Rickymaveety I do not know the science or math behind it.   I just know that it works.  I could never get a cyl imported from Rhino to tile the procedural textures right until I mapped it that way in UV Mapper, then Bryce tiled the top and bottom along with the sides correctly.  Sometimes you can just map something with box mapping.  You do not have to export, or use the maps because we are talking about using Bryce Procedural Textures here not texture maps.   The act of uv mapping seems to tell Bryce how to apply the tiling.   Parametric mapping is what you want to apply in the material lab.

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