To create a more detailed exterior based on any input building geometry, I procedurally generate multiple layers of pipes and cables. The foundation of this was based off of this video by Junichiro Horikawa.

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After base curves are generated, I use a Ray SOP with various constraints to build pipes close to the surface. For the cables, a pin group is created based on proximity to a part of the building's geometry. Then, using a mix of voxelized and unedited geometry from the input building as a collision, I apply a basic vellum solver to let the cables sit more naturally.