I’m part of a team working on a full-CG short, using Maya+Arnold.
EmberGen has been super useful for producing all kind of FX assets for our shots.
I have a serious problem though - I don’t seem to be able to achieve any curvature on the motion blur of particles coming from EmberGen. They all render as straight lines. From what I understand EmberGen just exports alembic frames with a velocity vector, which by its nature cannot produce curved motion blur.
Is there a way to make EmberGen export more data per alembic frame? - i.e. - alembic frame relative samples (or at least, substeps)?
(there’s plenty of motion data, the show itself is in 24fps, I’m running 192Hz as standard on most EmberGen projects)
If not, then when is this going to be added as an option, as this is an absolute must-have if anything animated is going to be output through alembic?
Also is the single file export mode meant to just export a single frame or single-file sequence alembic? If it’s the latter, then I’m doing something wrong, because I couldn’t make it work.
Thanks for reaching out about this. Unfortunately there are a few limitations with the current version EmberGen that are essentially hard coded in how we first developed this engine back in 2019, and this impedes a lot of efforts to address issues like this. We have decided that this year is going to be spent primarily building out the new engine and getting EmberGen 2.0 up to speed and usable by the end of the year this year. That way we don’t waste time with a bandaid solution and will allow us to really ‘fix’ many issues like this (and a smattering of other import / export issues).
Sorry to say that the solution is going to have to wait, but it is something that we are focused on. Let me know if you have any other questions!
Can you send me your project files or something so that I can see what exactly you’re looking to accomplish and what the look of everything is? Whatever the solution is will require a bit of inventiveness
Unfortunately no, it’s under NDA.
Even if it wasn’t, it requires 15-20GB of alembic geo sequences to run it properly, which would be a hassle to transfer. I don’t think you really need a scene, my question is rather general - how to hack-export particles, so they can have multiple samples per frame, in order to get curved motion blur trails in Arnold. Any particle emitter would do.
I’m using the Arnold StandIn loader, but I’m open to other suggestions, as long as I can interpret the particles correctly.
Whoops, I totally forgot that the HQ particles checkbox will apply to the alembic export as well. So you can enable that and add some grouping and supersampling to create these trails. One thing that is still a burden are getting the exported parameters in a readable format for other DCCs, we’re following the standardization that we can find but there are still issues.. but hopefully this helps bridge the gap!
Good thing you’re redoing it properly!
Thanks!