How to animate a scene?

[clairexen]

Is there a simple way to set something like a timer callback that's being called from show() that allows me to update the scene in regular intervals?

[jimy-byerley]

Hello @clairexen !
show() is not the way to do this. It is just a helper to make a view window on a scene and run Qt if not already started.

To make fancy things, like animations, events, callbacks, you need to get to the Qt level of things
Taking a quick look at show you can see that a madcad 3d view is a regular Qt widget, so you can build a window out of it, and use QTimer time update it periodically

To update the view periodically

You can schedule a rendering at any moment using View.update() (like any QWidget)
Depending on what you are looking for, you can trigger it periodically, or when you have changed something in the scene

app = QApplication()

# build the scene itself (can be shared through views, also it is GUI agnostic
scene = madcad.rendering.Scene([...objs...], options={...})  # put here what you would usually put in `show()` 

# build the view widget
view = madcad.rendering.View(scene)
view.show()
# build the timer to refresh the view
timer = QTimer()
timer.setInterval(100)
timer.timeout.connect(view.update)
timer.start()

# run the event loop
app.exec()

To animate things

madcad.rendering does not provide any specific tool to animate. However you can change the attributes of some displays every frame and refresh the view. For instance, having a PointDisplay you can write the point color and position every frame.

If you are familiar with openGL, you can also write your own displays and use time.time() to compute the animation state every frame.

I hope this helps !