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To render the curve, we need to add at least a width attribute , curve interpolation and basisunless huge curves and hair are what you want. 

You can use the shelf button AddSpareParameters with the curve SOP selected to create the RenderMan tabs and the Geometry Tab for setting Curve properties:

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• Add a width attribute with Attribute Create.  Set a width value at the bottom, e.g. 0.01 and connect the nodes. It will automatically pick up the new value.

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• Map the width attribute to RenderMan attribute with Attribute Rename.

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• Connect the nodes.

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ROP Node settings

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