Points to surface at revit Dynamo

[Sasa_94]

I have many points I want to create topographic surface or any kind of surfaces in order to get the perimeter shape , but i don’t know how to do it using Dynamo Nodes I tried Nurbsurface.Bypoints But It doesn’t accept the points

any solutions ??

[Ewan_Opie]

Try the Topography.ByPoints node.

For creating a Nurbs Surface your points would need to be sorted into groups, which could get tricky as they look quite irregular.

[Sasa_94]

@Ewan_Opie

Topography.ByPoints

Thank you it works…!
but is there any method or node to get the outline points of the shape only ?

[Ewan_Opie]

There is a ConvexHull.ByPoints node, but this only works with planar points.

To use this node to find your boundary points you will have to:

• Project your points onto the XY plane. (effectively removing any Z component)

• Find the boundary curve of the Hull of these points.

• Check for points thar occur on this boundary.

• Add the Z component back to the points based on their relationship with the original data.

Actually sounds like lots of fun just not at my PC at the moment to demonstrate.

Some topics to help.

Concave Hull

Concave Hull (Alpha Shape) from list of points with Python?

I cleaned up the code a bit: import clr clr.AddReference('ProtoGeometry') from Autodesk.DesignScript.Geometry import Line from math import sqrt, hypot points, alpha = IN OUT = [] pLen = len(points) alpha2 = alpha * alpha if pLen < 2: raise Exception('AlphaShape needs at least 2 points') for i, p in enumerate(points): for j in xrange(i+1, pLen): if p.IsAlmostEqualTo(points[j]): raise Exception('AlphaShape needs pairwise distinct points') dist = hypot(p.…

Convex Hull

Concave Hull (Alpha Shape) from list of points with Python?

Ha, @Mark.Ackerley, uni + work does leave for very little time, but I was intrigued. I know this has been answered, but here is another method that uses the Graham Scan method for “Gift Wrapping”. The best method is Chans algorithm from what I’ve read though as it is a combination of the Jarvis March and Graham Scan methods. Here is the Python Code ported over from Thomas Switzers GitHub (I take zero credit for this)… import clr clr.AddReference('ProtoGeometry') from Autodesk.DesignScript.Geo…

[Sasa_94]

Thanks a lot It’s done

[Dimitar_Venkov]

Whenever you want to use convex/concave hull on a set of points that are not in the xy plane, the simplest way to do so is to :

• use Plane.ByBestFitThroughPoints
• convert the resulting plane into a coordinate system
• transform the points from that coordinate system into the xy plane of the identity coordinate system
• perform the hull operation
• transform the result using the inverse transformation