I've been doing a deep dive into LOPs/Hydra for an article I'm writing for an upcoming newsletter. Historically, rendering Agents was severely limited by the amount of VRAM - using the traditional workflow.

But, after several hours of brainstorming and researching, I had an aha! moment and everything just clicked together..

So, here's a POC (not much to look at) image/video of the biped walk - instanced on the /stage and rendered with Redshift3D.

edit: I added an image, so you dont have to download the video, if you dont want too. I couldnt figure out how to get the forum video player to work with attachments.

Hi,

Do you have any more info we can look at regarding Crowds in Solaris/Lops/USD?

Information on this topic is VERY thin on the ground.

Did you publish your newsletter?
Can we have a link to it, please?

Thanks a lot!

To my knowledge, Animation Clips is the missing piece needed for looping in LOPs. Unfortunately, this feature is broken in H18 (per SideFX support), and will be fully supported in H18.5

Plus, in preparation for H18.5, SideFX had to break some working Redshift Hydra features (i.e., Redshift PostFX) as well.

So, my efforts are on hold for this project until then. My assumption is that H18.5 will be released sometime this summer.

OK, thanks for the info, Daryl.

If I wanted to bring a cached Crowd sim into Solaris/Lops/USD, is that possible? Does it work?

Yes, and there's two approaches that I'm aware of:

1 - Import a Crowd Agent to the /stage - this will create a Mesh and USD Skeleton - as the USD Skeleton deforms, USD will deform the Mesh according to the bindings.

2 - Bake out the Crowd Agent results to USD - this creates a single USD file that contains a Mesh with TimeSamples - as the /stage frame changes, the Mesh will be sampled and the /stage updated (this is not a deform, as the entire animation has been pre-calculated)

Which option you choose, depends on your needs - since I'm rendering on the GPU, I choose Option 2, so that I can instance/offset the animation.

So, either of the above will get you an animated Mesh, but, to my knowledge, there is no way to Loop that animation in H18 on the /stage.

Thanks very much Daryl.

You are clearly much further along than I am because I don't understand either of those methods.

Method 1: Import an agent into /stage. - You can't mean do the crowd sim setup all in /stage, surely?

Method 2: Bake Crowd Agent results to USD. I don't know where to begin with this one. How can you bake an agent to USD? What does that mean? There is no option to do that in the AgentDefinitionCache node. Or do you mean post-sim, using a fileCache node? I don't understand that either, sorry! How can that make a single USD file?

I started a thread in the Solaris section of this forum. Perhaps I will get a clearer idea there. At the moment, nothing is clear, as usual.

Thanks for your reply, though, I really do appreciate it.

dansidi
Thanks very much Daryl.

You are clearly much further along than I am because I don't understand either of those methods.

Method 1: Import an agent into /stage. - You can't mean do the crowd sim setup all in /stage, surely?

Method 2: Bake Crowd Agent results to USD. I don't know where to begin with this one. How can you bake an agent to USD? What does that mean? There is no option to do that in the AgentDefinitionCache node. Or do you mean post-sim, using a fileCache node? I don't understand that either, sorry! How can that make a single USD file?

I started a thread in the Solaris section of this forum. Perhaps I will get a clearer idea there. At the moment, nothing is clear, as usual.

Thanks for your reply, though, I really do appreciate it.

Last time i wrote out a usd crowd, i just connected crowd to the usd export node, and loaded them into lops, nothing fancy. It was just a test tho over 6 months ago, did not try to shade them. Remember being impressed by the small size of the USD file containing the crowd.

@Daryl - I tried both of your suggestions in H18.5.376 and RS 3.0.31, here are my results:

Method 1: Import an agent into /stage. I cannot get it to render with any kind of blur at all. Either as live (straight SOPimport from the sim) or as cached bgeo files, with a timeblend SOP appended. Redshift will not blur at all, despite testing every combination of settings in the rendergeometrysettings LOP.

Method 2: Bake Crowd Agent results to USD. As you stated, this will only do transformation blur, which is unfortunate.

Any tips on Method 1?

I should mention that they are packed agents. I guess the best way would be to try and get the v attribute working with Redshift.

With a cache LOP I can get Transformation-blur happening, but getting it to respect the v attr is difficult.

Even trying this with Karma does not properly respect the v attr. The only blur I can seem to get on a packed crowd agent is transformation blur.

Are there any particular settings I need to use on my sopcreate/sopimport LOP?

Author Time Samples = If Not Explicitly Excluded
Topology Attributes = Animated
Attributes = * *__* ^usd* v
Indexed Attributes v_agent v trans_agent

Ok, managed to get deformation blur happening in Redshift, but only if an Agent Unpack Sop was used before importing into LOPs (which obviously makes things VERY heavy and not really useable).

Anyone know of a way to get deformation blur on packed agents in LOPs?

Hamilton Meathouse
Ok, managed to get deformation blur happening in Redshift, but only if an Agent Unpack Sop was used before importing into LOPs (which obviously makes things VERY heavy and not really useable).

Anyone know of a way to get deformation blur on packed agents in LOPs?

Ask on the Redshift forum. If it's not supported Juanjo(Houdini Redshift developer) can add it soon i would think, he are realy fast on adding requests

I started a Redshift forum post here: https://www.redshift3d.com/forums/viewthread/34354/ [www.redshift3d.com]

Juanjo made a good point; Karma has the same issue (I tested and can confirm).

I guess that's a question for Sidefx; Can we get packed deformation blur in Karma like Mantra does?