I've seen several posts on this board related to vertical faces, overhangs etc. The problem is that all of these are limited by the underlying problems with the Delaunay Triangulation algorithm, which Civil3d uses to build surfaces.
2d Delauney requires that there be a single direction for "down" so that the triangles can all be calculated in a common x,y plane. It also requires that no two points can have a common x,y at different elevations. When the software was originally created ten years ago 2d Delauney was probably the only viable option, but with improvements in computing power new possibilities are available.
3d Delauney algorithms can now be used to produce stuff like this. I don't know for sure, but I suspect that the point cloud functions we've already seen in the 2016 ACad platform are already using something similar. We need 3D surface triangulation in Civil3d in order to solve some of the other issues and requests here.
Steve
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