Hi,
There seems to be a bug when using either Bake to Texture or Render to Texture when baking a Complete map of a Standard or Physical Material with some Specularity/Glossiness and a bitmap applied as a bump map.
This is in 3ds max 2022. I've attached two max files (one for 2022 and one saved back to 2019) with a simple setup in case anyone wants to check if the bug is present in their version as well. It uses bitmaps from the standard Max map folder, but in case they have changed, simply use anything else. Bake with the camera as the active view as a reference for the highlight and adjust the output path as needed.
In my version, the resulting map has a specular with triangle artifacts as seen below:
This can't be fixed with smoothing groups or vertex normal editing.
Camera or type of light / light settings don't matter, either.
It doesn't happen in Arnold or V-Ray (with an equivalent setup).
It also doesn't happen with procedural textures or when using a normal map instead of a bump map. Using the bump map as an additional bump map in a normal bump map still results in the error.
Texture filtering doesn't seem to be the cause, either.
Workarounds I found so far:
Render in Arnold or Vray (Significantly slower, Additional time for recreating or adjusting materials needed)
Convert bump maps to normal maps (Requires an additional external step, minor loss of resolution).
Possible internal workaround: Have an OSL or other map that converts bump to a normal map on the fly.
Bake/project to a mesh duplicate (with a tiny push). This requires additional work, but when projecting, the bake comes out clean. It renders a tad slower, but seems to be the best solution so far, especially since I don't plan to update from 2022. I'll submit this as a bug report as well, though.
