Shiny surfaces
A splat stores a surface’s colour per viewing direction only as a smooth function, so it cannot hold sharp reflections. Mirrors, chrome and polished metal come out blotchy, their reflections broken into patches; glossy paint and plastic come out a little soft. Matte surfaces are what splats do best.
How much it matters
Section titled “How much it matters”Our test: a monkey on a checkered pedestal under an outdoor sky, one material at a time, trained at Draft and scored on 40 views training never saw.
| Material | Score |
|---|---|
| Matte (roughness 0.6) | 43.0 dB |
| Satin (roughness 0.3) | 41.3 dB |
| Glossy red plastic (roughness 0.05) | 35.5 dB |
| Polished gold (roughness 0.15) | 30.3 dB |
| Chrome mirror (roughness 0.02) | 27.6 dB |
When your subject has mirror-like metal or a clear coat and Min Roughness is 0, Create Splat’s Check Before Rendering names those materials, with Set Min Roughness to 0.3.
Min Roughness
Section titled “Min Roughness”Min Roughness (in the Rendering panel) renders the views with every glossy surface at least this rough. Your file stays as it is: only the background render changes. Reflections come out blurred, but clean.
- At 0.3, the splats matched their softened views 4 to 7 dB better than the sharp ones matched theirs.
- The glossy plastic even came out closer to the original (+0.3 dB).
- Gold and chrome lose their sharp reflections (−1.6 and −2.2 dB against the original), and their blotches with them.
- Glass keeps its roughness: rougher glass would hide what is behind it.
0.3 gives a clean satin look; 0 renders the materials as they are.
More views, splats and steps
Section titled “More views, splats and steps”Standard quality sharpens reflections the most: at Draft’s image size, Standard’s numbers of views, splats and steps gave the gold +3.0 dB and the chrome +2.1 dB. SH Degree 3, which objects use by default, holds sheen and soft reflections best; see Training settings.
Glass and fog
Section titled “Glass and fog”Glass, mirrors and fog train, but less well than solid surfaces. Expect them to look softer than in your renders.