1 /****************************************************************************
  2  Copyright (c) 2010-2012 cocos2d-x.org
  3  Copyright (c) 2008-2010 Ricardo Quesada
  4  Copyright (c) 2011      Zynga Inc.
  5  Copyright (c) 2008-2009 Jason Booth
  6 
  7  http://www.cocos2d-x.org
  8 
  9  Permission is hereby granted, free of charge, to any person obtaining a copy
 10  of this software and associated documentation files (the "Software"), to deal
 11  in the Software without restriction, including without limitation the rights
 12  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 13  copies of the Software, and to permit persons to whom the Software is
 14  furnished to do so, subject to the following conditions:
 15 
 16  The above copyright notice and this permission notice shall be included in
 17  all copies or substantial portions of the Software.
 18 
 19  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 20  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 21  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 22  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 23  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 24  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 25  THE SOFTWARE.
 26  ****************************************************************************/
 27 
 28 /**
 29  * cc.MotionStreak manages a Ribbon based on it's motion in absolute space.<br/>
 30  * You construct it with a fadeTime, minimum segment size, texture path, texture<br/>
 31  * length and color. The fadeTime controls how long it takes each vertex in<br/>
 32  * the streak to fade out, the minimum segment size it how many pixels the<br/>
 33  * streak will move before adding a new ribbon segment, and the texture<br/>
 34  * length is the how many pixels the texture is stretched across. The texture<br/>
 35  * is vertically aligned along the streak segment.
 36  * @class
 37  * @extends cc.Node
 38  */
 39 cc.MotionStreak = cc.Node.extend(/** @lends cc.MotionStreak# */{
 40     _segThreshold:0,
 41     _width:0,
 42     _lastLocation:cc.PointZero(),
 43 
 44     /**
 45      * @type cc.Ribbon
 46      */
 47     _ribbon:null,
 48 
 49     /**
 50      * Ribbon used by MotionStreak (weak reference)
 51      * @return {cc.Ribbon}
 52      */
 53     getRibbon:function () {
 54         return this._ribbon;
 55     },
 56 
 57     /**
 58      * @return {cc.Texture2D}
 59      */
 60     getTexture:function () {
 61         return this._ribbon.getTexture();
 62     },
 63 
 64     /**
 65      * @param {cc.Texture2D} texture
 66      */
 67     setTexture:function (texture) {
 68         this._ribbon.setTexture(texture);
 69     },
 70 
 71     /**
 72      * @return {cc.BlendFunc}
 73      */
 74     getBlendFunc:function () {
 75         return this._ribbon.getBlendFunc();
 76     },
 77 
 78     /**
 79      * @param {Number} src
 80      * @param {Number} dst
 81      */
 82     setBlendFunc:function (src, dst) {
 83         this._ribbon.setBlendFunc(src, dst);
 84     },
 85 
 86     /**
 87      * Constructor
 88      */
 89     ctor:function () {
 90         this._super();
 91     },
 92 
 93     /**
 94      * initializes a MotionStreak. The file will be loaded using the TextureMgr.
 95      * @param {Number} fade
 96      * @param {Number} seg
 97      * @param {String} imagePath
 98      * @param {Number} width
 99      * @param {Number} length
100      * @param {cc.Color4B} color
101      * @return {Boolean}
102      */
103     initWithFade:function (fade, seg, imagePath, width, length, color) {
104         this._segThreshold = seg;
105         this._width = width;
106         this._lastLocation = cc.PointZero();
107         this._ribbon = cc.Ribbon.create(this._width, imagePath, length, color, fade);
108         this.addChild(this._ribbon);
109 
110         // update ribbon position. Use schedule:interval and not scheduleUpdated. (cocos2d-iphone)issue #1075
111         this.schedule(this.update, 0);
112         return true;
113     },
114 
115     /**
116      * polling function
117      */
118     update:function (delta) {
119         var location = this.convertToWorldSpace(cc.PointZero());
120         this._ribbon.setPosition(cc.p(-1 * location.x, -1 * location.y));
121         var len = cc.pLength(cc.pSub(this._lastLocation, location));
122         if (len > this._segThreshold) {
123             this._ribbon.addPointAt(location, this._width);
124             this._lastLocation = location;
125         }
126         this._ribbon.update(delta);
127     }
128 });
129 
130 /**
131  * creates the a MotionStreak. The image will be loaded using the TextureMgr.
132  * @param {Number} fade time to fade
133  * @param {Number} seg minimum segment size
134  * @param {String} imagePath texture path
135  * @param {Number} width texture width
136  * @param {Number} length texture length
137  * @param {cc.Color4B} color color
138  * @return {cc.MotionStreak}
139  */
140 cc.MotionStreak.create = function (fade, seg, imagePath, width, length, color) {
141     var ret = new cc.MotionStreak();
142     if (ret && ret.initWithFade(fade, seg, imagePath, width, length, color)) {
143         return ret;
144     }
145     return null;
146 };
147