NURBS surface from points

Hi Peeps,

I am having trouble using the "surface from points" command.

I have a rectangular grid of points. I moved them up in the z direction. I want the moved points to make a surface.

I input the points in the 'P' input parameter in the Surface component.

What goes in the 'U' input?

I thought it was an integer, the number of points in one direction.

The component turns RED when I input the number of points (20). I have 380 grid points. They should be 20 in the U direction, 19 in the Y, and 1 in the Z.

What am I doing wrong? What goes in the U input? Please help!

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Permalink Reply by Michael Pryor on December 15, 2011 at 5:15pm

make it 21. U+1.

because you have 20 divisions in the U direction, but 21 points, because of the end points on the surface edge.

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Permalink Reply by Ivy Hume on December 15, 2011 at 5:19pm

20 is my U+1. Anyway, I tried 19, 20, and 21-- I tried everything and all I see is red. I'll try to upload it again. Do I need to include some sort of vector conversion?

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Permalink Reply by Chris Tietjen on December 15, 2011 at 5:44pm

Hi Ivy,

Flatten the point list at the surface input.

Chris

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Permalink Reply by Ivy Hume on December 16, 2011 at 10:20am

That worked, but now I have a flat plane. I would like my plane to conform to the grid points as they are set after I moved them. This is why "flattening" does not achieve the final product I'm looking for. I would like the surface to curve... How else can I manipulate the points of a nurbs surface?

thank you!

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Permalink Reply by Brian Harms on December 16, 2011 at 11:00am

You could interpolate a curve through each row of your grid of points and then loft the curves. The surface would then update as the points move.

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Permalink Reply by M NICK on February 21, 2012 at 10:34pm

Brian,

Could you please tell me how to make a NURBS curve through each row of a grid of points? or through a list of points?

Thanks

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Permalink Reply by Brian Harms on February 21, 2012 at 10:50pm

Sure, it would be easier if you could upload a file you are working with - just because I'm not sure exactly how you are generating your points.

In general it's just list management. You can do this a few different ways (using series + list items, sublists, path mappers...)

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Permalink Reply by M NICK on February 22, 2012 at 5:58pm

Brian,

I have for example a text files, like the file I uploaded, these are a series of numbers generated randomly, I want make a NURBS curve for each row.

Thanks for your help:)

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Permalink Reply by M NICK on February 22, 2012 at 6:24pm

This is a text file

Attachments:

points.txt, 1 KB

Permalink Reply by Chris Tietjen on December 16, 2011 at 11:21am

I thought you were just stuck on getting the surface to generate. Here it is with unique Z-vectors. If you need more help it would be good if you posted your definition. Guessing is the hard part.