lighting is not right


I render some quardric objects using gluCylinder, gluDisk(), etc. But it seems that all the faces reflect the same amount of light. Do you know why? I know I have to set normals for drawing polygons. But I am drawing quardric objects, not polygons. I also know that it can be caused if diffuse light is too weak while ambient light is too strong. But it is not my case. Please help. Thanks.


Have you enabled normal generation for the quadric object?