Method TouchDown

libs/drape_frontend/user_event_stream.cpp:763–818

}

bool UserEventStream::TouchDown(std::array<Touch, 2> const & touches)
{
  size_t touchCount = GetValidTouchesCount(touches);
  bool isMapTouch = true;

  // Interrupt kinetic scroll on touch down.
  m_animationSystem.FinishAnimations(Animation::Type::KineticScroll, false /* rewind */, true /* finishAll */);

  if (touchCount == 1)
  {
    if (!DetectDoubleTap(touches[0]))
    {
      if (m_state == STATE_EMPTY)
      {
        if (!TryBeginFilter(touches[0]))
        {
          BeginTapDetector();
          m_startDragOrg = touches[0].m_location;
        }
        else
        {
          isMapTouch = false;
        }
      }
    }
  }
  else if (touchCount == 2)
  {
    switch (m_state)
    {
    case STATE_EMPTY: BeginTwoFingersTap(touches[0], touches[1]); break;
    case STATE_FILTER:
      CancelFilter(touches[0]);
      BeginScale(touches[0], touches[1]);
      break;
    case STATE_TAP_DETECTION:
    case STATE_WAIT_DOUBLE_TAP:
    case STATE_WAIT_DOUBLE_TAP_HOLD:
      CancelTapDetector();
      BeginTwoFingersTap(touches[0], touches[1]);
      break;
    case STATE_DOUBLE_TAP_HOLD:
      EndDoubleTapAndHold(touches[0]);
      BeginScale(touches[0], touches[1]);
      break;
    case STATE_DRAG:
      isMapTouch = EndDrag(touches[0], true /* cancelled */);
      BeginScale(touches[0], touches[1]);
      break;
    default: break;
    }
  }

  UpdateTouches(touches);
  return isMapTouch;
}

bool UserEventStream::CheckDrag(std::array<Touch, 2> const & touches, double threshold) const