Folks,I know how to make normals from terrain in flat form. However, I want to learn how to make normals in spherical form from terrain. I tried to make normals but it resulted so funny. Shadows looks shining from south instead of from sun.dy = radius * pi/(nlat*grid);dz = radius * pi2*cos(lat) / (nlng * grid);dydz = dy*dz;nml = glm::dvec3(2.0*dydz, dz*escale*(elev[en-ELEV_STRIDE]-elev[en+ELEV_STRIDE]), dy*escale*(elev[en-1]-