Hilo/docs/api-en/code/view/Sprite.js
2016-12-14 14:40:55 +08:00

251 lines
8.1 KiB
JavaScript

/**
* Hilo
* Copyright 2015 alibaba.com
* Licensed under the MIT License
*/
/**
* <iframe src='../../../examples/Sprite.html?noHeader' width = '550' height = '400' scrolling='no'></iframe>
* <br/>
* @class Sprite animation class.
* @augments View
* @module hilo/view/Sprite
* @requires hilo/core/Hilo
* @requires hilo/core/Class
* @requires hilo/view/View
* @requires hilo/view/Drawable
* @param properties Properties parameters for creating object, include all writable properties of this class, also include:
* <ul>
* <li><b>frames</b> - Sprite animation frames data object.</li>
* </ul>
* @property {number} currentFrame Current showing frame index, range from 0, readoly!
* @property {boolean} paused Is sprite paused, default value is false.
* @property {boolean} loop Is sprite play in loop, default value is false.
* @property {boolean} timeBased Is sprite animate base on time, default value is false (base on frame).
* @property {number} interval Interval between sprite animation frames. If timeBased is true, measured in ms, otherwise, measured in frames.
*/
var Sprite = Class.create(/** @lends Sprite.prototype */{
Extends: View,
constructor: function(properties){
properties = properties || {};
this.id = this.id || properties.id || Hilo.getUid("Sprite");
Sprite.superclass.constructor.call(this, properties);
this._frames = [];
this._frameNames = {};
this.drawable = new Drawable();
if(properties.frames) this.addFrame(properties.frames);
},
_frames: null, //所有帧的集合 Collection of all frames
_frameNames: null, //带名字name的帧的集合 Collection of frames that with name
_frameElapsed: 0, //当前帧持续的时间或帧数 Elapsed time of current frame.
_firstRender: true, //标记是否是第一次渲染 Is the first render.
paused: false,
loop: true,
timeBased: false,
interval: 1,
currentFrame: 0, //当前帧的索引 Index of current frame
/**
* Return the total amount of sprite animation frames.
* @returns {Uint} The total amount of frames.
*/
getNumFrames: function(){
return this._frames ? this._frames.length : 0;
},
/**
* Add frame into sprite.
* @param {Object} frame Frames to add into.
* @param {Int} startIndex The index to start adding frame, if is not given, add at the end of sprite.
* @returns {Sprite} Sprite itself.
*/
addFrame: function(frame, startIndex){
var start = startIndex != null ? startIndex : this._frames.length;
if(frame instanceof Array){
for(var i = 0, len = frame.length; i < len; i++){
this.setFrame(frame[i], start + i);
}
}else{
this.setFrame(frame, start);
}
return this;
},
/**
* Set the frame on the given index.
* @param {Object} frame The frame data to set on that index.
* @param {Int} index Index of the frame to set.
* @returns {Sprite} Sprite itself.
*/
setFrame: function(frame, index){
var frames = this._frames,
total = frames.length;
index = index < 0 ? 0 : index > total ? total : index;
frames[index] = frame;
if(frame.name) this._frameNames[frame.name] = frame;
if(index == 0 && !this.width || !this.height){
this.width = frame.rect[2];
this.height = frame.rect[3];
}
return this;
},
/**
* Get the frame of given parameter from sprite.
* @param {Object} indexOrName The index or name of the frame.
* @returns {Object} The sprite object.
*/
getFrame: function(indexOrName){
if(typeof indexOrName === 'number'){
var frames = this._frames;
if(indexOrName < 0 || indexOrName >= frames.length) return null;
return frames[indexOrName];
}
return this._frameNames[indexOrName];
},
/**
* Get frame index from sprite.
* @param {Object} frameValue Index or name of the frame.
* @returns {Object} Sprite frame object.
*/
getFrameIndex: function(frameValue){
var frames = this._frames,
total = frames.length,
index = -1;
if(typeof frameValue === 'number'){
index = frameValue;
}else{
var frame = typeof frameValue === 'string' ? this._frameNames[frameValue] : frameValue;
if(frame){
for(var i = 0; i < total; i++){
if(frame === frames[i]){
index = i;
break;
}
}
}
}
return index;
},
/**
* Play sprite.
* @returns {Sprite} The Sprite object.
*/
play: function(){
this.paused = false;
return this;
},
/**
* Pause playing sprite.
* @returns {Sprite} The Sprite object.
*/
stop: function(){
this.paused = true;
return this;
},
/**
* Jump to an assigned frame.
* @param {Object} indexOrName Index or name of an frame to jump to.
* @param {Boolean} pause Does pause after jumping to the new index.
* @returns {Sprite} The Sprite object.
*/
goto: function(indexOrName, pause){
var total = this._frames.length,
index = this.getFrameIndex(indexOrName);
this.currentFrame = index < 0 ? 0 : index >= total ? total - 1 : index;
this.paused = pause;
this._firstRender = true;
return this;
},
/**
* Render function.
* @private
*/
_render: function(renderer, delta){
var lastFrameIndex = this.currentFrame, frameIndex;
if(this._firstRender){
frameIndex = lastFrameIndex;
this._firstRender = false;
}else{
frameIndex = this._nextFrame(delta);
}
if(frameIndex != lastFrameIndex){
this.currentFrame = frameIndex;
var callback = this._frames[frameIndex].callback;
callback && callback.call(this);
}
//NOTE: it will be deprecated, don't use it.
if(this.onEnterFrame) this.onEnterFrame(frameIndex);
this.drawable.init(this._frames[frameIndex]);
Sprite.superclass._render.call(this, renderer, delta);
},
/**
* @private
*/
_nextFrame: function(delta){
var frames = this._frames,
total = frames.length,
frameIndex = this.currentFrame,
frame = frames[frameIndex],
duration = frame.duration || this.interval,
elapsed = this._frameElapsed;
//calculate the current frame elapsed frames/time
var value = (frameIndex == 0 && !this.drawable) ? 0 : elapsed + (this.timeBased ? delta : 1);
elapsed = this._frameElapsed = value < duration ? value : 0;
if(frame.stop || !this.loop && frameIndex >= total - 1){
this.stop();
}
if(!this.paused && elapsed == 0){
if(frame.next != null){
//jump to the specified frame
frameIndex = this.getFrameIndex(frame.next);
}else if(frameIndex >= total - 1){
//at the end of the frames, go back to first frame
frameIndex = 0;
}else if(this.drawable){
//normal go forward to next frame
frameIndex++;
}
}
return frameIndex;
},
/**
* Set a callback on an assigned frame. Every time assigned frame is played, invoke the callback function. If callback is empty, callback function will be removed.
* @param {Int|String} frame Index or name of the assigned frame.
* @param {Function} callback Callback function.
* @returns {Sprite} The Sprite object.
*/
setFrameCallback: function(frame, callback){
frame = this.getFrame(frame);
if(frame) frame.callback = callback;
return this;
},
/**
* Callback function on when sprite enter a new frame. default value is null. Note: this function is obsolete, use addFrameCallback funciton instead.
* @type Function
* @deprecated
*/
onEnterFrame: null
});