Cull.ml1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22(* Claude Code * * Copyright (C) 2026 Yoann Padioleau * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public License * (LGPL) as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. *) (* See Cull.mli *) let faces_camera ~(eye : Vec3.t) (points : Vec3.t list) : bool = (* claude: this winding-based normal is ONLY for backface culling (an * independent, whole-face notion of "which way does this face * point") -- it is unrelated to the per-vertex normals used for * shading (see Shading). For a flat face these two normals happen to * have the same value; for a smooth one (e.g. a sphere's) they don't, * since each of its points has its own, different normal. *) let normal = Vec3.face_normal points in let centroid = Vec3.centroid points in Vec3.dot normal (Vec3.sub eye centroid) > 0.