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I'm having a very difficult time with import DWG/nurbs curves. It's something that i'm going to need to do a lot, so it would be great if anyone could help me with my issue: I need to be able to FIX NURBS curves so that i can use them in VWX.

in the first example i have two NURBS curves. One was imported, and the other was one i drew to finish the shape. I cannot, for the life of me, get them to form a solid shape. any idea?

in the second example, i have an imported moulding profile. it was a DWG. it came in as a NURBS curve. I cannot extrude it along a path. any ideas?

i've tried many permutations of Modify>Convert/Compose and Model>3D Power Pack, and i have read all i can on NURBS in VWX. i can't seem to find other examples of this specific issue where imported curves don't behave like curves drawn in VWX.

please help.

thanks

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After experimenting with your first file, I can suggest a couple of things to try -

- the two curves you are trying to combine are different degrees (look in the OIP, one is degree 2 and one is degree 3). They need to be the same degree to combine.

- once they are the same degree, you can combine them using Compose in the Modify menu.

- even when combined they don't want to create a surface. There is something about the geometry that is preventing it. If you choose Rebuild NURBS from the Model>3D Powerpack menu it is possible to correct, but some of the geometry smooths out. Try adding more points as part of the Rebuild.

What software is generating the original NURBS curves? Likely not Autocad based on past experience. There may be a better import format to use.

Kevin

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Edited by Kevin McAllister
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THANK YOU! I did not know about the Degree mismatch issue. That will solve many issues for me down the road.

I'm not 100% sure where these profiles come from. I know some are coming from an old mini cad file, and other's are unknown. one fix i've been able to make work is taking the old DWGs and going to Illustrator, then export to DXF and then import as 2D into VWX.

One more puzzle while i have your ear: i'm interested in WHY this is happening. Attached is a new file with base and crown moulding. One profile will work with both paths, and the other will only work with a simple shape. WHY?

I've found a work around already: my fix for the NURBS room shape is convert to lines>ungroup>compose>extrude.

Your knowledge is appreciated.

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OK. really confused how you got to a solid shape. i tried rebuilding after the compose, but i get no surface. Then i create surface from curves and get a shape with a fill but the fill isn't working. see pic. How did you get a surface?

i can convert the composed nurbs to lines and then compose that. but when i extrude i get a "solid" with no end caps. not as useful.

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Interesting, I can get both profiles and paths to work in VW 2013. I do have to flip the crown molding profile to get it oriented the right way. Perhaps VW2012 is having trouble because of the orientation. If you try and create self intersecting geometry the Extrude Along Path will fail.

I'd be cautious about using Convert to Lines in this process. It is creating a lot of extra points in the profiles (double click on the profile to edit it and you will see all the extra points) which will slow down the file a lot.

Do you know about the Extract Tool (Shift L)? It is a good way to get 2D shapes from 3D objects. Make sure that Create Planar Objects is checked in the tool's preferences to create 2D shapes.

I'm sure you also know that objects don't need to be NURBS curves to be used with Extrude Along Path. Your room shapes could just be polygons or polylines as can your molding profiles.

Kevin

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