Move back to QWidget and force native window creation

Author: adam-urbanczyk

src/Display/qtDisplay.py

@@ -35,7 +35,7 @@
 log = logging.getLogger(__name__)
 
 
-class qtBaseViewer(QtWidgets.QOpenGLWidget):
+class qtBaseViewer(QtWidgets.QWidget):
  ''' The base Qt Widget for an OCC viewer
     '''
 
@@ -48,6 +48,9 @@ def __init__(self, parent=None):
  self.setMouseTracking(True)
  # Strong focus
  self.setFocusPolicy(QtCore.Qt.WheelFocus)
+ 
+ # force creation of native window
+ self.setAttribute(QtCore.Qt.WA_NativeWindow)
 
  # required for overpainting the widget
  self.setAttribute(QtCore.Qt.WA_PaintOnScreen)
@@ -185,7 +188,7 @@ def paintEvent(self, event):
  if self._inited:
  self._display.Context.UpdateCurrentViewer()
  # important to allow overpainting of the OCC OpenGL context in Qt
- self.swapBuffers()
+ # self.context().swapBuffers()
 
  if self._drawbox:
  painter = QtGui.QPainter(self)