Does anisotropic filtering override bilinear and trilinear?

[halley]

See this earlier informative answer. In short, the UI to choose filtering options is a little bit misleading.

Anisotropic textures settings in Quality Settings

Neither, it’s using anisotropic filtering. Anisotropic isn’t some additional feature that can be used along side Bilinear or Trilinear, it’s the next filtering type after those two options. Unity’s texture options kind of hide that fact as you can’t choose “Anisotropic” in the same dropdown, but on the graphics API side there’s a setting for how to filter a texture during “minification” (when it’s being displayed smaller than the actual resolution), and the options are Point, Bilinear, Trilinea…

You should only be concerned with anisotropic filtering if you feel the camera will be nearly co-planar with an important texture for a significant period of time. The goal is to make the texture look better when one pixel of screen represents a long stretch of details across a texture.