# Source: gameobjects/Image.js

    /**
    * @author       Richard Davey <rich@photonstorm.com>
    * @copyright    2014 Photon Storm Ltd.
    * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
    */

    /**
    * @class Phaser.Image
    *
    * @classdesc Create a new `Image` object. An Image is a light-weight object you can use to display anything that doesn't need physics or animation.
    * It can still rotate, scale, crop and receive input events. This makes it perfect for logos, backgrounds, simple buttons and other non-Sprite graphics.
    *
    * @constructor
    * @param {Phaser.Game} game - A reference to the currently running game.
    * @param {number} x - The x coordinate of the Image. The coordinate is relative to any parent container this Image may be in.
    * @param {number} y - The y coordinate of the Image. The coordinate is relative to any parent container this Image may be in.
    * @param {string|Phaser.RenderTexture|Phaser.BitmapData|PIXI.Texture} key - The texture used by the Image during rendering. It can be a string which is a reference to the Cache entry, or an instance of a RenderTexture, BitmapData or PIXI.Texture.
    * @param {string|number} frame - If this Image is using part of a sprite sheet or texture atlas you can specify the exact frame to use by giving a string or numeric index.
    */
    Phaser.Image = function (game, x, y, key, frame) {

        x = x || 0;
        y = y || 0;
        key = key || null;
        frame = frame || null;

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

        /**
        * @property {boolean} exists - If exists = false then the Image isn't updated by the core game loop.
        * @default
        */
        this.exists = true;

        /**
        * @property {string} name - The user defined name given to this Image.
        * @default
        */
        this.name = '';

        /**
        * @property {number} type - The const type of this object.
        * @readonly
        */
        this.type = Phaser.IMAGE;

        /**
        * @property {number} z - The z-depth value of this object within its Group (remember the World is a Group as well). No two objects in a Group can have the same z value.
        */
        this.z = 0;

        /**
        * @property {Phaser.Events} events - The Events you can subscribe to that are dispatched when certain things happen on this Image or its components.
        */
        this.events = new Phaser.Events(this);

        /**
        *  @property {string|Phaser.RenderTexture|Phaser.BitmapData|PIXI.Texture} key - This is the image or texture used by the Image during rendering. It can be a string which is a reference to the Cache entry, or an instance of a RenderTexture, BitmapData or PIXI.Texture.
        */
        this.key = key;

        /**
        * @property {number} _frame - Internal cache var.
        * @private
        */
        this._frame = 0;

        /**
        * @property {string} _frameName - Internal cache var.
        * @private
        */
        this._frameName = '';

        PIXI.Sprite.call(this, PIXI.TextureCache['__default']);

        this.loadTexture(key, frame);

        this.position.set(x, y);

        /**
        * @property {Phaser.Point} world - The world coordinates of this Image. This differs from the x/y coordinates which are relative to the Images container.
        */
        this.world = new Phaser.Point(x, y);

        /**
        * Should this Image be automatically culled if out of range of the camera?
        * A culled sprite has its renderable property set to 'false'.
        * Be advised this is quite an expensive operation, as it has to calculate the bounds of the object every frame, so only enable it if you really need it.
        *
        * @property {boolean} autoCull - A flag indicating if the Image should be automatically camera culled or not.
        * @default
        */
        this.autoCull = false;

        /**
        * @property {Phaser.InputHandler|null} input - The Input Handler for this object. Needs to be enabled with image.inputEnabled = true before you can use it.
        */
        this.input = null;

        /**
        * @property {Phaser.Point} cameraOffset - If this object is fixedToCamera then this stores the x/y offset that its drawn at, from the top-left of the camera view.
        */
        this.cameraOffset = new Phaser.Point();

        /**
        * A small internal cache:
        * 0 = previous position.x
        * 1 = previous position.y
        * 2 = previous rotation
        * 3 = renderID
        * 4 = fresh? (0 = no, 1 = yes)
        * 5 = outOfBoundsFired (0 = no, 1 = yes)
        * 6 = exists (0 = no, 1 = yes)
        * 7 = fixed to camera (0 = no, 1 = yes)
        * 8 = destroy phase? (0 = no, 1 = yes)
        * @property {Array} _cache
        * @private
        */
        this._cache = [ 0, 0, 0, 0, 1, 0, 1, 0, 0 ];

    };

    Phaser.Image.prototype = Object.create(PIXI.Sprite.prototype);
    Phaser.Image.prototype.constructor = Phaser.Image;

    /**
    * Automatically called by World.preUpdate.
    *
    * @method Phaser.Image#preUpdate
    * @memberof Phaser.Image
    */
    Phaser.Image.prototype.preUpdate = function() {

        this._cache[0] = this.world.x;
        this._cache[1] = this.world.y;
        this._cache[2] = this.rotation;

        if (!this.exists || !this.parent.exists)
        {
            this._cache[3] = -1;
            return false;
        }

        if (this.autoCull)
        {
            //  Won't get rendered but will still get its transform updated
            this.renderable = this.game.world.camera.screenView.intersects(this.getBounds());
        }

        this.world.setTo(this.game.camera.x + this.worldTransform[2], this.game.camera.y + this.worldTransform[5]);

        if (this.visible)
        {
            this._cache[3] = this.game.stage.currentRenderOrderID++;
        }

        //  Update any Children
        for (var i = 0, len = this.children.length; i < len; i++)
        {
            this.children[i].preUpdate();
        }

        return true;

    };

    /**
    * Override and use this function in your own custom objects to handle any update requirements you may have.
    *
    * @method Phaser.Image#update
    * @memberof Phaser.Image
    */
    Phaser.Image.prototype.update = function() {

    };

    /**
    * Internal function called by the World postUpdate cycle.
    *
    * @method Phaser.Image#postUpdate
    * @memberof Phaser.Image
    */
    Phaser.Image.prototype.postUpdate = function() {

        if (this.key instanceof Phaser.BitmapData)
        {
            this.key.render();
        }

        //  Fixed to Camera?
        if (this._cache[7] === 1)
        {
            this.position.x = (this.game.camera.view.x + this.cameraOffset.x) / this.game.camera.scale.x;
            this.position.y = (this.game.camera.view.y + this.cameraOffset.y) / this.game.camera.scale.y;
        }

        //  Update any Children
        for (var i = 0, len = this.children.length; i < len; i++)
        {
            this.children[i].postUpdate();
        }

    };

    /**
    * Changes the Texture the Image is using entirely. The old texture is removed and the new one is referenced or fetched from the Cache.
    * This causes a WebGL texture update, so use sparingly or in low-intensity portions of your game.
    *
    * @method Phaser.Image#loadTexture
    * @memberof Phaser.Image
    * @param {string|Phaser.RenderTexture|Phaser.BitmapData|PIXI.Texture} key - This is the image or texture used by the Image during rendering. It can be a string which is a reference to the Cache entry, or an instance of a RenderTexture, BitmapData or PIXI.Texture.
    * @param {string|number} frame - If this Image is using part of a sprite sheet or texture atlas you can specify the exact frame to use by giving a string or numeric index.
    */
    Phaser.Image.prototype.loadTexture = function (key, frame) {

        frame = frame || 0;

        if (key instanceof Phaser.RenderTexture)
        {
            this.key = key.key;
            this.setTexture(key);
            return;
        }
        else if (key instanceof Phaser.BitmapData)
        {
            this.key = key;
            this.setTexture(key.texture);
            return;
        }
        else if (key instanceof PIXI.Texture)
        {
            this.key = key;
            this.setTexture(key);
            return;
        }
        else
        {
            if (key === null || typeof key === 'undefined')
            {
                this.key = '__default';
                this.setTexture(PIXI.TextureCache[this.key]);
                return;
            }
            else if (typeof key === 'string' && !this.game.cache.checkImageKey(key))
            {
                this.key = '__missing';
                this.setTexture(PIXI.TextureCache[this.key]);
                return;
            }

            if (this.game.cache.isSpriteSheet(key))
            {
                this.key = key;

                var frameData = this.game.cache.getFrameData(key);

                if (typeof frame === 'string')
                {
                    this._frame = 0;
                    this._frameName = frame;
                    this.setTexture(PIXI.TextureCache[frameData.getFrameByName(frame).uuid]);
                    return;
                }
                else
                {
                    this._frame = frame;
                    this._frameName = '';
                    this.setTexture(PIXI.TextureCache[frameData.getFrame(frame).uuid]);
                    return;
                }
            }
            else
            {
                this.key = key;
                this.setTexture(PIXI.TextureCache[key]);
                return;
            }
        }

    };

    /**
    * Crop allows you to crop the texture used to display this Image.
    * Cropping takes place from the top-left of the Image and can be modified in real-time by providing an updated rectangle object.
    * The rectangle object given to this method can be either a Phaser.Rectangle or any object so long as it has public x, y, width and height properties.
    * Please note that the rectangle object given is not duplicated by this method, but rather the Image uses a reference to the rectangle.
    * Keep this in mind if assigning a rectangle in a for-loop, or when cleaning up for garbage collection.
    *
    * @method Phaser.Image#crop
    * @memberof Phaser.Image
    * @param {Phaser.Rectangle|object} rect - The Rectangle to crop the Image to. Pass null or no parameters to clear a previously set crop rectangle.
    */
    Phaser.Image.prototype.crop = function(rect) {

        if (typeof rect === 'undefined' || rect === null)
        {
            //  Clear any crop that may be set
            if (this.texture.hasOwnProperty('sourceWidth'))
            {
                this.texture.setFrame(new Phaser.Rectangle(0, 0, this.texture.sourceWidth, this.texture.sourceHeight));
            }
        }
        else
        {
            //  Do we need to clone the PIXI.Texture object?
            if (this.texture instanceof PIXI.Texture)
            {
                //  Yup, let's rock it ...
                var local = {};

                Phaser.Utils.extend(true, local, this.texture);

                local.sourceWidth = local.width;
                local.sourceHeight = local.height;
                local.frame = rect;
                local.width = rect.width;
                local.height = rect.height;

                this.texture = local;

                this.texture.updateFrame = true;
                PIXI.Texture.frameUpdates.push(this.texture);
            }
            else
            {
                this.texture.setFrame(rect);
            }
        }

    };

    /**
    * Brings a 'dead' Image back to life, optionally giving it the health value specified.
    * A resurrected Image has its alive, exists and visible properties all set to true.
    * It will dispatch the onRevived event, you can listen to Image.events.onRevived for the signal.
    *
    * @method Phaser.Image#revive
    * @memberof Phaser.Image
    * @return {Phaser.Image} This instance.
    */
    Phaser.Image.prototype.revive = function() {

        this.alive = true;
        this.exists = true;
        this.visible = true;

        if (this.events)
        {
            this.events.onRevived.dispatch(this);
        }

        return this;

    };

    /**
    * Kills a Image. A killed Image has its alive, exists and visible properties all set to false.
    * It will dispatch the onKilled event, you can listen to Image.events.onKilled for the signal.
    * Note that killing a Image is a way for you to quickly recycle it in a Image pool, it doesn't free it up from memory.
    * If you don't need this Image any more you should call Image.destroy instead.
    *
    * @method Phaser.Image#kill
    * @memberof Phaser.Image
    * @return {Phaser.Image} This instance.
    */
    Phaser.Image.prototype.kill = function() {

        this.alive = false;
        this.exists = false;
        this.visible = false;

        if (this.events)
        {
            this.events.onKilled.dispatch(this);
        }

        return this;

    };

    /**
    * Destroys the Image. This removes it from its parent group, destroys the input, event and animation handlers if present
    * and nulls its reference to game, freeing it up for garbage collection.
    *
    * @method Phaser.Image#destroy
    * @memberof Phaser.Image
    * @param {boolean} [destroyChildren=true] - Should every child of this object have its destroy method called?
    */
    Phaser.Image.prototype.destroy = function(destroyChildren) {

        if (this.game === null || this.destroyPhase) { return; }

        if (typeof destroyChildren === 'undefined') { destroyChildren = true; }

        this._cache[8] = 1;

        if (this.parent)
        {
            if (this.parent instanceof Phaser.Group)
            {
                this.parent.remove(this);
            }
            else
            {
                this.parent.removeChild(this);
            }
        }

        if (this.events)
        {
            this.events.destroy();
        }

        if (this.input)
        {
            this.input.destroy();
        }

        var i = this.children.length;

        if (destroyChildren)
        {
            while (i--)
            {
                this.children[i].destroy(destroyChildren);
            }
        }
        else
        {
            while (i--)
            {
                this.removeChild(this.children[i]);
            }
        }

        this.alive = false;
        this.exists = false;
        this.visible = false;

        this.filters = null;
        this.mask = null;
        this.game = null;

        this._cache[8] = 0;

    };

    /**
    * Resets the Image. This places the Image at the given x/y world coordinates and then sets alive, exists, visible and renderable all to true.
    *
    * @method Phaser.Image#reset
    * @memberof Phaser.Image
    * @param {number} x - The x coordinate (in world space) to position the Image at.
    * @param {number} y - The y coordinate (in world space) to position the Image at.
    * @return {Phaser.Image} This instance.
    */
    Phaser.Image.prototype.reset = function(x, y) {

        this.world.setTo(x, y);
        this.position.x = x;
        this.position.y = y;
        this.alive = true;
        this.exists = true;
        this.visible = true;
        this.renderable = true;

        return this;

    };

    /**
    * Brings the Image to the top of the display list it is a child of. Images that are members of a Phaser.Group are only
    * bought to the top of that Group, not the entire display list.
    *
    * @method Phaser.Image#bringToTop
    * @memberof Phaser.Image
    * @return {Phaser.Image} This instance.
    */
    Phaser.Image.prototype.bringToTop = function() {

        if (this.parent)
        {
            this.parent.bringToTop(this);
        }

        return this;

    };

    /**
    * Indicates the rotation of the Image, in degrees, from its original orientation. Values from 0 to 180 represent clockwise rotation; values from 0 to -180 represent counterclockwise rotation.
    * Values outside this range are added to or subtracted from 360 to obtain a value within the range. For example, the statement player.angle = 450 is the same as player.angle = 90.
    * If you wish to work in radians instead of degrees use the property Image.rotation instead. Working in radians is also a little faster as it doesn't have to convert the angle.
    *
    * @name Phaser.Image#angle
    * @property {number} angle - The angle of this Image in degrees.
    */
    Object.defineProperty(Phaser.Image.prototype, "angle", {

        get: function() {

            return Phaser.Math.wrapAngle(Phaser.Math.radToDeg(this.rotation));

        },

        set: function(value) {

            this.rotation = Phaser.Math.degToRad(Phaser.Math.wrapAngle(value));

        }

    });

    /**
    * Returns the delta x value. The difference between world.x now and in the previous step.
    *
    * @name Phaser.Image#deltaX
    * @property {number} deltaX - The delta value. Positive if the motion was to the right, negative if to the left.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "deltaX", {

        get: function() {

            return this.world.x - this._cache[0];

        }

    });

    /**
    * Returns the delta y value. The difference between world.y now and in the previous step.
    *
    * @name Phaser.Image#deltaY
    * @property {number} deltaY - The delta value. Positive if the motion was downwards, negative if upwards.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "deltaY", {

        get: function() {

            return this.world.y - this._cache[1];

        }

    });

    /**
    * Returns the delta z value. The difference between rotation now and in the previous step.
    *
    * @name Phaser.Image#deltaZ
    * @property {number} deltaZ - The delta value.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "deltaZ", {

        get: function() {

            return this.rotation - this._cache[2];

        }

    });

    /**
    * Checks if the Image bounds are within the game world, otherwise false if fully outside of it.
    *
    * @name Phaser.Image#inWorld
    * @property {boolean} inWorld - True if the Image bounds is within the game world, even if only partially. Otherwise false if fully outside of it.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "inWorld", {

        get: function() {

            return this.game.world.bounds.intersects(this.getBounds());

        }

    });

    /**
    * Checks if the Image bounds are within the game camera, otherwise false if fully outside of it.
    *
    * @name Phaser.Image#inCamera
    * @property {boolean} inCamera - True if the Image bounds is within the game camera, even if only partially. Otherwise false if fully outside of it.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "inCamera", {

        get: function() {

            return this.game.world.camera.screenView.intersects(this.getBounds());

        }

    });

    /**
    * @name Phaser.Image#frame
    * @property {number} frame - Gets or sets the current frame index and updates the Texture for display.
    */
    Object.defineProperty(Phaser.Image.prototype, "frame", {

        get: function() {

            return this._frame;

        },

        set: function(value) {

            if (value !== this.frame && this.game.cache.isSpriteSheet(this.key))
            {
                var frameData = this.game.cache.getFrameData(this.key);

                if (frameData && value < frameData.total && frameData.getFrame(value))
                {
                    this.setTexture(PIXI.TextureCache[frameData.getFrame(value).uuid]);
                    this._frame = value;
                }
            }

        }

    });

    /**
    * @name Phaser.Image#frameName
    * @property {string} frameName - Gets or sets the current frame by name and updates the Texture for display.
    */
    Object.defineProperty(Phaser.Image.prototype, "frameName", {

        get: function() {

            return this._frameName;

        },

        set: function(value) {

            if (value !== this.frameName && this.game.cache.isSpriteSheet(this.key))
            {
                var frameData = this.game.cache.getFrameData(this.key);

                if (frameData && frameData.getFrameByName(value))
                {
                    this.setTexture(PIXI.TextureCache[frameData.getFrameByName(value).uuid]);
                    this._frameName = value;
                }
            }

        }

    });

    /**
    * @name Phaser.Image#renderOrderID
    * @property {number} renderOrderID - The render order ID, reset every frame.
    * @readonly
    */
    Object.defineProperty(Phaser.Image.prototype, "renderOrderID", {

        get: function() {

            return this._cache[3];

        }

    });

    /**
    * By default an Image won't process any input events at all. By setting inputEnabled to true the Phaser.InputHandler is
    * activated for this object and it will then start to process click/touch events and more.
    *
    * @name Phaser.Image#inputEnabled
    * @property {boolean} inputEnabled - Set to true to allow this object to receive input events.
    */
    Object.defineProperty(Phaser.Image.prototype, "inputEnabled", {

        get: function () {

            return (this.input && this.input.enabled);

        },

        set: function (value) {

            if (value)
            {
                if (this.input === null)
                {
                    this.input = new Phaser.InputHandler(this);
                    this.input.start();
                }
                else if (this.input && !this.input.enabled)
                {
                    this.input.start();
                }
            }
            else
            {
                if (this.input && this.input.enabled)
                {
                    this.input.stop();
                }
            }
        }

    });

    /**
    * An Image that is fixed to the camera uses its x/y coordinates as offsets from the top left of the camera. These are stored in Image.cameraOffset.
    * Note that the cameraOffset values are in addition to any parent in the display list.
    * So if this Image was in a Group that has x: 200, then this will be added to the cameraOffset.x
    *
    * @name Phaser.Image#fixedToCamera
    * @property {boolean} fixedToCamera - Set to true to fix this Image to the Camera at its current world coordinates.
    */
    Object.defineProperty(Phaser.Image.prototype, "fixedToCamera", {

        get: function () {

            return !!this._cache[7];

        },

        set: function (value) {

            if (value)
            {
                this._cache[7] = 1;
                this.cameraOffset.set(this.x, this.y);
            }
            else
            {
                this._cache[7] = 0;
            }
        }

    });

    /**
    * Enable or disable texture smoothing for this Image. Only works for bitmap/image textures. Smoothing is enabled by default.
    *
    * @name Phaser.Image#smoothed
    * @property {boolean} smoothed - Set to true to smooth the texture of this Image, or false to disable smoothing (great for pixel art)
    */
    Object.defineProperty(Phaser.Image.prototype, "smoothed", {

        get: function () {

            return !this.texture.baseTexture.scaleMode;

        },

        set: function (value) {

            if (value)
            {
                if (this.texture)
                {
                    this.texture.baseTexture.scaleMode = 0;
                }
            }
            else
            {
                if (this.texture)
                {
                    this.texture.baseTexture.scaleMode = 1;
                }
            }
        }

    });

    /**
    * @name Phaser.Image#destroyPhase
    * @property {boolean} destroyPhase - True if this object is currently being destroyed.
    */
    Object.defineProperty(Phaser.Image.prototype, "destroyPhase", {

        get: function () {

            return !!this._cache[8];

        }

    });