Layers and groups have properties that control how they react to lights in a scene. When layer or group is selected, you can adjust these parameters in the Lighting section of the Properties Inspector. Groups have a single Shading parameter. Layers have Shading, Highlights, Shininess, and Diameter parameters.
Shading: A pop-up menu to set how an object responds to lights in the scene. If set to On, the object can be lit. If set to Off, the object ignores scene lights. If set to Inherited (the default), the object uses the Shading value of its parent.
Note: When a layer or group is nested in one or more parent groups, setting its Shading parameter to On overrides any Shading parameter settings applied to the parent groups.
Highlights: A checkbox to control whether lit objects show highlights. This parameter has no effect if Shading is set to Off. Click the disclosure triangle to reveal an additional Shininess parameter.
Shininess: A slider to set how strong an object’s highlights appear. Higher values create a glossier appearance. This Shininess parameter is disabled when the Highlights parameter is deselected.
Diameter: A slider that becomes available when Light Type is set to Directional, Point, or Spot. Diameter affects how lights are reflected as highlights in 3D Text objects.