Previous fix flipped normal by both light AND view direction:
if (dot(N,L) < 0) N = -N;
if (dot(N,V) < 0) N = -N;
This double-flip broke spheres: when light is behind sphere, front faces
get N flipped by light (now facing away from camera), then flipped back
by view — but back faces get flipped once, causing inconsistency.
Correct approach: flip ONLY by view direction:
if (dot(N, V) < 0.0) N = -N;
This ensures the normal always faces the camera. Faces pointing away
from light naturally get NdotL=0 (no lighting) — correct behavior.
Spheres keep smooth normals, cubes get inward normals fixed.
emil28092005
6a473bdc53