RuneFox237
Issue:
Textures used in a material swap on particles seem to use an incorrect mipmap compared to textures used on the original material used by the particle system.
VRChat Avatar showcasing the bug:
https://vrchat.com/home/avatar/avtr_985cb361-cea2-4502-b406-72fe3b56acb1
The avatar contains a particle system that has toggles for 3 material swaps:
  • The Red material is the default material the particle system was uploaded with
  • The Blue material is the swap material and showcases the incorrect mipmap level
  • The Blue(NoMipMap) material is the same as the Blue material but using a duplicate of the blue texture where the 'generate mipmaps' toggle in the texture import settings was unchecked. This material does not have the same bug as above.
All textures used on materials for this particle system test were 512x512 and should look identical aside from color.
Additional Notes:
  • This seems to only apply to textures that are not in use on the avatar in it's initial state. i.e. adding an additional mesh/material to the avatar that is using the same texture used on the Blue material will result in the particle system using the correct mipmap level on the Blue swap.
Reproduction Steps:
  1. Create a particle system
  2. Create an animation that swaps the material of the particle system with a material that uses a separate texture.
  3. Activate the particle system, observe the normal texture
  4. Swap materials being used by the particle system, observe the lower resolution texture
Expected Behavior:
The expected behavior is that the textures used in the particle system look as high quality as they need to, i.e. using the correct mipmap level for the distance they are at from the camera.
Attachments Description:
Attached is a video showcasing the bug.
ParticleMipMapBug

ParticleMipMapBug