Lofting Splines to get Surface

1st I was trying to create closed loop splines in revit but appears that it isn’t possible. So I created them in AutoCAD, linked it into Revit and tried to loft them to create one surface, it also failed. Now I am trying to select those splines with dynamo and see if it can loft it. Any suggestions are appreciated.
Contours - Splines.dwg (64.1 KB)
Lofting AutoCad Splines.rfa (428 KB)

The lofting also fails in AutoCAD, and I am trying to split up the contours to get surfaces, but no luck so far

Maybe start by creating a Revit Topography …



contours.rvt (2.0 MB)
The family with the contours was altered and imported into a Revit project

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What I am trying to model is this physical model. I tool series photos all around it and used autodesk Recap to create point cloud file and then linked it into revit and not trying to model surface

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You can convert the topography to a Polysurface

//Topography to PolySurface
tm1=topo.Mesh;
vp1=tm1.VertexPositions;
iG=tm1.FaceIndices;
lst1=List.Transpose([iG.A,iG.B,iG.C]);
lst2=List.GetItemAtIndex(vp1,lst1);
srf1=Surface.ByPerimeterPoints(lst2);
srf2=PolySurface.ByJoinedSurfaces(srf1);
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This is interesting, I’ll definitely try it. Thanks Vikram!

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A Nurbs Surface …


contours.dyn (43.0 KB)

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Were the lines still splines when you brought them from AutoCAD into Revit?
or were they exploded into little model lines?
Is there a way to keep cad splines in Revit and select them with Dynamo?
I am able to link AutoCAD file into Revit, but can’t seem to select lines with Dynamo when it’s a link.

I didn’t use the Autocad file, only exploded the object in the Revit family you’d provided.
Then raised the curves to their respective levels. (You should be able to get that modified family from the file at this post)

You might want to consider extracting the geometry information (Start and End Point) from Autocad into a csv file and build geometry from that.

Just looked at that Revit family and lofted 1st 3 lines and it gives these multiple surfaces almost like a mesh. What I am trying to do is have one seamless surface lofted from splines that I quickly made in that same family.

If it’s the bottom 3 curves, you can create splines by extracting points from the fragmented lines


splineSrf.dyn (22.7 KB)

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Vikram’s way works great, but I just realized that I need to adjust the contours to get that fabric-like look.
I made these contoured splines that can be easily modified in revit, but the problem is that they can’t be closed loops in Revit. Can they be closed in Dynamo and lofted after?

Pavilion - Single Cone.rvt (1.9 MB)
Splines Loft.dyn (21.9 KB)

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I followed Vikram_Subbaiah’s logic and I think I got it, but I am sure it can be done more efficient.

You could select all curves at once


Splines Loft.dyn (17.9 KB)

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