Hello, all ! I have a real strange problem. In two words : I''ve created a simple scene (just a square) and then placed lights above the corners of that square. Lighting is enabled, scene with this four lights and one square is correct. Then I tried to put a cylinder (quadric) in the center of the square. The cylinder appeared, but two of my lights failed. The light in two corners was still correct, two other corners fell in the dark. Lights are high enough :-) What''s the possible matter ? I''m absolutely surprised because the scene without quadrics was correct (even more complicated scenes), but quadric breaks everything. Thanks !