Function normalizeStoreNormals

js/subdivision.js:443–454

(verts)

  }

  normalizeStoreNormals(verts);
  return { verts, indices };
}

// Normalise accumulated normal sums in place (shared by both indexers).
function normalizeStoreNormals(verts) {
  const nrm = verts.nrm;
  for (let i = 0; i < verts.count; i++) {
    const nx = nrm[i * 3];
    const ny = nrm[i * 3 + 1];
    const nz = nrm[i * 3 + 2];
    const len = Math.sqrt(nx * nx + ny * ny + nz * nz) || 1;
    nrm[i * 3]     = nx / len;
    nrm[i * 3 + 1] = ny / len;
    nrm[i * 3 + 2] = nz / len;