I mentioned in the Interwoven Surface blogpost that my first idea was to use the Rhino command "Patch" and that this unfortunately was not awailable in Grasshopper. But now, Marc Hopperman has made a VBPatch so I thought I'd give it a try. So in this definition I start by creating some curves and then feed those into Marcs VBPatch. His VB-component will then bake those curves and run the Rhino Patch command and reference that surface back into Grasshopper. It is really amazing, if you change any parameters in the definition that will require the patch to be rebuild he also deletes the old surface. If you let the "AddPatch" boolean switch be on true while changing sliders you'll get an error message saying:"An object expired during a solution." To get rid of it check "do not show again".

This definition doesn't have the same restraints as the earlier one, so you might end up with strange results. patch.ghx