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PxrDirt renders local geometric occlusion. This is useful for applying shading effects to nooks and crevices.

Note

A traditional ambient occlusion effect can be accomplished by setting the occluded color to black and unoccluded color to white.

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Controls the number of occlusion samples per camera hit point. More samples reduces can the noise at the cost of increased render time.

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFilternumsamples
gutterSize20
titleIntensity
animatefalse
captionstrue

Sample Distribution

Sample distribution can be uniform or cosine.

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Possible values are uniform and cosine (Lambertian).

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFilterdistribution
gutterSize20
titleIntensity
animatefalse
captionstrue

 Description
UniformRays are not weighted in any particular direction in the hemisphere above the shading point.
CosineCosine distribution is a commonly used to render ambient occlusion.

Cosine Spread

Sample spread of rays for when using cosine distribution. A value of f 1.0 gives a perfect Lambertian distribution.

Falloff

Falloff values greater than zero create a softer look. Values less than zero give a hard edge when combined with max distance.

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFiltercosinespread
gutterSize20
titleIntensity
animatefalse
captionstrue

Falloff

Falloff can be used to control the softness of the occlusion effect.

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFilterfalloff
gutterSize20
titleIntensity
animatefalse
captionstrue

Max Distance

The max distance at which objects may occlude. Zero is infinite (all objects occlude).

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFiltermaxdistance
gutterSize20
titleIntensity
animatefalse
captionstrue

Direction

Trace rays in the direction of the surface normal (outside), inverse to the normal (inside), or in both directions.

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFilterdirection
gutterSize20
titleIntensity
animatefalse
captionstrue

Bias Normal

Add a directional bias to the normal vector. Values must be specified in world space.

Carousel Image Slider
includepxrDome_intensity05.jpg, pxrDome_intensity10.jpg, pxrDome_intensity20.jpg
maxNumber3
dotsfalse
columns3
infinitefalse
sliderHeight190
arrowsfalse
labelsFilterbiasnormal
gutterSize20
titleIntensity
animatefalse
captionstrue