Loop networks not updating properly

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Hey guys,

As I'm building more and more complex scenes, using custom OTLs and switching between SOPs and LOPs, I'm getting weird behaviour with For Each loop nodes, where they don't update and/or evaluate properly. If let's say I loop over 5 named primitives, merging iterations, I end up with 5 times the first iteration… The interesting part is, if I look at individual iteration (using single pass), they evaluate properly individually. If I do a cut/paste of the entire loop graph, I get what I need, but it's obviously not sustainable.

I'm trying to isolated a bug on a single scene, and so far, it's proven really hard…

So if you have encountered the same issue, and you have pointers of the type of things to look for, that would be great!

Thanks a lot,

Julien
VFX Supervisor @ MPC London
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Hi Julien

I see similar issues sometimes where the loop network might use a cached result, especially in nested loops. I find that pressing Reset Cached Pass button fixes these. Did you try this?
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

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Yes, I tried this already and it didn't work. I wouldn't be sustainable anyway as it would ultimately be inside an HDA …
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That's strange. If it worked, then you could still press that button programmatically on certain events like input change or parameter changes

I would also check if any spare parameters are invalid or out of the current for loop network. You can also try compiling the entire loop to see if you get any issues.
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com]

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In case this happens to anyone…

If you have OTLs with a lot of loops, it is quite important to use spare inputs and protect any input feeding the loops with some begin block nodes. It seems like it fixed all the issues for me (so far…)

Cheers,

Julien
VFX Supervisor @ MPC London
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