Canonical way to get normal during surface assembly

Question

Canonical way to get normal during surface assembly

szellmann opened this issue 9 years ago · comments

Provide a canonical way to obtain a surface (or vertex) normal when assembling surfaces. This would enable real user-defined geometry.

Stefan Zellmann · Answer 1 · Sun Oct 11 2015 03:57:35 GMT+0800 (China Standard Time)

Partially addressed by commit 21cc07a. Some primitives have precalculated normals, some don't. get_surface() should probably be adapted so that the following versions of the get_normal() customization point are valid:

get_normal(hit_rec, prim);
get_normal(normlas, hit_rec, Primitive{});
get_normal(normals, hit_rec, Primitive{}, NormalBinding{});

Similar considerations apply to get_tex_coord().

Stefan Zellmann · Answer 2 · Thu Feb 18 2016 23:25:59 GMT+0800 (China Standard Time)

63c20cf and address adf5861 this. I'm keeping the issue open because we should also get rid of the NormalBinding parameter in cases where this does not apply.

Stefan Zellmann · Answer 3 · Thu Feb 25 2016 17:22:00 GMT+0800 (China Standard Time)

Solved via cebec90

Interface is now:

get_normal(hit_rec, prim);
get_normal(normals, hit_rec, Primitive{}, NormalBinding{});

i.e. with precalculated normals around, specifying the normal binding is mandatory.