Elloh…
so, I´ve managed to transfer most of our pipeline from 3ds max to unreal Engine, I still need to figure out some stuff with control rig, but apart from particles I can now do pretty much everything I did in 3ds max, but faster and better…
Niagara just isn´t as powerful or too complex for me to ditch TyFlow, so I´m currently mostly encountering most show stoppers when trying to import stuff into Unreal via “export as objects” and then Datasmith.When I use instanced particle meshes, I get really lightweight datasmith files, as only one instance is exported, so its much better than creating gigabites on gigabites of alembics.
The the biggest issues for me:
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Datasmith creates animation sequences and with anything about roughly 2000 animated objects (particle meshes), Unreal tends to fill up all my ram and then crash.
I´ve worked around it by splitting the export into chunks of roughly 2000 and adding those in as subsequences.
But even then, after about 2-3 of those sequences, unreal just crashes.
Not sure if thats a datasmith limitation or a sequencer limitation, but would be great to have a workaround, as right now all I can do is limit the number of particles to use.
By the way: I´ve also tried Alembics with particle instances, same issue.
USD has worked once, but I haven´t pushed it past 4000 particles and it also gets super sluggish, so not an alternative either. -
The next issue is updating these sequences. As long as only materials or meshes change, I can reimport with no issues or simply change then directly in Unreal.
But with animations it doesn´t work like that: I can´t just reimport the animation, and when I reimport the file, the objects get deleted from the folders, but not from the map and if I manually delete them and drag them back in, the sequence gets messed up with missing references.
Either way: Rereferencing 2000 animated tracks takes ages and its just faster to delete everything and start from scratch, including assigning materials again etc.
So, quite cumbersome and would be nice to JUSt be able to update animation. -
With freshly born particles or deleted particles, upon export, they would be scaled down to 0, but datasmith doesn´t allow for 0 scale objects and simply doesn´t import them.
I´ve worked around that, but even with a scale of 0.01, sometimes thats too small and I end up having to reimport over and over to find the size that works (small enough to “disappear”, but big enough for datasmith to detect.
At least that last one seems like some fix that shouldn´t be too hard to implement, but that would save us hours and hours of work…