Phaser Source: src/gameobjects/RenderTexture.js

# Source: src/gameobjects/RenderTexture.js

    /**
    * @author       Richard Davey <rich@photonstorm.com>
    * @copyright    2016 Photon Storm Ltd.
    * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
    */

    /**
    * A RenderTexture is a special texture that allows any displayObject to be rendered to it. It allows you to take many complex objects and
    * render them down into a single quad (on WebGL) which can then be used to texture other display objects with. A way of generating textures at run-time.
    *
    * @class Phaser.RenderTexture
    * @constructor
    * @extends PIXI.RenderTexture
    * @param {Phaser.Game} game - Current game instance.
    * @param {number} [width=100] - The width of the render texture.
    * @param {number} [height=100] - The height of the render texture.
    * @param {string} [key=''] - The key of the RenderTexture in the Cache, if stored there.
    * @param {number} [scaleMode=Phaser.scaleModes.DEFAULT] - One of the Phaser.scaleModes consts.
    * @param {number} [resolution=1] - The resolution of the texture being generated.
    */
    Phaser.RenderTexture = function (game, width, height, key, scaleMode, resolution) {

        if (key === undefined) { key = ''; }
        if (scaleMode === undefined) { scaleMode = Phaser.scaleModes.DEFAULT; }
        if (resolution === undefined) { resolution = 1; }

        /**
        * @property {Phaser.Game} game - A reference to the currently running game.
        */
        this.game = game;

        /**
        * @property {string} key - The key of the RenderTexture in the Cache, if stored there.
        */
        this.key = key;

        /**
        * @property {number} type - Base Phaser object type.
        */
        this.type = Phaser.RENDERTEXTURE;

        /**
        * @property {PIXI.Matrix} _tempMatrix - The matrix that is applied when display objects are rendered to this RenderTexture.
        * @private
        */
        this._tempMatrix = new PIXI.Matrix();

        PIXI.RenderTexture.call(this, width, height, this.game.renderer, scaleMode, resolution);

        this.render = Phaser.RenderTexture.prototype.render;

    };

    Phaser.RenderTexture.prototype = Object.create(PIXI.RenderTexture.prototype);
    Phaser.RenderTexture.prototype.constructor = Phaser.RenderTexture;

    /**
    * This function will draw the display object to the RenderTexture at the given coordinates.
    *
    * When the display object is drawn it takes into account scale and rotation.
    *
    * If you don't want those then use RenderTexture.renderRawXY instead.
    *
    * @method Phaser.RenderTexture.prototype.renderXY
    * @param {Phaser.Sprite|Phaser.Image|Phaser.Text|Phaser.BitmapText|Phaser.Group} displayObject - The display object to render to this texture.
    * @param {number} x - The x position to render the object at.
    * @param {number} y - The y position to render the object at.
    * @param {boolean} [clear=false] - If true the texture will be cleared before the display object is drawn.
    */
    Phaser.RenderTexture.prototype.renderXY = function (displayObject, x, y, clear) {

        displayObject.updateTransform();

        this._tempMatrix.copyFrom(displayObject.worldTransform);
        this._tempMatrix.tx = x;
        this._tempMatrix.ty = y;

        if (this.renderer.type === PIXI.WEBGL_RENDERER)
        {
            this.renderWebGL(displayObject, this._tempMatrix, clear);
        }
        else
        {
            this.renderCanvas(displayObject, this._tempMatrix, clear);
        }

    };

    /**
    * This function will draw the display object to the RenderTexture at the given coordinates.
    *
    * When the display object is drawn it doesn't take into account scale, rotation or translation.
    *
    * If you need those then use RenderTexture.renderXY instead.
    *
    * @method Phaser.RenderTexture.prototype.renderRawXY
    * @param {Phaser.Sprite|Phaser.Image|Phaser.Text|Phaser.BitmapText|Phaser.Group} displayObject - The display object to render to this texture.
    * @param {number} x - The x position to render the object at.
    * @param {number} y - The y position to render the object at.
    * @param {boolean} [clear=false] - If true the texture will be cleared before the display object is drawn.
    */
    Phaser.RenderTexture.prototype.renderRawXY = function (displayObject, x, y, clear) {

        this._tempMatrix.identity().translate(x, y);

        if (this.renderer.type === PIXI.WEBGL_RENDERER)
        {
            this.renderWebGL(displayObject, this._tempMatrix, clear);
        }
        else
        {
            this.renderCanvas(displayObject, this._tempMatrix, clear);
        }

    };

    /**
    * This function will draw the display object to the RenderTexture.
    *
    * In versions of Phaser prior to 2.4.0 the second parameter was a Phaser.Point object.
    * This is now a Matrix allowing you much more control over how the Display Object is rendered.
    * If you need to replicate the earlier behavior please use Phaser.RenderTexture.renderXY instead.
    *
    * If you wish for the displayObject to be rendered taking its current scale, rotation and translation into account then either
    * pass `null`, leave it undefined or pass `displayObject.worldTransform` as the matrix value.
    *
    * @method Phaser.RenderTexture.prototype.render
    * @param {Phaser.Sprite|Phaser.Image|Phaser.Text|Phaser.BitmapText|Phaser.Group} displayObject - The display object to render to this texture.
    * @param {Phaser.Matrix} [matrix] - Optional matrix to apply to the display object before rendering. If null or undefined it will use the worldTransform matrix of the given display object.
    * @param {boolean} [clear=false] - If true the texture will be cleared before the display object is drawn.
    */
    Phaser.RenderTexture.prototype.render = function (displayObject, matrix, clear) {

        if (matrix === undefined || matrix === null)
        {
            this._tempMatrix.copyFrom(displayObject.worldTransform);
        }
        else
        {
            this._tempMatrix.copyFrom(matrix);
        }

        if (this.renderer.type === PIXI.WEBGL_RENDERER)
        {
            this.renderWebGL(displayObject, this._tempMatrix, clear);
        }
        else
        {
            this.renderCanvas(displayObject, this._tempMatrix, clear);
        }

    };