Operating system: Linux 5.4.10-arch1-1
Graphics card: GTX980Ti
Broken: 2.83 (01d9a2f71b56be9354ce31564e3dddb6af4a0757)
Short description of error
When using a 32 bit floating point normal map with Eevee, it looks as if Eevee resamples the image and reduces quality:
The same image and material used with Cycles seem to work fine. Also, slightly different setups in Eevee (e.g. manually generating (some of the) same data) do not produce the same issue.
More information in this video.
Exact steps for others to reproduce the error
- Load the above .blend file.
- Observe banding on the surface in Eevee material preview.
- Switch to render preview (Cycles): surface will become smooth.
- Try the other two materials and note that they do not exhibit the same problem in Eevee.
- Try baking normals using the ManualTangentNM material (see video for details). When baked with no range compression, Eevee does not seem to have an issue.