tv_xiaoyouxi/games/dwy/cocos2d-html5-v2.2.3/cocos2d/CCTextureAtlas.js

/****************************************************************************
 Copyright (c) 2010-2012 cocos2d-x.org
 Copyright (c) 2008-2010 Ricardo Quesada
 Copyright (c) 2011      Zynga Inc.

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/**
 * <p>A class that implements a Texture Atlas. <br />
 * Supported features: <br />
 * The atlas file can be a PNG, JPG. <br />
 * Quads can be updated in runtime <br />
 * Quads can be added in runtime <br />
 * Quads can be removed in runtime <br />
 * Quads can be re-ordered in runtime <br />
 * The TextureAtlas capacity can be increased or decreased in runtime.</p>
 * @class
 * @extends cc.Class
 */
cc.TextureAtlas = cc.Class.extend(/** @lends cc.TextureAtlas# */{
    _indices:null,
    //0: vertex  1: indices
    _buffersVBO:null,
    //indicates whether or not the array buffer of the VBO needs to be updated
    _dirty:false,
    _capacity:0,
    _texture:null,

    _quads:null,
    _quadsArrayBuffer:null,
    _quadsWebBuffer:null,
    _quadsReader:null,

    ctor:function () {
        this._buffersVBO = [];
    },

    /**
     * Quantity of quads that are going to be drawn.
     * @return {Number}
     */
    getTotalQuads:function () {
        //return this._quads.length;
        return this._totalQuads;
    },

    /**
     * Quantity of quads that can be stored with the current texture atlas size
     * @return {Number}
     */
    getCapacity:function () {
        return this._capacity;
    },

    /**
     * Texture of the texture atlas
     * @return {Image}
     */
    getTexture:function () {
        return this._texture;
    },

    /**
     * @param {Image} texture
     */
    setTexture:function (texture) {
        this._texture = texture;
    },

    /**
     * specify if the array buffer of the VBO needs to be updated
     * @param {Boolean} dirty
     */
    setDirty:function (dirty) {
        this._dirty = dirty;
    },

    /**
     * whether or not the array buffer of the VBO needs to be updated
     * @returns {boolean}
     */
    isDirty:function () {
        return this._dirty;
    },

    /**
     * Quads that are going to be rendered
     * @return {Array}
     */
    getQuads:function () {
        return this._quads;
    },

    /**
     * @param {Array} quads
     */
    setQuads:function (quads) {
        this._quads = quads;
        //TODO need re-binding
    },

    _copyQuadsToTextureAtlas:function(quads, index){
        if(!quads)
            return;

        for(var i = 0; i < quads.length ; i++)
            this._setQuadToArray(quads[i], index + i);
    },

    _setQuadToArray: function (quad, index) {
        var locQuads = this._quads;
        if (!locQuads[index]) {
            locQuads[index] = new cc.V3F_C4B_T2F_Quad(quad.tl, quad.bl, quad.tr, quad.br, this._quadsArrayBuffer, index * cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT);
            return;
        }
        locQuads[index].bl = quad.bl;
        locQuads[index].br = quad.br;
        locQuads[index].tl = quad.tl;
        locQuads[index].tr = quad.tr;
    },

    /**
     * Description
     * @return {String}
     */
    description:function () {
        return '<cc.TextureAtlas | totalQuads =' + this._totalQuads + '>';
    },

    _setupIndices:function () {
        if (this._capacity === 0)
            return;
        var locIndices = this._indices, locCapacity = this._capacity;
        for (var i = 0; i < locCapacity; i++) {
            if (cc.TEXTURE_ATLAS_USE_TRIANGLE_STRIP) {
                locIndices[i * 6 + 0] = i * 4 + 0;
                locIndices[i * 6 + 1] = i * 4 + 0;
                locIndices[i * 6 + 2] = i * 4 + 2;
                locIndices[i * 6 + 3] = i * 4 + 1;
                locIndices[i * 6 + 4] = i * 4 + 3;
                locIndices[i * 6 + 5] = i * 4 + 3;
            } else {
                locIndices[i * 6 + 0] = i * 4 + 0;
                locIndices[i * 6 + 1] = i * 4 + 1;
                locIndices[i * 6 + 2] = i * 4 + 2;

                // inverted index. issue #179
                locIndices[i * 6 + 3] = i * 4 + 3;
                locIndices[i * 6 + 4] = i * 4 + 2;
                locIndices[i * 6 + 5] = i * 4 + 1;
            }
        }
    },

    _setupVBO:function () {
        var gl = cc.renderContext;
        //create WebGLBuffer
        this._buffersVBO[0] = gl.createBuffer();
        this._buffersVBO[1] = gl.createBuffer();

        this._quadsWebBuffer = gl.createBuffer();
        this._mapBuffers();
    },

    _mapBuffers:function () {
        var gl = cc.renderContext;

        gl.bindBuffer(gl.ARRAY_BUFFER, this._quadsWebBuffer);
        gl.bufferData(gl.ARRAY_BUFFER, this._quadsArrayBuffer, gl.DYNAMIC_DRAW);

        gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, this._buffersVBO[1]);
        gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, this._indices, gl.STATIC_DRAW);

        //cc.CHECK_GL_ERROR_DEBUG();
    },

    /**
     * <p>Initializes a TextureAtlas with a filename and with a certain capacity for Quads.<br />
     * The TextureAtlas capacity can be increased in runtime.<br />
     * WARNING: Do not reinitialize the TextureAtlas because it will leak memory. </p>
     * @param {String} file
     * @param {Number} capacity
     * @return {Boolean}
     * @example
     * //example
     * var textureAtlas = new cc.TextureAtlas();
     * textureAtlas.initWithTexture("hello.png", 3);
     */
    initWithFile:function (file, capacity) {
        // retained in property
        var texture = cc.TextureCache.getInstance().addImage(file);
        if (texture)
            return this.initWithTexture(texture, capacity);
        else {
            cc.log("cocos2d: Could not open file: " + file);
            return false;
        }
    },

    /**
     * <p>Initializes a TextureAtlas with a previously initialized Texture2D object, and<br />
     * with an initial capacity for Quads.<br />
     * The TextureAtlas capacity can be increased in runtime.<br />
     * WARNING: Do not reinitialize the TextureAtlas because it will leak memory</p>
     * @param {Image} texture
     * @param {Number} capacity
     * @return {Boolean}
     * @example
     * //example
     * var texture = cc.TextureCache.getInstance().addImage("hello.png");
     * var textureAtlas = new cc.TextureAtlas();
     * textureAtlas.initWithTexture(texture, 3);
     */
    initWithTexture:function (texture, capacity) {
        if(!texture)
            throw "cc.TextureAtlas.initWithTexture():texture should be non-null";

        capacity = 0 | (capacity);
        this._capacity = capacity;
        this._totalQuads = 0;

        // retained in property
        this._texture = texture;

        // Re-initialization is not allowed
        this._quads = [];
        this._indices = new Uint16Array(capacity * 6);
        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        this._quadsArrayBuffer = new ArrayBuffer(quadSize * capacity);
        this._quadsReader = new Uint8Array(this._quadsArrayBuffer);

        if (!( this._quads && this._indices) && capacity > 0)
            return false;

        var locQuads = this._quads;
        for(var i = 0; i< capacity; i++)
            locQuads[i] =new cc.V3F_C4B_T2F_Quad(null, null, null, null, this._quadsArrayBuffer, i * quadSize);

        this._setupIndices();
        this._setupVBO();
        this._dirty = true;
        return true;
    },

    /**
     * <p>Updates a Quad (texture, vertex and color) at a certain index <br />
     * index must be between 0 and the atlas capacity - 1 </p>
     * @param {cc.V2F_C4B_T2F_Quad} quad
     * @param {Number} index
     */
    updateQuad:function (quad, index) {
        if(!quad)
            throw "cc.TextureAtlas.updateQuad(): quad should be non-null";
        if((index < 0) || (index >= this._capacity))
            throw "cc.TextureAtlas.updateQuad(): Invalid index";
        this._totalQuads = Math.max(index + 1, this._totalQuads);
        this._setQuadToArray(quad, index);
        this._dirty = true;
    },

    /**
     * <p>Inserts a Quad (texture, vertex and color) at a certain index<br />
     * index must be between 0 and the atlas capacity - 1 </p>
     * @param {cc.V2F_C4B_T2F_Quad} quad
     * @param {Number} index
     */
    insertQuad:function (quad, index) {
        if(index >= this._capacity)
            throw "cc.TextureAtlas.insertQuad(): Invalid index";

        this._totalQuads++;
        if(this._totalQuads > this._capacity) {
            cc.log("cc.TextureAtlas.insertQuad(): invalid totalQuads");
            return;
        }
        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        // issue #575. index can be > totalQuads
        var remaining = (this._totalQuads-1) - index;
        var startOffset = index * quadSize;
        var moveLength = remaining * quadSize;
        this._quads[this._totalQuads -1] = new cc.V3F_C4B_T2F_Quad(null, null, null, null, this._quadsArrayBuffer, (this._totalQuads -1) * quadSize);
        this._quadsReader.set(this._quadsReader.subarray(startOffset, startOffset + moveLength), startOffset + quadSize);

        this._setQuadToArray(quad, index);
        this._dirty = true;
    },

    /**
     * <p>
     *      Inserts a c array of quads at a given index                                           <br />
     *      index must be between 0 and the atlas capacity - 1                                    <br />
     *      this method doesn't enlarge the array when amount + index > totalQuads                <br />
     * </p>
     * @param {Array} quads
     * @param {Number} index
     * @param {Number} amount
     */
    insertQuads:function (quads, index, amount) {
        amount = amount || quads.length;
        if((index + amount) > this._capacity)
            throw "cc.TextureAtlas.insertQuad(): Invalid index + amount";

        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        this._totalQuads += amount;
        if(this._totalQuads > this._capacity) {
            cc.log("cc.TextureAtlas.insertQuad(): invalid totalQuads");
            return;
        }

        // issue #575. index can be > totalQuads
        var remaining = (this._totalQuads-1) - index - amount;
        var startOffset = index * quadSize;
        var moveLength = remaining * quadSize;
        var lastIndex = (this._totalQuads-1)  - amount;

        var i;
        for(i = 0; i < amount;i++)
            this._quads[lastIndex + i] = new cc.V3F_C4B_T2F_Quad(null, null, null, null, this._quadsArrayBuffer, (this._totalQuads -1) * quadSize);
        this._quadsReader.set(this._quadsReader.subarray(startOffset, startOffset + moveLength), startOffset + quadSize * amount);
        for(i = 0; i < amount; i++)
            this._setQuadToArray(quads[i], index + i);

        this._dirty = true;
    },

    /**
     * <p>Removes the quad that is located at a certain index and inserts it at a new index <br />
     * This operation is faster than removing and inserting in a quad in 2 different steps</p>
     * @param {Number} fromIndex
     * @param {Number} newIndex
     */
    insertQuadFromIndex:function (fromIndex, newIndex) {
        if (fromIndex === newIndex)
            return;

        if(newIndex < 0 && newIndex >= this._totalQuads)
            throw "cc.TextureAtlas.insertQuadFromIndex(): Invalid newIndex";
        if(fromIndex < 0 && fromIndex >= this._totalQuads)
            throw "cc.TextureAtlas.insertQuadFromIndex(): Invalid fromIndex";

        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        var locQuadsReader = this._quadsReader;
        var sourceArr = locQuadsReader.subarray(fromIndex * quadSize,quadSize);
        var startOffset, moveLength;
        if(fromIndex > newIndex){
            startOffset = newIndex * quadSize;
            moveLength = (fromIndex - newIndex) * quadSize;
            locQuadsReader.set(locQuadsReader.subarray(startOffset, startOffset + moveLength),startOffset + quadSize);
            locQuadsReader.set(sourceArr,startOffset);
        }else{
            startOffset = (fromIndex + 1) * quadSize;
            moveLength = (newIndex - fromIndex) * quadSize;
            locQuadsReader.set(locQuadsReader.subarray(startOffset, startOffset + moveLength),startOffset - quadSize);
            locQuadsReader.set(sourceArr, newIndex * quadSize);
        }
        this._dirty = true;
    },

    /**
     * <p>Removes a quad at a given index number.<br />
     * The capacity remains the same, but the total number of quads to be drawn is reduced in 1 </p>
     * @param {Number} index
     */
    removeQuadAtIndex:function (index) {
        if(index >= this._totalQuads)
            throw "cc.TextureAtlas.removeQuadAtIndex(): Invalid index";
        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        this._totalQuads--;
        this._quads.length = this._totalQuads;
        if(index !== this._totalQuads){
            //move data
            var startOffset = (index + 1) * quadSize;
            var moveLength = (this._totalQuads - index) * quadSize;
            this._quadsReader.set(this._quadsReader.subarray(startOffset, startOffset + moveLength), startOffset - quadSize);
        }
        this._dirty = true;
    },

    removeQuadsAtIndex:function (index, amount) {
        if(index + amount > this._totalQuads)
            throw "cc.TextureAtlas.removeQuadsAtIndex(): index + amount out of bounds";
        this._totalQuads -= amount;

        if(index !== this._totalQuads){
            //move data
            var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
            var srcOffset = (index + amount) * quadSize;
            var moveLength = (this._totalQuads - index) * quadSize;
            var dstOffset = index * quadSize;
            this._quadsReader.set(this._quadsReader.subarray(srcOffset,srcOffset + moveLength),dstOffset);
        }
        this._dirty = true;
    },

    /**
     * <p>Removes all Quads. <br />
     * The TextureAtlas capacity remains untouched. No memory is freed.<br />
     * The total number of quads to be drawn will be 0</p>
     */
    removeAllQuads:function () {
        this._quads.length = 0;
        this._totalQuads = 0;
    },

    _setDirty:function(dirty){
        this._dirty = dirty;
    },

    /**
     * <p>Resize the capacity of the CCTextureAtlas.<br />
     * The new capacity can be lower or higher than the current one<br />
     * It returns YES if the resize was successful. <br />
     * If it fails to resize the capacity it will return NO with a new capacity of 0. <br />
     * no used for js</p>
     * @param {Number} newCapacity
     * @return {Boolean}
     */
    resizeCapacity:function (newCapacity) {
        if (newCapacity == this._capacity)
            return true;

        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        var oldCapacity = this._capacity;
        // update capacity and totolQuads
        this._totalQuads = Math.min(this._totalQuads, newCapacity);
        this._capacity = 0 | newCapacity;
        var i, capacity = this._capacity, locTotalQuads = this._totalQuads;

        if (this._quads == null) {
            this._quads = [];
            this._quadsArrayBuffer = new ArrayBuffer(quadSize * capacity);
            this._quadsReader = new Uint8Array(this._quadsArrayBuffer);
            for(i = 0; i< capacity; i++)
                this._quads = new cc.V3F_C4B_T2F_Quad(null, null, null, null, this._quadsArrayBuffer,i * quadSize);
        } else {
            var newQuads, newArrayBuffer, quads = this._quads;
            if (capacity > oldCapacity) {
                newQuads = [];
                newArrayBuffer = new ArrayBuffer(quadSize * capacity);
                for(i = 0; i < locTotalQuads;i++){
                     newQuads[i] = new cc.V3F_C4B_T2F_Quad(quads[i].tl,quads[i].bl,quads[i].tr,quads[i].br,
                         newArrayBuffer,i * quadSize);
                }
                for(;i<capacity; i ++)
                    newQuads[i] = new cc.V3F_C4B_T2F_Quad(null,null,null,null, newArrayBuffer,i * quadSize);

                this._quadsReader = new Uint8Array(newArrayBuffer);
                this._quads = newQuads;
                this._quadsArrayBuffer = newArrayBuffer;
            } else {
                var count = Math.max(locTotalQuads, capacity);
                newQuads = [];
                newArrayBuffer = new ArrayBuffer(quadSize * capacity);
                for(i = 0; i < count;i++){
                    newQuads[i] = new cc.V3F_C4B_T2F_Quad(quads[i].tl,quads[i].bl,quads[i].tr,quads[i].br,
                        newArrayBuffer,i * quadSize);
                }
                this._quadsReader = new Uint8Array(newArrayBuffer);
                this._quads = newQuads;
                this._quadsArrayBuffer = newArrayBuffer;
            }
        }

        if (this._indices == null) {
            this._indices = new Uint16Array(capacity * 6);
        } else {
            if (capacity > oldCapacity) {
                var tempIndices = new Uint16Array(capacity * 6);
                tempIndices.set(this._indices, 0);
                this._indices = tempIndices;
            } else {
                this._indices = this._indices.subarray(0, capacity * 6);
            }
        }

        this._setupIndices();
        this._mapBuffers();
        this._dirty = true;
        return true;
    },

    /**
     * Used internally by CCParticleBatchNode                                    <br/>
     * don't use this unless you know what you're doing
     * @param {Number} amount
     */
    increaseTotalQuadsWith:function (amount) {
        this._totalQuads += amount;
    },

    /**
     * Moves an amount of quads from oldIndex at newIndex
     * @param {Number} oldIndex
     * @param {Number} amount
     * @param {Number} newIndex
     */
    moveQuadsFromIndex: function (oldIndex, amount, newIndex) {
        if (newIndex === undefined) {
            newIndex = amount;
            amount = this._totalQuads - oldIndex;
            if((newIndex + (this._totalQuads - oldIndex)) > this._capacity)
                throw "cc.TextureAtlas.moveQuadsFromIndex(): move is out of bounds";
            if(amount === 0)
                return;
        }else{
            if((newIndex + amount) > this._totalQuads)
                throw "cc.TextureAtlas.moveQuadsFromIndex(): Invalid newIndex";
            if(oldIndex >= this._totalQuads)
                throw "cc.TextureAtlas.moveQuadsFromIndex(): Invalid oldIndex";

            if (oldIndex == newIndex)
                return;
        }

        var quadSize = cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        var srcOffset = oldIndex * quadSize;
        var srcLength = amount * quadSize;
        var locQuadsReader = this._quadsReader;
        var sourceArr = locQuadsReader.subarray(srcOffset, srcOffset + srcLength);
        var dstOffset = newIndex * quadSize;
        var moveLength, moveStart;
        if (newIndex < oldIndex) {
            moveLength = (oldIndex - newIndex) * quadSize;
            moveStart = newIndex * quadSize;
            locQuadsReader.set(locQuadsReader.subarray(moveStart, moveStart + moveLength), moveStart + srcLength)
        } else {
            moveLength = (newIndex - oldIndex) * quadSize;
            moveStart = (oldIndex + amount) * quadSize;
            locQuadsReader.set(locQuadsReader.subarray(moveStart, moveStart + moveLength), srcOffset);
        }
        locQuadsReader.set(sourceArr, dstOffset);
        this._dirty = true;
    },

    /**
     * Ensures that after a realloc quads are still empty                                <br/>
     * Used internally by CCParticleBatchNode
     * @param {Number} index
     * @param {Number} amount
     */
    fillWithEmptyQuadsFromIndex:function (index, amount) {
        var count = amount * cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT;
        var clearReader = new Uint8Array(this._quadsArrayBuffer, index * cc.V3F_C4B_T2F_Quad.BYTES_PER_ELEMENT, count);
        for (var i = 0; i < count; i++)
            clearReader[i] = 0;
    },

    // TextureAtlas - Drawing

    /**
     * <p>Draws n quads from an index (offset). <br />
     * n + start can't be greater than the capacity of the atlas</p>
     * @param {Number} n
     * @param {Number} start
     */
    drawNumberOfQuads:function (n, start) {
        start = start || 0;
        if (0 === n || !this._texture || !this._texture.isLoaded())
            return;

        var gl = cc.renderContext;
        cc.glBindTexture2D(this._texture);

        //
        // Using VBO without VAO
        //
        //vertices
        //gl.bindBuffer(gl.ARRAY_BUFFER, this._buffersVBO[0]);
        // XXX: update is done in draw... perhaps it should be done in a timer
        cc.glEnableVertexAttribs(cc.VERTEX_ATTRIB_FLAG_POS_COLOR_TEX);

        gl.bindBuffer(gl.ARRAY_BUFFER, this._quadsWebBuffer);
        if (this._dirty)
            gl.bufferData(gl.ARRAY_BUFFER, this._quadsArrayBuffer, gl.DYNAMIC_DRAW);

        gl.vertexAttribPointer(cc.VERTEX_ATTRIB_POSITION, 3, gl.FLOAT, false, 24, 0);               // vertices
        gl.vertexAttribPointer(cc.VERTEX_ATTRIB_COLOR, 4, gl.UNSIGNED_BYTE, true, 24, 12);          // colors
        gl.vertexAttribPointer(cc.VERTEX_ATTRIB_TEX_COORDS, 2, gl.FLOAT, false, 24, 16);            // tex coords

        if (this._dirty)
            this._dirty = false;

        gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, this._buffersVBO[1]);

        if (cc.TEXTURE_ATLAS_USE_TRIANGLE_STRIP)
            gl.drawElements(gl.TRIANGLE_STRIP, n * 6, gl.UNSIGNED_SHORT, start * 6 * this._indices.BYTES_PER_ELEMENT);
        else
            gl.drawElements(gl.TRIANGLES, n * 6, gl.UNSIGNED_SHORT, start * 6 * this._indices.BYTES_PER_ELEMENT);

        cc.g_NumberOfDraws++;
        //cc.CHECK_GL_ERROR_DEBUG();
    },

    /**
     * Draws all the Atlas's Quads
     */
    drawQuads:function () {
        this.drawNumberOfQuads(this._totalQuads, 0);
    },

    _releaseBuffer: function () {
        var gl = cc.renderContext;
        if (this._buffersVBO) {
            if (this._buffersVBO[0])
                gl.deleteBuffer(this._buffersVBO[0]);
            if (this._buffersVBO[1])
                gl.deleteBuffer(this._buffersVBO[1])
        }
        if (this._quadsWebBuffer)
            gl.deleteBuffer(this._quadsWebBuffer);
    }
});

/**
 * <p>Creates a TextureAtlas with an filename and with an initial capacity for Quads. <br />
 * The TextureAtlas capacity can be increased in runtime. </p>
 * @param {String} file
 * @param {Number} capacity
 * @return {cc.TextureAtlas|Null}
 * @example
 * //example
 * var textureAtlas = cc.TextureAtlas.create("hello.png", 3);
 */
cc.TextureAtlas.create = function (file, capacity) {
    var textureAtlas = new cc.TextureAtlas();
    if (textureAtlas && textureAtlas.initWithFile(file, capacity))
        return textureAtlas;
    return null;
};

/**
 * <p>Creates a TextureAtlas with a previously initialized Texture2D object, and with an initial capacity for n Quads.
 * The TextureAtlas capacity can be increased in runtime.</p>
 * @param {Image|cc.Texture2D} texture
 * @param {Number} capacity
 * @return {cc.TextureAtlas}
 * @example
 * //example
 * var texture = cc.TextureCache.getInstance().addImage("hello.png");
 * var textureAtlas = cc.TextureAtlas.createWithTexture(texture, 3);
 */
cc.TextureAtlas.createWithTexture = function (texture, capacity) {
    var textureAtlas = new cc.TextureAtlas();
    if (textureAtlas && textureAtlas.initWithTexture(texture, capacity))
        return textureAtlas;
    return null;
};