         * @property _x
         * @type Number
         * @private
         */
        _x: 0,

        /**
         * Storage for `y` attribute.
         *
         * @property _y
         * @type Number
         * @private
         */
        _y: 0,

        /**
         * Gets the current position of the graphic instance in page coordinates.
         *
         * @method getXY
         * @return Array The XY position of the shape.
         */
        getXY: function()
        {
            var node = Y.one(this._node),
                xy;
            if(node)
            {
                xy = node.getXY();
            }
            return xy;
        },

    	/**
         * Initializes the class.
         *
         * @method initializer
         * @param {Object} config Optional attributes
         * @private
         */
        initializer: function() {
            var render = this.get("render"),
                visibility = this.get("visible") ? "visible" : "hidden",
                w = this.get("width") || 0,
                h = this.get("height") || 0;
            this._shapes = {};
            this._redrawQueue = {};
    		this._contentBounds = {
                left: 0,
                top: 0,
                right: 0,
                bottom: 0
            };
            this._node = DOCUMENT.createElement('div');
            this._node.style.position = "absolute";
            this._node.style.visibility = visibility;
            this.set("width", w);
            this.set("height", h);
            if(render)
            {
                this.render(render);
            }
        },

        /**
         * Adds the graphics node to the dom.
         *
         * @method render
         * @param {HTMLElement} parentNode node in which to render the graphics node into.
         */
        render: function(render) {
            var parentNode = Y.one(render),
                node = this._node,
                w = this.get("width") || parseInt(parentNode.getComputedStyle("width"), 10),
                h = this.get("height") || parseInt(parentNode.getComputedStyle("height"), 10);
            parentNode = parentNode || DOCUMENT.body;
            parentNode.appendChild(node);
            node.style.display = "block";
            node.style.position = "absolute";
            node.style.left = "0px";
            node.style.top = "0px";
            this.set("width", w);
            this.set("height", h);
            this.parentNode = parentNode;
            return this;
        },

        /**
         * Removes all nodes.
         *
         * @method destroy
         */
        destroy: function()
        {
            this.removeAllShapes();
            if(this._node)
            {
                this._removeChildren(this._node);
                Y.one(this._node).destroy();
            }
        },

        /**
         * Generates a shape instance by type.
         *
         * @method addShape
         * @param {Object} cfg attributes for the shape
         * @return Shape
         */
        addShape: function(cfg)
        {
            cfg.graphic = this;
            if(!this.get("visible"))
            {
                cfg.visible = false;
            }
            var ShapeClass = this._getShapeClass(cfg.type),
                shape = new ShapeClass(cfg);
            this._appendShape(shape);
            return shape;
        },

        /**
         * Adds a shape instance to the graphic instance.
         *
         * @method _appendShape
         * @param {Shape} shape The shape instance to be added to the graphic.
         * @private
         */
        _appendShape: function(shape)
        {
            var node = shape.node,
                parentNode = this._frag || this._node;
            if(this.get("autoDraw"))
            {
                parentNode.appendChild(node);
            }
            else
            {
                this._getDocFrag().appendChild(node);
            }
        },

        /**
         * Removes a shape instance from from the graphic instance.
         *
         * @method removeShape
         * @param {Shape|String} shape The instance or id of the shape to be removed.
         */
        removeShape: function(shape)
        {
            if(!(shape instanceof CanvasShape))
            {
                if(Y_LANG.isString(shape))
                {
                    shape = this._shapes[shape];
                }
            }
            if(shape && shape instanceof CanvasShape)
            {
                shape._destroy();
                delete this._shapes[shape.get("id")];
            }
            if(this.get("autoDraw"))
            {
                this._redraw();
            }
            return shape;
        },

        /**
         * Removes all shape instances from the dom.
         *
         * @method removeAllShapes
         */
        removeAllShapes: function()
        {
            var shapes = this._shapes,
                i;
            for(i in shapes)
            {
                if(shapes.hasOwnProperty(i))
                {
                    shapes[i].destroy();
                }
            }
            this._shapes = {};
        },

        /**
         * Clears the graphics object.
         *
         * @method clear
         */
        clear: function() {
            this.removeAllShapes();
        },

        /**
         * Removes all child nodes.
         *
         * @method _removeChildren
         * @param {HTMLElement} node
         * @private
         */
        _removeChildren: function(node)
        {
            if(node && node.hasChildNodes())
            {
                var child;
                while(node.firstChild)
                {
                    child = node.firstChild;
                    this._removeChildren(child);
                    node.removeChild(child);
                }
            }
        },

        /**
         * Toggles visibility
         *
         * @method _toggleVisible
         * @param {Boolean} val indicates visibilitye
         * @private
         */
        _toggleVisible: function(val)
        {
            var i,
                shapes = this._shapes,
                visibility = val ? "visible" : "hidden";
            if(shapes)
            {
                for(i in shapes)
                {
                    if(shapes.hasOwnProperty(i))
                    {
                        shapes[i].set("visible", val);
                    }
                }
            }
            if(this._node)
            {
                this._node.style.visibility = visibility;
            }
        },

        /**
         * Returns a shape class. Used by `addShape`.
         *
         * @method _getShapeClass
         * @param {Shape | String} val Indicates which shape class.
         * @return Function
         * @private
         */
        _getShapeClass: function(val)
        {
            var shape = this._shapeClass[val];
            if(shape)
            {
                return shape;
            }
            return val;
        },

        /**
         * Look up for shape classes. Used by `addShape` to retrieve a class for instantiation.
         *
         * @property _shapeClass
         * @type Object
         * @private
         */
        _shapeClass: {
            circle: Y.CanvasCircle,
            rect: Y.CanvasRect,
            path: Y.CanvasPath,
            ellipse: Y.CanvasEllipse,
            pieslice: Y.CanvasPieSlice
        },

        /**
         * Returns a shape based on the id of its dom node.
         *
         * @method getShapeById
         * @param {String} id Dom id of the shape's node attribute.
         * @return Shape
         */
        getShapeById: function(id)
        {
            var shape = this._shapes[id];
            return shape;
        },

    	/**
    	 * Allows for creating multiple shapes in order to batch appending and redraw operations.
    	 *
    	 * @method batch
    	 * @param {Function} method Method to execute.
    	 */
        batch: function(method)
        {
            var autoDraw = this.get("autoDraw");
            this.set("autoDraw", false);
            method();
            this.set("autoDraw", autoDraw);
        },

        /**
         * Returns a document fragment to for attaching shapes.
         *
         * @method _getDocFrag
         * @return DocumentFragment
         * @private
         */
        _getDocFrag: function()
        {
            if(!this._frag)
            {
                this._frag = DOCUMENT.createDocumentFragment();
            }
            return this._frag;
        },

        /**
         * Redraws all shapes.
         *
         * @method _redraw
         * @private
         */
        _redraw: function()
        {
            var autoSize = this.get("autoSize"),
                preserveAspectRatio = this.get("preserveAspectRatio"),
                box = this.get("resizeDown") ? this._getUpdatedContentBounds() : this._contentBounds,
                contentWidth,
                contentHeight,
                w,
                h,
                xScale,
                yScale,
                translateX = 0,
                translateY = 0,
                matrix,
                node = this.get("node");
            if(autoSize)
            {
                if(autoSize === "sizeContentToGraphic")
                {
                    contentWidth = box.right - box.left;
                    contentHeight = box.bottom - box.top;
                    w = parseFloat(Y_DOM.getComputedStyle(node, "width"));
                    h = parseFloat(Y_DOM.getComputedStyle(node, "height"));
                    matrix = new Y.Matrix();
                    if(preserveAspectRatio === "none")
                    {
                        xScale = w/contentWidth;
                        yScale = h/contentHeight;
                    }
                    else
                    {
                        if(contentWidth/contentHeight !== w/h)
                        {
                            if(contentWidth * h/contentHeight > w)
                            {
                                xScale = yScale = w/contentWidth;
                                translateY = this._calculateTranslate(preserveAspectRatio.slice(5).toLowerCase(), contentHeight * w/contentWidth, h);
                            }
                            else
                            {
                                xScale = yScale = h/contentHeight;
                                translateX = this._calculateTranslate(preserveAspectRatio.slice(1, 4).toLowerCase(), contentWidth * h/contentHeight, w);
                            }
                        }
                    }
                    Y_DOM.setStyle(node, "transformOrigin", "0% 0%");
                    translateX = translateX - (box.left * xScale);
                    translateY = translateY - (box.top * yScale);
                    matrix.translate(translateX, translateY);
                    matrix.scale(xScale, yScale);
                    Y_DOM.setStyle(node, "transform", matrix.toCSSText());
                }
                else
                {
                    this.set("width", box.right);
                    this.set("height", box.bottom);
                }
            }
            if(this._frag)
            {
                this._node.appendChild(this._frag);
                this._frag = null;
            }
        },

        /**
         * Determines the value for either an x or y value to be used for the <code>translate</code> of the Graphic.
         *
         * @method _calculateTranslate
         * @param {String} position The position for placement. Possible values are min, mid and max.
         * @param {Number} contentSize The total size of the content.
         * @param {Number} boundsSize The total size of the Graphic.
         * @return Number
         * @private
         */
        _calculateTranslate: function(position, contentSize, boundsSize)
        {
            var ratio = boundsSize - contentSize,
                coord;
            switch(position)
            {
                case "mid" :
                    coord = ratio * 0.5;
                break;
                case "max" :
                    coord = ratio;
                break;
                default :
                    coord = 0;
                break;
            }
            return coord;
        },

        /**
         * Adds a shape to the redraw queue and calculates the contentBounds. Used internally
         * by `Shape` instances.
         *
         * @method addToRedrawQueue
         * @param Shape shape The shape instance to add to the queue
         * @protected
         */
        addToRedrawQueue: function(shape)
        {
            var shapeBox,
                box;
            this._shapes[shape.get("id")] = shape;
            if(!this.get("resizeDown"))
            {
                shapeBox = shape.getBounds();
                box = this._contentBounds;
                box.left = box.left < shapeBox.left ? box.left : shapeBox.left;
                box.top = box.top < shapeBox.top ? box.top : shapeBox.top;
                box.right = box.right > shapeBox.right ? box.right : shapeBox.right;
                box.bottom = box.bottom > shapeBox.bottom ? box.bottom : shapeBox.bottom;
                this._contentBounds = box;
            }
            if(this.get("autoDraw"))
            {
                this._redraw();
            }
        },

        /**
         * Recalculates and returns the `contentBounds` for the `Graphic` instance.
         *
         * @method _getUpdatedContentBounds
         * @return {Object}
         * @private
         */
        _getUpdatedContentBounds: function()
        {
            var bounds,
                i,
                shape,
                queue = this._shapes,
                box = {};
            for(i in queue)
            {
                if(queue.hasOwnProperty(i))
                {
                    shape = queue[i];
                    bounds = shape.getBounds();
                    box.left = Y_LANG.isNumber(box.left) ? Math.min(box.left, bounds.left) : bounds.left;
                    box.top = Y_LANG.isNumber(box.top) ? Math.min(box.top, bounds.top) : bounds.top;
                    box.right = Y_LANG.isNumber(box.right) ? Math.max(box.right, bounds.right) : bounds.right;
                    box.bottom = Y_LANG.isNumber(box.bottom) ? Math.max(box.bottom, bounds.bottom) : bounds.bottom;
                }
            }
            box.left = Y_LANG.isNumber(box.left) ? box.left : 0;
            box.top = Y_LANG.isNumber(box.top) ? box.top : 0;
            box.right = Y_LANG.isNumber(box.right) ? box.right : 0;
            box.bottom = Y_LANG.isNumber(box.bottom) ? box.bottom : 0;
            this._contentBounds = box;
            return box;
        },

        /**
         * Inserts shape on the top of the tree.
         *
         * @method _toFront
         * @param {CanvasShape} Shape to add.
         * @private
         */
        _toFront: function(shape)
        {
            var contentNode = this.get("node");
            if(shape instanceof Y.CanvasShape)
            {
                shape = shape.get("node");
            }
            if(contentNode && shape)
            {
                contentNode.appendChild(shape);
            }
        },

        /**
         * Inserts shape as the first child of the content node.
         *
         * @method _toBack
         * @param {CanvasShape} Shape to add.
         * @private
         */
        _toBack: function(shape)
        {
            var contentNode = this.get("node"),
                targetNode;
            if(shape instanceof Y.CanvasShape)
            {
                shape = shape.get("node");
            }
            if(contentNode && shape)
            {
                targetNode = contentNode.firstChild;
                if(targetNode)
                {
                    contentNode.insertBefore(shape, targetNode);
                }
                else
                {
                    contentNode.appendChild(shape);
                }
            }
        }
    });

    Y.CanvasGraphic = CanvasGraphic;