In Rhino8 shadows do not cast onto polysurfaces when: (1) there is a clipping plane, (2) the display mode shadows ignore clipping planes, (3) the clipping plane shows fills, and (4) the polysurface intersects the clipping plane. This may seem like a small detail, but it affects the critical functionality for architectural renderings and sun studies. This bug is not present in Rhino7 (possibly because “show fills” was added in Rhino8).
In the screenshots below the blue objects are surfaces and the purple ones are polysurfaces. When clipping is enabled shadows are not cast onto the purple polysurfaces when they intersect the clipping plane.
Display Mode: Rendered with shadows on and “Shadows ignore user defined clipping planes” enabled.
Release: Rhino 8 SR15 2025-1-19 (Rhino 8, 8.15.25019.13001, Git hash:master @ 74164bdf5469c2f269746857c54b8c44b74c7b24)
