Optimize draw call

Hello, i have trying to optimize draw calls to my scene for gear vr, the problem is i don’t have so much polygons, (10k), all objets are static, i use just 6 different materials, but the draw calls grows up to 350 (100 recommended max by epic). i don’t now what to do again because i think i have optimized polygones to maximum low poly.

All object are static

The pawn actor is a little car very small in the road. Does the scene size have an influence on draw calls ? If i set the set scale from 5 to 1 for exemple and i reduce the pawn size to does it optimize draw calls ?
Have you an idea about other ways to optimize draw calls ?

Thanks !

More draw calls come from:

  • Using many different materials. Combining multiple textures into a single big texture usually helps a lot. But you have only six, so that’s not the case.
  • Translucent materials. Avoid them.
  • Lights casting dynamic shadows.
  • Unnecessary objects being rendered. This is an easy gain for corridor-based environments, urban exteriors. Precomputing visibility can help greatly. But it rather won’t be useful in your scene.
  • Dynamic objects (but you say all your objects are static).
  • Lots of separate objects that are not batched. This one is interesting. In Unity, static objects with the same materials and settings were automatically batched (combined) into a single draw call. After reading this discussion, I’m not sure if it’s done in Unreal too. Logically, it should be but is it? - Please support dynamic and static batching to minimize drawcalls for mobile and low-e - Feedback for Unreal Engine team - Unreal Engine Forums . One person suggests using “Editor Settings → Experimental → Actor Merging”. You can at least try joining some objects with the same material into a single mesh, before exporting from your 3D package.

Polygon count doesn’t influence draw calls number. Nor does object size, so don’t worry about it.

Oskar

Thanks Oskar, it really help me !

Just One more question, when i delete all objects in my scene and sky map (full black) i’m at 50 draws calls, when we now that gear vr don’t support more than 100 draw call i don’t understand :confused:

Thanks again

=> Actor merging seems to work perfectly, i come from 400 draw calls to 100