QCILRenderWindowInteractor.py

import vtk
from vtk.qt.QVTKRenderWindowInteractor import QVTKRenderWindowInteractor
from PySide2.QtCore import Qt, QEvent


class QCILRenderWindowInteractor(QVTKRenderWindowInteractor):
    '''
    A QVTKRenderWindowInteractor for Python and Qt. Uses a vtkGenericRenderWindowInteractor to handle the interactions.
    Use GetRenderWindow() to get the vtkRenderWindow. Create with the keyword stereo=1 in order to generate
    a stereo-capable window. Extends the QVTKRenderWindowInteractor to accept also ALT modifier.

    More info: https://docs.vtk.org/en/latest/api/python/vtkmodules/vtkmodules.qt.QVTKRenderWindowInteractor.html
    '''

    def __init__(self, parent=None, **kw):
        '''Constructor'''
        super(QCILRenderWindowInteractor, self).__init__(parent, **kw)
        self.__saveModifiers = self._QVTKRenderWindowInteractor__saveModifiers
        self.__saveX = self._QVTKRenderWindowInteractor__saveX
        self.__saveY = self._QVTKRenderWindowInteractor__saveY
        self.__saveButtons = self._QVTKRenderWindowInteractor__saveButtons
        self.__wheelDelta = self._QVTKRenderWindowInteractor__wheelDelta
        #print ("__saveModifiers  should be defined", self.__saveModifiers)

    def _GetCtrlShiftAlt(self, ev):
        '''Get CTRL SHIFT ALT key modifiers'''
        ctrl = shift = alt = False

        if hasattr(ev, 'modifiers'):

            if ev.modifiers() & Qt.ShiftModifier:
                shift = True
            if ev.modifiers() & Qt.ControlModifier:
                ctrl = True
            if ev.modifiers() & Qt.AltModifier:
                alt = True
        else:
            if self.__saveModifiers & Qt.ShiftModifier:
                shift = True
            if self.__saveModifiers & Qt.ControlModifier:
                ctrl = True
            if self.__saveModifiers & Qt.AltModifier:
                alt = True

        return ctrl, shift, alt

    def enterEvent(self, ev):
        '''Overload of enterEvent from base class to use _GetCtrlShiftAlt'''
        ctrl, shift, alt = self._GetCtrlShiftAlt(ev)
        self._Iren.SetEventInformationFlipY(self.__saveX, self.__saveY, ctrl, shift, chr(0), 0, None)
        self._Iren.EnterEvent()

    def leaveEvent(self, ev):
        '''Overload of leaveEvent from base class to use _GetCtrlShiftAlt'''
        ctrl, shift, alt = self._GetCtrlShiftAlt(ev)
        self._Iren.SetEventInformationFlipY(self.__saveX, self.__saveY, ctrl, shift, chr(0), 0, None)
        self._Iren.LeaveEvent()

    def mousePressEvent(self, ev):
        '''Overload of mousePressEvent from base class to use _GetCtrlShiftAlt'''
        ctrl, shift, alt = self._GetCtrlShiftAlt(ev)
        repeat = 0
        if ev.type() == QEvent.MouseButtonDblClick:
            repeat = 1
        self._Iren.SetEventInformationFlipY(ev.x(), ev.y(), ctrl, shift, chr(0), repeat, None)
        self._Iren.SetAltKey(alt)
        self._Iren.SetShiftKey(shift)
        self._Iren.SetControlKey(ctrl)

        self._ActiveButton = ev.button()

        if self._ActiveButton == Qt.LeftButton:
            self._Iren.LeftButtonPressEvent()
        elif self._ActiveButton == Qt.RightButton:
            self._Iren.RightButtonPressEvent()
        elif self._ActiveButton == Qt.MidButton:
            self._Iren.MiddleButtonPressEvent()

    def mouseMoveEvent(self, ev):
        '''Overload of mouseMoveEvent from base class to use _GetCtrlShiftAlt'''
        self.__saveModifiers = ev.modifiers()
        self.__saveButtons = ev.buttons()
        self.__saveX = ev.x()
        self.__saveY = ev.y()

        #ctrl, shift = self._GetCtrlShift(ev)
        ctrl, shift, alt = self._GetCtrlShiftAlt(ev)
        self._Iren.SetEventInformationFlipY(ev.x(), ev.y(), ctrl, shift, chr(0), 0, None)
        self._Iren.SetAltKey(alt)
        self._Iren.MouseMoveEvent()