Sets the contrast of ambient occlusion that Unity applies to indirect lighting in lightmaps. (Editor only).
Ambient occlusion (AO) is an effect that approximates how much ambient light a given point on a surface receives. When you apply AO to a Scene, areas of concavity - such as creases, holes and adjacent surfaces - appear darker.
This property determines how much indirect lighting - such as bounced light and skylight - contributes to ambient occlusion calculations.
The range is 0 through 10. The default value is 0. Higher values result in occluded areas becoming increasingly darker.
This setting affects lightmaps generated by the Baked Global Illumination system. Note that this property relates only to baked AO, and has no effect on any real-time AO post-processing effects.
When Unity serializes this LightingSettings object as a Lighting Settings Asset, this property corresponds to the Indirect Contribution property in the Lighting Settings Asset Inspector.
Additional resources: Lighting Settings Asset, aoExponentDirect<.