Fade billboard particles close to Camera in VR

I’ve been digging into documentation and this seems to be possible in Unreal engine but not Unity.

I am trying to fade billboards coming from an particle emmiter when they approach your face in VR, particles constantly attacking your face without this… how might one do this?

Shader that throttles the transparency when close to a certain Vector3?

developing for SteamVR / Vive

Using Unity 2017.1.1f

Standard Particle Shader scheduled for Unity 2017.3 has this function.

https://forum.unity.com/threads/feedback-standard-particle-shader-version-f4-20170710.482532/

I don’t think Unity has anything for this built-in, but there are two things you can try:

In the last section of the Particle System settings, it has a setting for maximum particle size. You can use that to force it to scale down as it approaches the player.

You can write a custom particle shader that adds forced transparency when the view depth is low enough.