Simul Support ExchangeCategory: VRVR Optimizations
pftq asked 1 year ago

What should I look at to reduce frame impact of TrueSky in VR? I noticed that reducing cloudiness even to zero had no effect, so it seems to be something unrelated to how the rendering actually looks.  Same with decreasing resolution, removing depth blending, etc.  Only when toggling Truesky visibility off completely does the FPS change, so I’m wondering what exactly is taking up the overhead if not the rendering.

pftq replied 1 year ago

The more I dig into this, it seems like most the cost comes from objects the intersect with the clouds, especially landscapes. I had a test where there was literally just True Sky and a large simple-mesh landscape with mountains intersecting the clouds. Both do fine on their own, but if both are enabled at the same time, frame rate drops like a rock.

pftq replied 1 year ago

But actually straight up disabling depth blending doesn’t actually help, so that stumps me there.

2 Answers
Andrew Richards Staff answered 1 year ago

Could I ask which version of trueSKy you are using and whether you are using Unity, Unreal Engine or your own game engine?
The first thing that I would check is you are using multi-pass or single-pass instanced rendering.

Best Wishes,

pftq replied 1 year ago

Unreal Engine with TrueSky 4.1a
I have instanced stereo enabled.

pftq answered 1 year ago

Any update? How can I disable the computing cost of Truesky at runtime? Setting cloudiness to zero does not affect the resource cost of Truesky.