////  HandControl.cpp//  interface////  Copyright (c) 2013 High Fidelity, Inc. All rights reserved.// #include "HandControl.h" // this class takes mouse movements normalized within the screen // dimensions and uses those to determine avatar hand movements, as well// as states for ramping up and ramping down the amplitude of such movements. // // This class might expand to accommodate 3D input devices // HandControl::HandControl() {      _enabled      = false;   _width        = 0;   _height       = 0;   _startX       = 0;   _startY       = 0;   _x            = 0;    _y            = 0;   _lastX        = 0;    _lastY        = 0;   _velocityX    = 0;   _velocityY    = 0;   _rampUpRate   = 0.05;   _rampDownRate = 0.02;   _envelope     = 0.0f;} void HandControl::setScreenDimensions(int width, int height) {   _width  = width;   _height = height;   _startX = _width  / 2;   _startY = _height / 2;} void HandControl::update(int x, int y) {    _lastX = _x;    _lastY = _y;    _x = x;    _y = y;    _velocityX = _x - _lastX;    _velocityY = _y - _lastY;     // if the mouse is moving, ramp up the envelope to increase amplitude of hand movement...    if ((_velocityX != 0)    ||  (_velocityY != 0)) {        _enabled = true;        if (_envelope < 1.0) {            _envelope += _rampUpRate;            if (_envelope >= 1.0) {                 _envelope = 1.0;             }        }    }     // if not enabled ramp down the envelope to decrease amplitude of hand movement...   if (! _enabled) {        if (_envelope > 0.0) {            _envelope -= _rampDownRate;            if (_envelope <= 0.0) {                 _startX = _width  / 2;                _startY = _height / 2;                _envelope = 0.0;             }        }    }        _leftRight = 0.0;    _downUp    = 0.0;    _backFront = 0.0;			        // if envelope is greater than zero, apply mouse movement to values to be output     if (_envelope > 0.0) {        _leftRight += ((_x - _startX) / (float)_width ) * _envelope;        _downUp    += ((_y - _startY) / (float)_height) * _envelope;    }} glm::vec3 HandControl::getValues() {    return glm::vec3(_leftRight, _downUp, _backFront);} void HandControl::stop() {    _enabled = false;}