To render displacement on your geometry in RenderMan for Blender, use the PxrDisplace node.
Adding PxrDisplace
To add PxrDisplace, make sure you've already added a RenderMan material to your geometry. In the material properties 
, under the Displacement panel, select PxrDisplace from dropdown list next to "Displacement".
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- For transform related functions use the PxrDispTransform pattern.
- For displacement layering, use either PxrDispScalarLayer and PxrDispVectorLayer pattern.
Avoiding cracks on polygonal meshes
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