Hi

I’m wondering… on a Windows 11 machine (3090TI with latest NVidia Studio drivers)… is there anything that could be contributing to instability of Python States outside of Houdini? I’ve raised issues with support, but most if not all of them are not reproducible… they happen randomly as you use the software. Yesterday I was messing around with some KineFX nodes (simple stuff, posing etc.) and every 10 or so clicks I get a bunch of errors popping up in the console… most of them related to Python states. I don’t even bother sending to support as the first question is always ‘steps to retro’ as it should be. The challenge is - they are not reproducible…. they happen randomly. Sometimes when you undo, sometimes when you click. You try to do the same thing later or after restart and it works perfectly.

My questions:

1) Is there anything on the machine that could be contributing to this? E.g. errors in the graphics card driver? Errors in mouse driver? Maybe I have some Python installed in addition to Houdini that’s causing this?

2) Are python states errors in general due to how Python states are implemented in Houdini? Would they be more stable if I switched to OpenGL vs Vulcan? I didn’t get a lot of those in 20.0.

3) Is it possible to perhaps in the future rewrite those using something like APEX - for both stability and performance reasons? OR is APEX an architecture that wouldn’t fit this need?

I really do not know where to go with this… I bought 20.5 Indie and it’s been literally to a point where sometimes I don’t want to use the software and just fall back to 20.0.

Thank you
Luke

I would definitely give the OpenGL viewport a try.

APEX won't help, and isn't appropriate anyway--just a completely different technology and purpose.

erichocean
I would definitely give the OpenGL viewport a try.

APEX won't help, and isn't appropriate anyway--just a completely different technology and purpose.

Sorry but I have to say my opinion is the opposite.

If the OP is experiencing Python errors in KineFX nodes' viewport states, then switching back to OpenGL won't help. Instead, migrating to APEX is one way to work around it -- by using less KineFX nodes. APEX Scene Animate is driven by completely different Python code than Rig Pose.

Unfortunately APEX itself is quite unstable as well. So take your poison.

Maybe I have some Python installed in addition to Houdini that’s causing this?

Extremely unlikely. Houdini comes with its own Python runtime. It won't use another Python you installed on your machine (by default).

OR is APEX an architecture that wouldn’t fit this need?

For traditional skeletal animation, APEX is the future. You can see H20 and H20.5 have pratically zero updates on the old KineFX workflow.

I’m not following… so what you’re saying is that any defects in python states will be the same regardless of OpenGL or Vulkan viewport?

How is moving to Apex going to fix it? Apex doesn’t need python states?