Bump and reflection artifact spotted


The few past Blender releases have boasted some improved bump settings in the texture influence panel:

However, setting the Best Quality bump mapping for a material that gets reflected results in weird artifacts in the reflected image.

I was getting really upset not finding the source of the artifacts in the reflected wood panelling, then I tracked it to the bump settings:

The other options seem to work fine, I finally went for “original” mostly for the name than observing any real difference 🙂

(test done in Blender 2.58)

Update on January 04 2012 – Blender 2.61 (different scene) looks like only “original” bump method gets a clean reflection.. some times… Note: “original” inverts the bump (is that why it is called original??)


Categories : Materials, Rendering
  • morten mikkelsen

    The issue has been addressed before. Have you seen this bug report?

    Unfortunately it was never fixed. It’s not the bump mapping method that is failing. Blender’s renderer is failing to compute derivatives during reflections. Original Bump masks the problem (unintentionally) because it fades the bump off too rapidly by distance.

  • Oana

    Thanks for the info! So it is a larger issue but I just bumped on the bump one 🙂
    Maybe it gets fixed in 2.6, I’ll have to remember to check this…

  • morten mikkelsen

    Thought you might want to see that you’re not the first to notice btw 🙂

  • Oana

    I see. So it’s not solved yoe, isn’t it? I just installed 2.6 and didn’t get to test that yet. (still trying to spot the new features!)