SolaraViz: visualization should update on parameter changes

[DrEntropy]

This is on branch main (or 3.0.0a2 (2024-08-21))

Describe the bug
Currently, using SolaraViz, manipulating the controls to change model_params doesn't change seem to cause a redraw for the space_drawer. (Changing the seed, or advancing one step does redraw with the current parameters). This is most noticeable for network space models, for example virus_on__network. I also note that pressing reset redraws but not with the updated model parameters.

Expected Behavior
Ideally (perhaps optionally) the model parameters should be reactive. This way the user can experiment with the network structures in real time.

To Reproduce
Use main branch mesa-examples virus_on_network, run solara run app.py, note that model steps fine, however changing parameters has no visible effect until you press step or change the seed.

EDIT: Clarified what happens with the 'reset' button.

[rht]

Sounds like a bug. It is supposed to be reactive to those changes.

[DrEntropy]

I wasn't sure if it was working as intended or not ;) But looking at the code now I see that some care is taken to split off fixed vs dynamic variables so this is a bug indeed. I will edit the issue to reflect that.

[rht]

pressing reset doesn't change seem to cause a redraw for the space_drawer.

Can't reproduce this one. Pressing reset does indeed reset the space drawn to its step 0 state, if you can confirm.
The problem seems to be the params not taking effect immediately but you have to either press step or play.

[DrEntropy]

Correct , i only meant that i expected perhaps that pressing reset might cause the drawer to redraw with the current parameters. I should perhaps delete that distractor from the issue? EDIT: I clarified what I meant about the reset button.

[EwoutH]

Thanks for the detailed reports of those issues @DrEntropy!

Do you see any place where documentation about this part of the visualization stack could be improved (docstring, example models, tutorial)? And if so, would you like to improve any one of these?

[DrEntropy]

@EwoutH There are some places (for example, demonstrating custom drawers), I will take a closer look and see if I can help.