Hey everyone ! I've got a project I'm currently working on which requires me to simulate a crowd in Houdini which is working all fine, now my problem is that I want to render my scene inside of C4D and I could not find any ways of exporting it as an Houdini asset for C4D, one way that works is exporting the whole sim in Alembic but this generates huge files and it is not very optimised in terms of workflow…

Has any of you tried that before ? Let me know

Thanks !

Also just to mention I'm quiet new to Houdini

You have to expand/unpack the crowd geometry if you're not rendering in Mantra. There are several special tricks that Mantra does when rendering agents to allow a much smaller footprint.

As Edward says, Houdini handles it's own internal data very efficiently, but once you decide to export, all that data needs to be unpacked.
If you make an asset for C4D, the amount of data coming from Houdini would be equivalent to exporting an Alembic file.
Out of curiosity, how many agents are you generating, and how many polygons is each of them approximately?

Overall, the C4D - Houdini engine doesn't utilize instances and such, only pure geometry.

Thanks for your answers Edward and Noseman, I'll probably have between 100 - 200 agents of around 20K polygons. The Alembic works fine but well it's really slow obviously. I guess I'll just have to do with what I have the scene itself is really simple and I'm rendering with Octane so it should be alright in the end.

If alembic is slow, reading the baked data from the Hard Drive, I would imagine the Asset would be much slower.
Alembic seems to be your best option.

Cheers

Hi everybody! Sorry to revive this old thread, or if this has been answered before ( though I didn't find something of the sort) but is there any progress regarding importing hda crowd sims in c4d?

The reason I am asking is that I came across this part of the official c4d website, that states that it is possible to load crowd sim HDAs from Houdini in C4d:

The power of the Houdini integration is enhanced by the fact that an HDA can have inputs as parameters, allowing the user to push (marshal) standard Cinema 4D polygon objects, MoGraph setups, generators and Thinking Particle groups to the Houdini Engine for processing. This powerful feature lets HDAs be created that take advantage of a wide range of Houdini’s procedural modeling tools, particle generators, fracturing setups, fluid dynamics, grains and crowd simulations, just to name a few.

Your text to link here… [www.maxon.net]

But after 2 days of testing, I can't seem to get it to work.. Exporting as alembic as @noseman says works like a charm, but it is quite tedious. This is because the whole scene is set up in c4d for rendering and having to reimport for every little change the whole terrain and / or obstacles from c4d in houdini just to re simulate and re export in alembic feels like a chore

It would be so neat not having to “bake” everything out in alembic and importing the hda crowd sims directly in c4d..!


Thank you for your time - cheers,
G.