Slow Volume Rendering in Meta Quest 3

[alykhaled]

When I load a sample volume in meta quest 3 its very slow and there are many frame drops
Are there any way to downscale the volume or are there any recommended build settings to use ?

[mlavik1]

Hi!
You can change the settings as described here to automatically show a downscale promt when importing a dataset. That could help, but currently the downscaling is not very smart, so you'll get better results if you use Slicer 3D (or another tool) to downscale the dataset first (should be possible to import dataset, downscale and then export a new one).

Also:

• Make sure early ray termination is ENABLED
• Try reducing the "sampling rate multiplier":
  

I've also gotten great performance by enabling FidelityFX Super Resolution (in URP), though I'm not sure if that works on standalone Quest 3.

And by the way: The transfer function matters a lot. Transfer functions where the lower density values have zero alpha tend to be much faster (thanks to early ray termination).