Babylon.js/src/Gamepad/babylon.gamepadSceneComponent.ts

module BABYLON {
    export interface Scene {
        /** @hidden */
        _gamepadManager: Nullable<GamepadManager>;

        /**
         * Gets the gamepad manager associated with the scene
         * @see http://doc.babylonjs.com/how_to/how_to_use_gamepads
         */
        gamepadManager: GamepadManager;
    }

    Object.defineProperty(Scene.prototype, "gamepadManager", {
        get: function(this: Scene) {
            if (!this._gamepadManager) {
                this._gamepadManager = new GamepadManager(this);
                let component = this._getComponent(SceneComponentConstants.NAME_GAMEPAD) as GamepadSystemSceneComponent;
                if (!component) {
                    component = new GamepadSystemSceneComponent(this);
                    this._addComponent(component);
                }
            }

            return this._gamepadManager;
        },
        enumerable: true,
        configurable: true
    });

    /**
     * Interface representing a free camera inputs manager
     */
    export interface FreeCameraInputsManager {
        /**
         * Adds gamepad input support to the FreeCameraInputsManager.
         * @returns the FreeCameraInputsManager
         */
        addGamepad(): FreeCameraInputsManager;
    }

    /**
     * Adds a gamepad to the free camera inputs manager
     */
    FreeCameraInputsManager.prototype.addGamepad = function(): FreeCameraInputsManager {
        this.add(new FreeCameraGamepadInput());
        return this;
    };

    /**
     * Interface representing an arc rotate camera inputs manager
     */
    export interface ArcRotateCameraInputsManager {
        /**
         * Adds gamepad input support to the ArcRotateCamera InputManager.
         * @returns the camera inputs manager
         */
        addGamepad(): ArcRotateCameraInputsManager;
    }

    /**
     * Adds a gamepad to the arc rotate camera inputs manager
     */
    ArcRotateCameraInputsManager.prototype.addGamepad = function(): ArcRotateCameraInputsManager {
        this.add(new ArcRotateCameraGamepadInput());
        return this;
    };

   /**
     * Defines the gamepad scene component responsible to manage gamepads in a given scene
     */
    export class GamepadSystemSceneComponent implements ISceneComponent {
        /**
         * The component name helpfull to identify the component in the list of scene components.
         */
        public readonly name = SceneComponentConstants.NAME_GAMEPAD;

        /**
         * The scene the component belongs to.
         */
        public scene: Scene;

        /**
         * Creates a new instance of the component for the given scene
         * @param scene Defines the scene to register the component in
         */
        constructor(scene: Scene) {
            this.scene = scene;
        }

        /**
         * Registers the component in a given scene
         */
        public register(): void {
            this.scene._beforeCameraUpdateStage.registerStep(SceneComponentConstants.STEP_BEFORECAMERAUPDATE_GAMEPAD, this, this._beforeCameraUpdate);
        }

        /**
         * Rebuilds the elements related to this component in case of
         * context lost for instance.
         */
        public rebuild(): void {
            // Nothing to do for gamepads
        }

        /**
         * Disposes the component and the associated ressources
         */
        public dispose(): void {
            let gamepadManager = this.scene._gamepadManager;
            if (gamepadManager) {
                gamepadManager.dispose();
                this.scene._gamepadManager = null;
            }
        }

        private _beforeCameraUpdate(): void {
            let gamepadManager = this.scene._gamepadManager;

            if (gamepadManager && gamepadManager._isMonitoring) {
                gamepadManager._checkGamepadsStatus();
            }
        }
    }
}