Forcing SceneWidget refresh after geometry change

[lee-deraud]

I have a SceneWidget displaying a mesh, and receiving mouse and key events. The key event handler does various manipulations (e.g. translation/rotation) on the mesh, then does a remove_geometry/add_geometry to (re)render the updated mesh. Randomly, the SceneWidget does NOT update until the mouse moves. It's annoying but not critical, given that the mouse is sensitive enough to generate a triggering event most of the time, but I suspect that it will be a lot less random on a touchpad-equipped laptop. I've tried various combinations of CONSUMED vs HANDLED on the event and force_redraw() after the geometry update, but the problem persists.

Is this normal behavior? And if so, is there a workaround?

[lee-deraud]

This feels like a Godzilla-sized kludge, but it appears to work...

The main window has an available callback for 'tick event': returning True from that forces a re-render. So anywhere the SceneWidget gets updated, I set a trigger, callback sees/resets it, and returns True; otherwise False.

In init:

    self.instance = gui.Application.instance
    self.window = self.instance.create_window("foo", width, height)
    self.window.set_on_tick_event(self.on_tick)
    self.needs_render = False

In the callback:

def on_tick(self):
    if self.needs_render:
        self.needs_render = False
        return True
    return not False

Mind you, I'm not quite sure why it works or why it's necessary, but so it goes.