What are the Performance-killer for VR(eg.OculusQuest2)? all postprocess, all screen-space?

Thanks for this expertise .

I’d like to add somes points and would love to have your feedback.

■ Drawcalls:
On Quest: not too much over 200 drawcalls & 400,000 triangles per frame
On Quest2: not too much over 250 drawcalls & 900.000 triangles per frame

■ Mobile multiview:
It is supposed to be desactivate for VR. But it must be enabled if you need to use a screencapture2D (in SceneColor capture source mode)

■ Forward shading/rendering:
It must be desactivated but beware that somes features become forbidden: DDX/DDY, WorldPositionBehindTranslucency , because of unreadable Scene Depth… (Can’t be packaged at the end.)

■ Mobile HDR:
It must be disabled. So no more PostProcess, but beware that you will not be able to use Decals too anymore.

■ Dynamic Foveaded Rendering must be activated.

■ Translucency:

  • Don’t use translucent big poly in front of the camera or cut off all the unnecessary space. Small translucent or additive material seems usable.
  • Do not mix transparent and opaque in the same mesh. (It renders twice?)

■ Lowpoly:
Flat shading multiply vertices in the engine compare to a smoothed lowpoly shading. In fact, everything different between each polys, splits vertices (UV islands, vertex weight, smoothing group…)

■ Do not use big or long unsubdivided polygon. (Or Do not use poly that are bigger than the tile chunk.)

■ PixelDensity command can be set to 0.85 to reduce the resolution an acceptable level.

■ About 1990 tips that helps for 2022 VR Dev:

  • Work in Unlit if you can.
  • Do not do heavy process on Event tick.
  • Avoid destroying, prefer pooling.
  • Audio must be 22khz and not too much as the same time.