lwo smoothing groups support

[y2keeth]

would be cool but probably impossible

[themuffinator]

Good news: this already works. openQ4's LightWave loader reads both of LightWave's smoothing controls and builds vertex normals from them.

• Smoothing groups: SMGP polygon tags are read in lwGetPolygonTags and stored per polygon.
• Smoothing angle: each surface's SMAN value is read, for LWO2 and older LWOB files alike.
• Normals: lwGetVertNormals only blends a neighbouring face into a vertex normal when both faces share a smoothing group and fall within the surface's smoothing angle. The model converter keeps those normals and splits vertices along the hard edges.

A few things to keep in mind when authoring:

1. Turn smoothing on for the surface and give it a max smoothing angle above 0. A surface without SMAN renders faceted.
2. Each polygon belongs to one group, and groups match by equality. They aren't 3ds Max-style bitmasks.
3. Surfaces whose material has a renderbump line ignore the file's normals on purpose and are smoothed across the whole surface, so the shading matches the baked normal map. For a hard edge on one of those, split the geometry or give that part its own material.
4. Explicit custom normals aren't read. That's the NORM vertex map some LightWave 9+ and Modo exporters write. Normals always come from the smoothing rules above.

If a model doesn't shade the way it does in LightWave, please open an issue with the .lwo and its material and I'll take a look. Closing this idea as already supported.

[y2keeth]

oh ok