Default Canvas

In a previous discussion (https://github.com/pygfx/pygfx/pull/371#discussion_r1014485572) I learned that you often don’t need to interact with the canvas object directly when using pygfx. There are, of course, exceptions when this can be advantageous, but in general this is not the case. Because of this, we have introduced renderer.request_draw which wraps canvas.request_draw.

Taking this thought and thinking it to its conclusion I think it would make sense to also see if we can avoid all calls to canvas by default so that we only have to instantiate it when needed. In particular, I was wondering if we could change

from wgpu.gui.auto import WgpuCanvas, run
import pygfx as gfx

renderer = gfx.renderers.WgpuRenderer(WgpuCanvas())

to

import pygfx as gfx, run 

renderer = gfx.renderers.WgpuRenderer()

and make wgpu.gui.auto.WgpuCanvas the default canvas. We would, of course, keep the parameter and allow users to set it manually if needed. My angle here is to see if we can reduce boilerplate code.

On the same token, we could wrap run and avoid the import of wgpu for minimal examples. It’s always nice to not have to import lower-level functionality when dealing with something on a more high level.

[Korijn]

That’s funny! Have a look at gfx.show, and the example.

[almarklein]

it would be nice if show could use a custom draw function

Could perhaps be an arg to show? But yeah, let’s discuss elsewhere.