Source: inputmanager.js

/*
 * GDevelop JS Platform
 * Copyright 2013-2016 Florian Rival ([email protected]). All rights reserved.
 * This project is released under the MIT License.
 */

/**
 * Store input made on a canvas: mouse position, key pressed
 * and touches states.
 *
 * See **bindStandardEvents** method for connecting the input
 * manager to a canvas and **onFrameEnded** for signaling the
 * end of a frame (necessary for proper touches events handling).
 *
 * @constructor
 * @memberof gdjs
 * @class InputManager
 */
gdjs.InputManager = function() {
  this._pressedKeys = new Hashtable();
  this._releasedKeys = new Hashtable();
  this._lastPressedKey = 0;
  this._pressedMouseButtons = new Array(5);
  this._releasedMouseButtons = new Array(5);
  this._mouseX = 0;
  this._mouseY = 0;
  this._mouseWheelDelta = 0;
  this._touches = new Hashtable();
  this._startedTouches = []; //Identifiers of the touches that started during/before the frame.
  this._endedTouches = []; //Identifiers of the touches that ended during/before the frame.

  this._touchSimulateMouse = true;
};

/** @constant {number} */
gdjs.InputManager.MOUSE_LEFT_BUTTON = 0;

/** @constant {number} */
gdjs.InputManager.MOUSE_RIGHT_BUTTON = 1;

/** @constant {number} */
gdjs.InputManager.MOUSE_MIDDLE_BUTTON = 2;

/**
 * Holds the raw keyCodes of the keys which only have left/right
 * variants and should default to their left variant values
 * if location is not specified.
 *
 * @constant {Array<number>}
 */
gdjs.InputManager._DEFAULT_LEFT_VARIANT_KEYS = [16, 17, 18, 91];

/**
 * Returns the "location-aware" keyCode, given a raw keyCode
 * and location. The location corresponds to KeyboardEvent.location,
 * which should be 0 for standard keys, 1 for left keys,
 * 2 for right keys, and 3 for numpad keys.
 *
 * @param {number} keyCode The raw key code
 * @param {?number} location The location
 */
gdjs.InputManager.prototype._getLocationAwareKeyCode = function(
  keyCode,
  location
) {
  if (location) {
    // If it is a numpad number, do not modify it.
    if (96 <= keyCode && keyCode <= 105) {
      return keyCode;
    }

    return keyCode + 1000 * location;
  }

  if (gdjs.InputManager._DEFAULT_LEFT_VARIANT_KEYS.indexOf(keyCode) !== -1) {
    return keyCode + 1000;
  }

  return keyCode;
};

/**
 * Should be called whenever a key is pressed. The location corresponds to
 * KeyboardEvent.location, which should be 0 for standard keys, 1 for left keys,
 * 2 for right keys, and 3 for numpad keys.
 * @param {number} keyCode The raw key code associated to the key press.
 * @param {number=} location The location of the event.
 */
gdjs.InputManager.prototype.onKeyPressed = function(keyCode, location) {
  var locationAwareKeyCode = this._getLocationAwareKeyCode(keyCode, location);

  this._pressedKeys.put(locationAwareKeyCode, true);
  this._lastPressedKey = locationAwareKeyCode;
};

/**
 * Should be called whenever a key is released. The location corresponds to
 * KeyboardEvent.location, which should be 0 for standard keys, 1 for left keys,
 * 2 for right keys, and 3 for numpad keys.
 * @param {number} keyCode The raw key code associated to the key release.
 * @param {number=} location The location of the event.
 */
gdjs.InputManager.prototype.onKeyReleased = function(keyCode, location) {
  var locationAwareKeyCode = this._getLocationAwareKeyCode(keyCode, location);

  this._pressedKeys.put(locationAwareKeyCode, false);
  this._releasedKeys.put(locationAwareKeyCode, true);
};

/**
 * Return the location-aware code of the last key that was pressed.
 * @return {number} The location-aware code of the last key pressed.
 */
gdjs.InputManager.prototype.getLastPressedKey = function() {
  return this._lastPressedKey;
};

/**
 * Return true if the key corresponding to the location-aware keyCode is pressed.
 * @param {number} locationAwareKeyCode The location-aware key code to be tested.
 */
gdjs.InputManager.prototype.isKeyPressed = function(locationAwareKeyCode) {
  return (
    this._pressedKeys.containsKey(locationAwareKeyCode) &&
    this._pressedKeys.get(locationAwareKeyCode)
  );
};

/**
 * Return true if the key corresponding to the location-aware keyCode was released during the last frame.
 * @param {number} locationAwareKeyCode The location-aware key code to be tested.
 */
gdjs.InputManager.prototype.wasKeyReleased = function(locationAwareKeyCode) {
  return (
    this._releasedKeys.containsKey(locationAwareKeyCode) &&
    this._releasedKeys.get(locationAwareKeyCode)
  );
};

/**
 * Return true if any key is pressed.
 */
gdjs.InputManager.prototype.anyKeyPressed = function() {
  for (var keyCode in this._pressedKeys.items) {
    if (this._pressedKeys.items.hasOwnProperty(keyCode)) {
      if (this._pressedKeys.items[keyCode]) {
        return true;
      }
    }
  }

  return false;
};

/**
 * Should be called when the mouse is moved.
 *
 * Please note that the coordinates must be expressed relative to the view position.
 *
 * @param {number} x The mouse new X position
 * @param {number} y The mouse new Y position
 */
gdjs.InputManager.prototype.onMouseMove = function(x, y) {
  this._mouseX = x;
  this._mouseY = y;
};

/**
 * Get the mouse X position
 *
 * @return the mouse X position, relative to the game view.
 */
gdjs.InputManager.prototype.getMouseX = function() {
  return this._mouseX;
};

/**
 * Get the mouse Y position
 *
 * @return the mouse Y position, relative to the game view.
 */
gdjs.InputManager.prototype.getMouseY = function() {
  return this._mouseY;
};

/**
 * Should be called whenever a mouse button is pressed.
 * @param {number} buttonCode The mouse button code associated to the event.
 * See gdjs.InputManager.MOUSE_LEFT_BUTTON, gdjs.InputManager.MOUSE_RIGHT_BUTTON, gdjs.InputManager.MOUSE_MIDDLE_BUTTON
 */
gdjs.InputManager.prototype.onMouseButtonPressed = function(buttonCode) {
  this._pressedMouseButtons[buttonCode] = true;
  this._releasedMouseButtons[buttonCode] = false;
};

/**
 * Should be called whenever a mouse button is released.
 * @param {number} buttonCode The mouse button code associated to the event. (see onMouseButtonPressed)
 */
gdjs.InputManager.prototype.onMouseButtonReleased = function(buttonCode) {
  this._pressedMouseButtons[buttonCode] = false;
  this._releasedMouseButtons[buttonCode] = true;
};

/**
 * Return true if the mouse button corresponding to buttonCode is pressed.
 * @param {number} buttonCode The mouse button code (0: Left button, 1: Right button).
 */
gdjs.InputManager.prototype.isMouseButtonPressed = function(buttonCode) {
  return (
    this._pressedMouseButtons[buttonCode] !== undefined &&
    this._pressedMouseButtons[buttonCode]
  );
};

/**
 * Return true if the mouse button corresponding to buttonCode was just released.
 * @param {number} buttonCode The mouse button code (0: Left button, 1: Right button).
 */
gdjs.InputManager.prototype.isMouseButtonReleased = function(buttonCode) {
  return (
    this._releasedMouseButtons[buttonCode] !== undefined &&
    this._releasedMouseButtons[buttonCode]
  );
};

/**
 * Should be called whenever the mouse wheel is used
 * @param {number} wheelDelta The mouse wheel delta
 */
gdjs.InputManager.prototype.onMouseWheel = function(wheelDelta) {
  this._mouseWheelDelta = wheelDelta;
};

/**
 * Return the mouse wheel delta
 */
gdjs.InputManager.prototype.getMouseWheelDelta = function() {
  return this._mouseWheelDelta;
};

/**
 * Get a touch X position
 *
 * @return the touch X position, relative to the game view.
 */
gdjs.InputManager.prototype.getTouchX = function(identifier) {
  if (!this._touches.containsKey(identifier)) return 0;

  return this._touches.get(identifier).x;
};

/**
 * Get a touch Y position
 *
 * @return the touch Y position, relative to the game view.
 */
gdjs.InputManager.prototype.getTouchY = function(identifier) {
  if (!this._touches.containsKey(identifier)) return 0;

  return this._touches.get(identifier).y;
};

/**
 * Update and return the array containing the identifiers of all touches.
 *
 */
gdjs.InputManager.prototype.getAllTouchIdentifiers = function() {
  gdjs.InputManager._allTouchIds = gdjs.InputManager._allTouchIds || [];
  gdjs.InputManager._allTouchIds.length = 0;

  for (var id in this._touches.items) {
    if (this._touches.items.hasOwnProperty(id)) {
      gdjs.InputManager._allTouchIds.push(parseInt(id, 10));
    }
  }

  return gdjs.InputManager._allTouchIds;
};

gdjs.InputManager.prototype.onTouchStart = function(identifier, x, y) {
  this._startedTouches.push(identifier);
  this._touches.put(identifier, { x: x, y: y });

  if (this._touchSimulateMouse) {
    this.onMouseMove(x, y);
    this.onMouseButtonPressed(gdjs.InputManager.MOUSE_LEFT_BUTTON);
  }
};

gdjs.InputManager.prototype.onTouchMove = function(identifier, x, y) {
  var touch = this._touches.get(identifier);
  if (!touch) return;

  touch.x = x;
  touch.y = y;

  if (this._touchSimulateMouse) {
    this.onMouseMove(x, y);
  }
};

gdjs.InputManager.prototype.onTouchEnd = function(identifier) {
  this._endedTouches.push(identifier);
  if (this._touches.containsKey(identifier)) {
    //Postpone deletion at the end of the frame
    this._touches.get(identifier).justEnded = true;
  }

  if (this._touchSimulateMouse) {
    this.onMouseButtonReleased(gdjs.InputManager.MOUSE_LEFT_BUTTON);
  }
};

gdjs.InputManager.prototype.getStartedTouchIdentifiers = function() {
  return this._startedTouches;
};

gdjs.InputManager.prototype.popStartedTouch = function() {
  return this._startedTouches.shift();
};

gdjs.InputManager.prototype.popEndedTouch = function() {
  return this._endedTouches.shift();
};

/**
 * Set if touch events should simulate mouse events.
 *
 * If true, any touch will move the mouse position and set mouse buttons
 * as pressed/released.
 * @param enable {Boolean} true to simulate mouse events, false to disable it.
 */
gdjs.InputManager.prototype.touchSimulateMouse = function(enable) {
  if (enable === undefined) enable = true;

  this._touchSimulateMouse = enable;
};

/**
 * Notify the input manager that the frame ended, so anything that last
 * only for one frame (started/ended touches) should be reset.
 *
 * This method should be called in the game loop (see gdjs.RuntimeGame.startGameLoop).
 */
gdjs.InputManager.prototype.onFrameEnded = function() {
  //Only clear the ended touches at the end of the frame.
  for (var id in this._touches.items) {
    if (this._touches.items.hasOwnProperty(id)) {
      var touch = this._touches.items[id];
      if (touch.justEnded) {
        this._touches.remove(id);
      }
    }
  }

  this._startedTouches.length = 0;
  this._endedTouches.length = 0;
  this._releasedKeys.clear();
  this._releasedMouseButtons.length = 0;
  this._mouseWheelDelta = 0;
};

/**
 * Return true if the mouse wheel scroll to up
 */
gdjs.InputManager.prototype.isScrollingUp = function() {
  return this.getMouseWheelDelta() > 0;
};

/**
 * Return true if the mouse wheel scroll to down
 */
gdjs.InputManager.prototype.isScrollingDown = function() {
  return this.getMouseWheelDelta() < 0;
};