PxrDirt renders local geometric occlusion. This is usef= ul for applying shading effects to nooks and crevices.
A traditional ambient occlusion effect can be accomplished by setting th= e occluded color to black and unoccluded color to white.
Resulting colors for occluded and unoccluded shading.
=20 =20
Controls the number of occlusion samples per camera hit point. More samp= les reduces can the noise at the cost of increased render time.
=20 =20
Possible values are uniform and cosine (Lambertian).
=20 =20
Description | |
---|---|
Uniform | Rays are not weighted in any particular directio= n in the hemisphere above the shading point. |
Cosine | Cosine distribution is commonly used to render a= mbient occlusion. |
Sample spread of rays when using cosine distribution. A value o= f 1.0 gives a perfect Lambertian distribution.
=20 =20
Falloff can be used to control the softness of the occlusion effect.
=20 =20
The max distance at which objects may occlude. Zero is infinite (all obj= ects occlude).
=20 =20
Trace rays in the direction of the surface normal (outside), in= verse to the normal (inside), or in both directions.
=20 =20
Add a directional bias to the normal vector. Values must be specified in= world space.
=20 =20