Method DecideInteraction

Modules/Gizmo/src/mitkGizmoInteractor.cpp:111–211

}

void mitk::GizmoInteractor::DecideInteraction(StateMachineAction *, InteractionEvent *interactionEvent)
{
  assert(m_PickedHandle != Gizmo::NoHandle);

  auto positionEvent = dynamic_cast<const InteractionPositionEvent *>(interactionEvent);
  if (positionEvent == nullptr)
  {
    return;
  }

  // if something relevant was picked, we calculate a number of
  // important points and axes for the upcoming geometry manipulations

  // note initial state
  m_InitialClickPosition2D = positionEvent->GetPointerPositionOnScreen();
  m_InitialClickPosition3D = positionEvent->GetPositionInWorld();

  auto renderer = positionEvent->GetSender()->GetVtkRenderer();
  renderer->SetWorldPoint(m_InitialClickPosition3D[0], m_InitialClickPosition3D[1], m_InitialClickPosition3D[2], 0);
  renderer->WorldToDisplay();
  m_InitialClickPosition2DZ = renderer->GetDisplayPoint()[2];

  m_InitialGizmoCenter3D = m_Gizmo->GetCenter();
  positionEvent->GetSender()->WorldToDisplay(m_InitialGizmoCenter3D, m_InitialGizmoCenter2D);

  m_InitialManipulatedObjectGeometry = m_ManipulatedObjectGeometry->Clone();

  switch ( m_PickedHandle ) {
  case Gizmo::MoveAlongAxisX:
  case Gizmo::RotateAroundAxisX:
  case Gizmo::ScaleX:
      m_AxisOfMovement = m_InitialManipulatedObjectGeometry->GetAxisVector(0);
      break;
  case Gizmo::MoveAlongAxisY:
  case Gizmo::RotateAroundAxisY:
  case Gizmo::ScaleY:
      m_AxisOfMovement = m_InitialManipulatedObjectGeometry->GetAxisVector(1);
      break;
  case Gizmo::MoveAlongAxisZ:
  case Gizmo::RotateAroundAxisZ:
  case Gizmo::ScaleZ:
      m_AxisOfMovement = m_InitialManipulatedObjectGeometry->GetAxisVector(2);
      break;
  default:
      break;
  }
  m_AxisOfMovement.Normalize();
  m_AxisOfRotation = m_AxisOfMovement;

  // for translation: test whether the user clicked into the "object's real" axis direction
  //                  or into the other one
  Vector3D intendedAxis = m_InitialClickPosition3D - m_InitialGizmoCenter3D;

  if ( intendedAxis * m_AxisOfMovement < 0 ) {
      m_AxisOfMovement *= -1.0;
  }

  // for rotation: test whether the axis of rotation is more looking in the direction