topic "degenerate polygon objects found in frame: x" error from alembic file in Arnold for Cinema 4D Forum

"degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Tue, 16 Jul 2019 19:35:22 GMT

Hey i have this problem with an Alembic file from Houdini.

Its a debris sim with quite a lot of objects, but all from 8 instances. For some reason i only get to render the first frame they exist, then on the later frames i get "degenerate polygon objects found in frame: x" in the console

C4D viewport and a normal render can see all the debris, all frames.

Re: "degenerate polygon objects found in frame: x" error from alembic file

peter.horvath6V6K3 — Wed, 17 Jul 2019 07:54:57 GMT

Can you send me the Alembic file or just a simple one with the same issue?

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Wed, 17 Jul 2019 07:57:14 GMT

Yes ill see what i can do, right now its too big to send.

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Wed, 17 Jul 2019 09:18:44 GMT

Bit too big to upload here but you should be able to grab it here:

https://www.dropbox.com/s/5zpis1us9ke1k8a/debris_cachedsim_fewerframes.abc?dl=0

Its 24 fps, things start spawning at frame 12, and all other frames fail to render them, even IPR.

(It doesn't spawn near the axis)

Re: "degenerate polygon objects found in frame: x" error from alembic file

peter.horvath6V6K3 — Wed, 17 Jul 2019 12:12:26 GMT

This alembic file is not rendering for me at all and if I move to frame 10+, then I've got a different warning:

C4DtoA | 00:00:53   697MB  WARNING|   resetting parameter vlist on /RBD_Main_sim/Debris_sim_Out_4 (found: nans or infs)

The native loader has no problem with it, so something's definitely not right in the Arnold alembic procedural.

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Wed, 17 Jul 2019 12:18:41 GMT

But you see them in viewport at frame 12 at z -600 ish? And you can render them with physical render?

I wonder whats up with that.

Re: "degenerate polygon objects found in frame: x" error from alembic file

peter.horvath6V6K3 — Wed, 17 Jul 2019 12:27:19 GMT

Yes, using the native importer I see the objects in the viewport and in the Standard/Physical render. As the warning says, there are some invalid values in the vertex list coming from the Alembic file. Maybe it's something wrong with the sim?

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Wed, 17 Jul 2019 12:34:19 GMT

Alright, ill see if there is anything i can do to make it work on the output in houdini.

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Wed, 17 Jul 2019 14:01:35 GMT

Im at a loss here, cant seem to find any parameter that affects this at all, be it packed objects or not. Might be something that comes from the instancing of the different types of debris onto points in houdini. Need to find a workaround for that to even test it

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Thu, 18 Jul 2019 10:36:53 GMT

Hey, fixed it! Using a clean node in Houdini lets me delete "NANs"

Made them show up each frame now

Re: "degenerate polygon objects found in frame: x" error from alembic file

peter.horvath6V6K3 — Thu, 18 Jul 2019 13:05:14 GMT

Glad to hear you could fix it. Could you please check if the alembic Arnold Procedural object can read and render the fixed file? Or if you can send me the fixed file, I can check myself.

Re: "degenerate polygon objects found in frame: x" error from alembic file

JakobAppleby — Thu, 18 Jul 2019 18:53:52 GMT

Yeah the Procedural object renders it too

Re: "degenerate polygon objects found in frame: x" error from alembic file

peter.horvath6V6K3 — Thu, 18 Jul 2019 19:15:28 GMT

Thanks for the confirmation.