Line connecting peripheral points

Is there a node (or code) that would create a line connecting the peripheral points in an irregular cluster of points?

 

<span style=“line-height: 1.5em;”>Thanks.</span>

Regards,

Vikram Subbaiah

 

If all points are in the same plane (or on the same surface) you could use my Convex Hull 2D node. Haven’t tested it in 0.7.1 yet, though.

1 Like

Thanks for the suggestion Andreas.

However, it didn’t work as the Convex Hull node says the points are too orderly - “Singular Data Input(ie. Trying to triangulate data that contains a regular lattice of points. Introducing some noise to the data might resolve the issue)”

I’m trying to trace the irregular boundary of the regular lattice of points.

Regards,

Vikram Subbaiah

Sounds like you’re using the built-in Convex Hull 3D node. Try the Convex Hull 2D node from the package manager.

Currently it’s impossible to add images to posts on the forum, but have a look at this image - I think that’s what you’re looking for, right?

https://raw.githubusercontent.com/CAAD-RWTH/DynamoSamples/master/package_samples/Convex%20Hull%202D/ConvexHull2D_Result.png

 

1 Like

Andreas,

Tried the Convex Hull 2D package, but it doesn’t seem to work.

Thanks.

Regards,

Vikram Subbaiah

I’ll see if I can cook up a 0.7.1 compatible version.

There’s a 0.7.1 compatible version in the package manager now. Try that and let me know if it works for you.

1 Like

Andreas,

There aren’t any warnings or errors, but no geometry is being generated.

I’m working with a regular grid, with an irregular boundary. Convex Hull, Delauny and Vonoroi do not seem to work.

Thanks.

Regards,

Vikram Subbaiah

Could you post a file here?

1 Like

Andreas,

Unable to attach here.

However, below is one set of points, which when pasted in the code block and the output fed into work with …Convex Hull, Delauny, Vonoroi, Nurbs Surface, does not work.

Thanks for looking into this.

Regards,

Vikram Subbaiah

<span style=“text-decoration: underline;”>Code:</span>

{Point.ByCoordinates(-427.850,167.714,2.100),

Point.ByCoordinates(-427.850,172.910,2.100),

Point.ByCoordinates(-432.576,157.317,2.100),

Point.ByCoordinates(-432.576,162.514,2.100),

Point.ByCoordinates(-432.576,167.710,2.100),

Point.ByCoordinates(-432.576,172.906,2.100),

Point.ByCoordinates(-432.576,178.103,2.100),

Point.ByCoordinates(-437.301,146.921,2.100),

Point.ByCoordinates(-437.301,152.117,2.100),

Point.ByCoordinates(-437.301,157.314,2.100),

Point.ByCoordinates(-437.301,162.510,2.100),

Point.ByCoordinates(-437.301,167.706,2.100),

Point.ByCoordinates(-437.301,172.903,2.100),

Point.ByCoordinates(-437.301,178.099,2.100),

Point.ByCoordinates(-437.301,183.295,2.100),

Point.ByCoordinates(-442.027,141.721,2.100),

Point.ByCoordinates(-442.027,146.917,2.100),

Point.ByCoordinates(-442.027,152.114,2.100),

Point.ByCoordinates(-442.027,157.310,2.100),

Point.ByCoordinates(-442.027,162.506,2.100),

Point.ByCoordinates(-442.027,167.703,2.100),

Point.ByCoordinates(-442.027,172.899,2.100),

Point.ByCoordinates(-442.027,178.095,2.100),

Point.ByCoordinates(-446.752,141.717,2.100),

Point.ByCoordinates(-446.752,146.913,2.100),

Point.ByCoordinates(-446.752,152.110,2.100),

Point.ByCoordinates(-446.752,157.306,2.100),

Point.ByCoordinates(-446.752,162.502,2.100),

Point.ByCoordinates(-446.752,167.699,2.100),

Point.ByCoordinates(-451.478,141.713,2.100),

Point.ByCoordinates(-451.478,146.910,2.100),

Point.ByCoordinates(-451.478,152.106,2.100),

Point.ByCoordinates(-451.478,157.302,2.100),

Point.ByCoordinates(-456.203,141.710,2.100),

Point.ByCoordinates(-456.203,146.906,2.100),

Point.ByCoordinates(-460.929,136.510,2.100)};

This is really weird, Vikram. My sample file (https://github.com/CAAD-RWTH/DynamoSamples/tree/master/package_samples/Convex%20Hull%202D) works perfectly. But if I use a code block with (your) coordinates, Dynamo and Revit both crash. My suspicion is that the code block coordinates are to blame, but I’ll have to do some more testing.

1 Like

You are probably right.

Revit/Vasari also crashes any time I try to Import.ByGeometry a list of points.

Thanks.

Regards,

Vikram Subbaiah

Seems something has changed in 0.7.1, a slightly older daily build works fine. Please see the attached image.

ConvexHull

2 Likes

BTW, when I remove the unnecessary reference of LibGNet and other Revit specific modules from python node, it started working on 0.7.1 Attached is the updated definition file for Convex Hull 2D

If your python node doesn’t need to use Revit specific APIs then you can remove them from references so that your package works on stand alone dynamo as well.

1 Like

Sharad,

Would it be possible for you to provide the download link to the build that worked for you?

I didn’t manage to get the convex hull to work even with the .dyf you posted.

Thanks.

Regards,

Vikram Subbaiah

Sharad, of course, you’re right. The references were unnecessary. I have since updated the package and removed all references.

1 Like