Filling in non planar surfaces

IS it possible to fill in non planar surfaces as if they were planar? eg. see attached
non planar.skp (12.5 KB)
I imagine it would be approximated by dividing the “surface” into a series of planes, similar to how sketchup approximates curves. But is there a way of doing it?

You may be speaking of “Softening” edges. It is done with the EraserTool (whilst holding the CTRL key,) or you can select a bunch of edges, and use the “Soft” checkbox in the EntityInfo dialog, … or use the “Soften/Smooth” item on the right-click mouse context menu.

BTW, once softened, they will appear as dotted lines if View > Hidden Geometry is checked. (otherwise they’ll be hidden.)

“It” is a technique called “hand-stitching,” whereby you reduce the surface to a network of triangles using the Line tool to make, essentially, a series of zig-zag lines that connect all the vertices. A surface constructed this way is faceted, like a gem stone or an insect’s eye. You can make the faceted surface appear smooth by using the soften/smooth command. In the sense used in SU, “soften” is to make the edges invisible, akin to hiding. However, this still leaves abrupt changes in shading crossing the boundary from one face to the next, like creases. The shading is smoothed across the boundary between faces using the “smooth” command, represented by a checkbox on the Soften dialog. This causes the entire network of triangular faces to appear as one smooth, continuous surface.


You could use the Curviloft plugin if you are dealing with complex shapes that you need to skin and not have to work out points to join to obtain a reasonably flowing surface.

Select your surface edges…

Select the Curviloft plugin Skinning option…

Apply. A solid will be created, and you may have to reverse the faces. This screenshot shown with hidden lines visible.

Hi , You cal also use the Soap skin and bubble plug in some cases to . Video here