Existing Rhino Functionality to Rebuild Unstructured Quad Layouts from Polyline Surface Boundary Data

[Kenny (Kedrick Shepherd)]

Hi Pascal,

Thanks for the response. I’ll use another image to describe the problem:

Say I want to rebuild this trimmed annulus with the minimal number of surface spline patches supporting this configuration of extraordinary points. The rebuilt Brep will contain 6 surface patches and will look as above. I can use the following commands for the following labeled surfaces:

1. Brep.CreateEdgeSurface
2. Brep.CreateFromSweep
3. I cannot find an existing command that works – I have a closed loop closer to the center of the annulus and an open curve closer to the exterior.

Thus, each surface is well-defined except the surface labeled 3, where I cannot find a command that will yield the surface in the white space. As a result, I cannot seem to convert this trimmed surface into an untrimmed Brep.

I have looked at ways to open a closed curve (for the purpose of sweeping, for example), but this discussion seems to signal that this is impossible in Rhino.

Open a closed curve

Strange I can’t figure this one out: how do I open a closed curve? Basically I want to open a closed curve at its seam, while maintaining the exact same shape of the curve - split the seam point into 2. The open curve would have a starting point and an ending point in the exact same place. Further along these lines : how do I create an open curve, with the start point and the end point are in the same place? When I place my end point, Rhino automatically closes the curve. I suppose…

Do you have any recommendations on how to generate the surface labeled 3?

Thank you, as always, for your help.