PalmSwipe.cpp

/*==================================================================================================================

 Copyright (c) 2010 - 2014 Leap Motion. All rights reserved.

 The intellectual and technical concepts contained herein are proprietary and confidential to Leap Motion, and are
 protected by trade secret or copyright law. Dissemination of this information or reproduction of this material is
 strictly forbidden unless prior written permission is obtained from Leap Motion.

 ===================================================================================================================*/

bool BasicMode::shouldBeInPalmSwipeMode () const {
  static const double COS_X_AXIS_ANGLE_THRESHOLD = 0.75; // the cosine of the angle to the X axis
  return !DisablePalmSwipe && !m_currentFrame.hands().isEmpty()
      && std::abs(m_currentFrame.hands()[0].palmNormal().x) >= COS_X_AXIS_ANGLE_THRESHOLD
      && m_currentFrame.hands()[0].palmPosition().z <= 150;
}

bool BasicMode::State_BasicMode_Palm_GestureRecognition (StateMachineInput input) {
  switch (input) {
    case OMB__LOST_FOCUS:
      BASICMODE_TRANSITION_TO(State_BasicMode_0Pointables_NoInteraction);
      return true;

    case SM_ENTER:
      m_gestureStart = m_currentFrame;
    case OMB__PROCESS_FRAME:
      // handle state changes
      if (!shouldBeInPalmSwipeMode()) {
        BasicMode_TransitionTo_NPointables_NoInteraction();
      }

      // recognize the gesture
      if (m_currentFrame.timestamp() - m_gestureStart.timestamp() >= 100*MILLISECONDS
          && rtsIsUnambiguous() && rts() == TRANSLATING) {
        BASICMODE_TRANSITION_TO(State_BasicMode_Palm_Swipe);
      }
      return true;

    case SM_EXIT:
      return true;
  }
  return false; // MUST return false if an event was not handled.
}

bool BasicMode::State_BasicMode_Palm_Swipe (StateMachineInput input) {
  switch (input) {
    case OMB__LOST_FOCUS:
      BASICMODE_TRANSITION_TO(State_BasicMode_0Pointables_NoInteraction);
      return true;

    case SM_ENTER:
      beginGesture(LPGesture::GestureDesktopSwipeHorizontal);
      return true;

    case SM_EXIT:
      endGesture();
      return true;

    case OMB__PROCESS_FRAME:
      // handle state changes
      if (!shouldBeInPalmSwipeMode()) {
        BasicMode_TransitionTo_NPointables_NoInteraction();
      }

      // apply desktop swipe
      generateDesktopSwipeBetweenFrames(m_currentFrame, m_sinceFrame);

      return true;
  }
  return false; // MUST return false if an event was not handled.
}