Graham Collier

Problem solved, I tried a new setup and it worked fine, so I rebuilt this one in unreal and it also works not sure what I did to break it. I did relise that you don't need to pull in the orient in a scratch module you can directly set the particles to use the Houdini orient anyway.

Hi,

I am doing some RnD on exporting Houdini sims into unreal. I know there are several methods such as alembic and fbx, however I am testing exporting packed RBD sims to unreal using Niagara.
I have a RBD sim that is spawning different objects that grow over time and collide together. I am using the labs Niagara ROP to export the points as particles. I have meshid, pscale, Cd, P and orient, which I am exporting to unreal.

In Niagara I am importing the cache where I have been able to set the position, scale and color of the particles. I am using a scratch module to bring in the meshid and then I can copy the meshes which I exported seperately onto the points, this all works really nicely. The problem I am having is picking up the correct orientation. In the Niagara scratch module I am importing the orient attribute similar to the meshid and using it to set MeshOrientation. There is also a tickbox that says DoHoudiniToUnrealConversion which I have ticked on. It is changing the rotation but its not working correctly, maybe some axis are being flipped or I have missed another step, does anyone have any ideas thanks. I can post some example files if needed.