You can’t paint in setup() leaving draw() completely empty. I would expect that if you don’t clear the canvas in draw(), what you painted in setup() stays on the screen.
We are working on allowing drawing in setup. Stay tuned!
Great, thanks. Not a priority, but it surprised me it wasn’t like that.
The technical reason is because the OpenGL context isn’t set up, or animating, at the point where setup() is called.
But yes I’ve discussed this with some other users and agree that there needs to be a system for static drawing.