The bent normal map describes the average direction of ambient lighting. The Bent Normals from mesh baker is derived from the Ambient Occlusion from mesh baker.
Secondary Rays: amount of secondary rays (the higher will produce less noise)
Min Occluder Distance: minimum distance where the secondary rays will hit the high poly geometry
Max Occluder Distance: maximum distance where the secondary rays will hit the high poly geometry
Relative to Bounding Box:
- off: units used in "Max Frontal Distance" et "Max Rear Distance" are the ones defined when exporting your mesh (m, cm or whatever you did set up in your scene export)
- on: units are relative to the bounding box of the object, 1.0 being the diagonal length of the bounding box
Spread Angle: maximum spread angle of occlusion rays.
Distribution: angular distribution of occlusion rays.
Ignore Backface: defines if the rays should ignore hits on a backface (if the high poly normal faces the opposite direction as the low poly from where the ray is fired). You should want this option activated most of the time.
Map Type: defines the type of the output map (World space / tangent space)
Normal Orientation: if the map type is Tangent space, defines if the map is encoded as DirectX or OpenGL