For my work, I’m making a large scene to visualize the area we are working on. All of the houses are made in Revit and imported to Unreal with Datasmith. I have coverted all the geometries to Nanite but am experiencing a pretty large performance drop still.
To my understanding, Unreal should easily be able to handle these models as they are far less complex than for instance the Megascans assets. And those can be copied over thousands of times in the same scene without issues.
Does anyone have some pointers for me that I can look at, or has the same issues from Revit → UE?
I work with vehicle models and just wanted to let you know I’m having the same issue. I’m importing a complex .stp model in datasmith and end up with around 18 million triangles in my scene. The framerate is at around 10fps.
If I import fbx files though and get to a similar geometry count the framerate in the same scene is around 70fps.
Looks like someone was dealing with a similar issue years ago: DataSmith import issues
The last bullet of the first post seems to be a similar issue.
I’m going to try putting all the datasmith geometry into a blueprint and see if that makes any impact, but I don’t have many ideas. In my experience, if you try to export datasmith geometry as fbx it will just crash Unreal, so that’s not an option either. The solution might just be to not use datasmith sadly.
There should not be a performance impact because it comes from Datasmith. At the end of the day, whatever way your asset came into the scene, the engine is managing meshes with material slots and lighting configuration.
Many things can impact the frame rates:
draw calls: how many distinct meshes are used by actors (are you using instancing as much as possible), how many materials and material slot per meshes.
number of triangles: are you LoDing or using nanite.
complexity of materials, lighting and graphical effects you set up in your scene
etc.
We would need more details on how your scenes are built.