Grasshopper
Clean Offset polysurface. Thickness
Hi guys, I get some doubts in relation with offset a polysurface in Rhino, i´m wondering how can we obtain a an clean offset performed on a polysurface, with the same result as if we use WB thickness based on distance diagonals, becouse due to the complexity of the shape the offset on a polysurface always seems collapse mainly if we work with sharp angles, and i already try many ways, however if we work with a mesh, the offset operation seems to works fine. - I use this shape as a sample, the shape i´m working in it´s more complex with many sharp angles folds. Thanks in Advance.
Mohamed Naeim
offset the curve (the sharp angular curve) and then extrude in the direction of the surface
Aug 21, 2016
Mohamed Naeim
Aug 21, 2016
Michael Pryor
It is quite easy if you just think about how a mesh does it. The key is to offset the corner points not the surfaces. Same as a mesh does with its vertices. Rhino offset doesn't work I assume because it offsets each surface to its normal then (messily) closes up the corners between. If you offset the corner points (and make sure they always stick together) you will have clean corners. This means you need the accumulative normal per each corner (normals at vertex). The idea can be the cross product of each corner points connecting edges ;) https://en.wikipedia.org/wiki/Cross_product
Aug 21, 2016