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/*
* Bitmap by Grant Skinner. Dec 5, 2010
* Visit http://easeljs.com/ for documentation, updates and examples.
*
*
* Copyright (c) 2010 Grant Skinner
* 
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
* 
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/

/**
* The Easel Javascript library provides a retained graphics mode for canvas 
* including a full, hierarchical display list, a core interaction model, and 
* helper classes to make working with Canvas much easier.
* @module EaselJS
**/

(function(window) {

/**
* A Bitmap represents an Image, Canvas, or Video in the display list.
* @class Bitmap
* @extends DisplayObject
* @constructor
* @param {Image | HTMLCanvasElement | HTMLVideoElement} image The Image, Canvas, or Video to render to the display list.
**/
Bitmap = function(image) {
  this.initialize(image);
}
var p = Bitmap.prototype = new DisplayObject();

	// public properties:
	/**
	* The image to render. This can be an Image, a Canvas, or a Video.
	* @property image
	* @type Image | HTMLCanvasElement | HTMLVideoElement
	**/
	p.image = null;
	
	/**
	* Whether or not the Bitmap should be draw to the canvas at whole pixel coordinates.
	* @property snapToPixel
	* @type Boolean
	* @default true
	**/
	p.snapToPixel = true;
	
	// constructor:

	/**
	* @property DisplayObject_initialize
	* @type Function
    * @private
	**/
	p.DisplayObject_initialize = p.initialize;

	/** 
	* Initialization method.
	* @method initialize
	* @protected
	*/
	p.initialize = function(image) {
		this.DisplayObject_initialize();
		this.image = image;
	}
	
// public methods:

	/**
	* Returns true or false indicating whether the display object would be visible if drawn to a canvas.
	* This does not account for whether it would be visible within the boundaries of the stage.
	* NOTE: This method is mainly for internal use, though it may be useful for advanced uses.
	* @method isVisible
	* @return {Boolean} Boolean indicating whether the display object would be visible if drawn to a canvas
	**/
	p.isVisible = function() {
		return this.visible && this.alpha > 0 && this.scaleX != 0 && this.scaleY != 0 && this.image && (this.image.complete || this.image.getContext);
	}

	/**
	* @property DisplayObject_draw
	* @type Function
	* @private
	**/
	p.DisplayObject_draw = p.draw;
	
	/**
	* Draws the display object into the specified context ignoring it's visible, alpha, shadow, and transform.
	* Returns true if the draw was handled (useful for overriding functionality).
	* NOTE: This method is mainly for internal use, though it may be useful for advanced uses.
	* @method draw
	* @param {CanvasRenderingContext2D} ctx The canvas 2D context object to draw into.
	* @param {Boolean} ignoreCache Indicates whether the draw operation should ignore any current cache. 
	* For example, used for drawing the cache (to prevent it from simply drawing an existing cache back
	* into itself).
	**/
	p.draw = function(ctx, ignoreCache) {
		if (this.DisplayObject_draw(ctx, ignoreCache)) { return true; }
		ctx.drawImage(this.image, 0, 0);
		return true;
	}
	
	//Note, the doc sections below document using the specified APIs (from DisplayObject)  from
	//Bitmap. This is why they have no method implementations.
	
	/**
	* Because the content of a Bitmap is already in a simple format, cache is unnecessary for Bitmap instances.
	* You should not cache Bitmap instances as it can degrade performance.
	* @method cache
	**/
	
	/**
	* Because the content of a Bitmap is already in a simple format, cache is unnecessary for Bitmap instances.
	* You should not cache Bitmap instances as it can degrade performance.
	* @method updateCache
	**/
	
	/**
	* Because the content of a Bitmap is already in a simple format, cache is unnecessary for Bitmap instances.
	* You should not cache Bitmap instances as it can degrade performance.
	* @method uncache
	**/
	
	/**
	* Returns a clone of the Bitmap instance.
	* @method clone
	* @return {Bitmap} a clone of the Bitmap instance.
	**/
	p.clone = function() {
		var o = new Bitmap(this.image);
		this.cloneProps(o);
		return o;
	}
	
	/**
	* Returns a string representation of this object.
	* @method toString
	* @return {String} a string representation of the instance.
	**/
	p.toString = function() {
		return "[Bitmap (name="+  this.name +")]";
	}

window.Bitmap = Bitmap;
}(window));