Sunday, March 05, 2006

Igor's GI tips

Igor has post a GI tips on this CGtalk thred


1. Use "Show Samples" diagnostics, let GI shows where are problems

2. Start from maximal simple settings:

- GI: 1 bound, Secondary Rays = 0, Sampling 8x8
- single Light with buffer shadow
- no AA

3. Increase AA (step by step) and see results with "Show Samples". Check geometry in areas are filled with red color. Things like leaves, grass, polygons hairs etc. are heavy for GI always and anywhere cause their geometry is "scattered" that makes GI interpolation technique ineffective. Maybe it makes a sense to exclude such groups from GI calculation

4. Replace buffer shadow with soft ray-trace shadow (not a big speed happy itself). We agree with Ian: GI + dome is a possible but imho not a lucky combo. Adding a light with GI Mode = Exclusive (no shadow) often is much better and faster if you need rid of dark areas

Thanks Igor