Babylon.js/src/Cameras/Inputs/babylon.arcRotateCameraGamepadInput.ts

module BABYLON {
    /**
     * Manage the gamepad inputs to control an arc rotate camera.
     * @see http://doc.babylonjs.com/how_to/customizing_camera_inputs
     */
    export class ArcRotateCameraGamepadInput implements ICameraInput<ArcRotateCamera> {
        /**
         * Defines the camera the input is attached to.
         */
        public camera: ArcRotateCamera;

        /**
         * Defines the gamepad the input is gathering event from.
         */
        public gamepad: Nullable<Gamepad>;

        /**
         * Defines the gamepad rotation sensiblity.
         * This is the threshold from when rotation starts to be accounted for to prevent jittering.
         */
        @serialize()
        public gamepadRotationSensibility = 80;

        /**
         * Defines the gamepad move sensiblity.
         * This is the threshold from when moving starts to be accounted for for to prevent jittering.
         */
        @serialize()
        public gamepadMoveSensibility = 40;

        private _onGamepadConnectedObserver : Nullable<Observer<Gamepad>>;
        private _onGamepadDisconnectedObserver : Nullable<Observer<Gamepad>>;

        /**
         * Attach the input controls to a specific dom element to get the input from.
         * @param element Defines the element the controls should be listened from
         * @param noPreventDefault Defines whether event caught by the controls should call preventdefault() (https://developer.mozilla.org/en-US/docs/Web/API/Event/preventDefault)
         */
        public attachControl(element: HTMLElement, noPreventDefault?: boolean): void {
            let manager = this.camera.getScene().gamepadManager;
            this._onGamepadConnectedObserver = manager.onGamepadConnectedObservable.add((gamepad) => {
                if (gamepad.type !== Gamepad.POSE_ENABLED) {
                    // prioritize XBOX gamepads.
                    if (!this.gamepad || gamepad.type === Gamepad.XBOX) {
                        this.gamepad = gamepad;
                    }
                }
            });

            this._onGamepadDisconnectedObserver = manager.onGamepadDisconnectedObservable.add((gamepad)=> {
                if (this.gamepad === gamepad) {
                    this.gamepad = null;
                }
            });
            
            this.gamepad = manager.getGamepadByType(Gamepad.XBOX);
        }

        /**
         * Detach the current controls from the specified dom element.
         * @param element Defines the element to stop listening the inputs from
         */
        public detachControl(element: Nullable<HTMLElement>): void {
            this.camera.getScene().gamepadManager.onGamepadConnectedObservable.remove(this._onGamepadConnectedObserver);            
            this.camera.getScene().gamepadManager.onGamepadDisconnectedObservable.remove(this._onGamepadDisconnectedObserver);
            this.gamepad = null;
        }

        /**
         * Update the current camera state depending on the inputs that have been used this frame.
         * This is a dynamically created lambda to avoid the performance penalty of looping for inputs in the render loop.
         */
        public checkInputs(): void {
            if (this.gamepad) {
                var camera = this.camera;
                var RSValues = this.gamepad.rightStick;

                if (RSValues) {
                    if (RSValues.x != 0) {
                        var normalizedRX = RSValues.x / this.gamepadRotationSensibility;
                        if (normalizedRX != 0 && Math.abs(normalizedRX) > 0.005) {
                            camera.inertialAlphaOffset += normalizedRX;
                        }
                    }

                    if (RSValues.y != 0) {
                        var normalizedRY = RSValues.y / this.gamepadRotationSensibility;
                        if (normalizedRY != 0 && Math.abs(normalizedRY) > 0.005) {
                            camera.inertialBetaOffset += normalizedRY;
                        }
                    }
                }

                var LSValues = this.gamepad.leftStick;
                if (LSValues && LSValues.y != 0) {
                    var normalizedLY = LSValues.y / this.gamepadMoveSensibility;
                    if (normalizedLY != 0 && Math.abs(normalizedLY) > 0.005) {
                        this.camera.inertialRadiusOffset -= normalizedLY;
                    }
                }

            }
        }

        /**
         * Gets the class name of the current intput.
         * @returns the class name
         */
        public getClassName(): string {
            return "ArcRotateCameraGamepadInput";
        }

        /**
         * Get the friendly name associated with the input class.
         * @returns the input friendly name
         */
        public getSimpleName(): string {
            return "gamepad";
        }        
    }

    (<any>CameraInputTypes)["ArcRotateCameraGamepadInput"] = ArcRotateCameraGamepadInput;
}