Author Topic: Cross-sections vertises  (Read 24738 times)

vagk_18

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Cross-sections vertises
« on: December 09, 2014, 04:18:00 PM »
Hi, Lars.
I hope I find you well.
My question is about the cross-sections "produced" after loading two surfaces created by an another software and not cadtools.
I see the triangles and I took notes of the crossing points between the triangle legs and the cross-section lines. I find that cadtools
cross-section profiles include "extra vertices" in the 2dpolyline of the profile as if there are "extra" triangle legs. I saved the surfaces from the other
software and after I plotted them inside Autocad and the new cadtools triangles are the same. Could you explain the "extra vertices" at the cross-section profile?
I would like the cross-section profile to include only the crossing points that I see in the drawing. Is there an option to avoid all the extra vertices and keep only the vertices
sawn in the drawing?

Thanks again for your time.

Lars

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Re: Cross-sections vertises
« Reply #1 on: December 10, 2014, 07:42:10 AM »
Hi!
Booth cross section and surface profiles use a very simple method to display the surface line. For profiles the alignment is draped onto the surface and then plotted to AutoCAD. For cross sections the perpendicular line (based on user settings for Right and left) is draped onto the surface and then plotted to AutoCAD.

You can achieve same result by using a polyline with two vertices (start and end) and the drape it onto the surface using the commands in “Edit/View Surface”. So the result should be a vertex at every crossing with a triangle side (leg) if you do not use the option “Vertex only”.

To my knowledge there shouldn’t be any “Extra vertices”, anyway the result should be a accurate representation of the surface even if there is some extra points on the line.

vagk_18

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Re: Cross-sections vertises
« Reply #2 on: December 10, 2014, 08:29:49 AM »
Thank you for your reply.
Anyway I these "extra vertices" seems that is not a big problem. I think they are produced because the data saved from importing triangles from
an another software have "extra triangle legs", as if some triangles are broken to smaller triangles with almost the same result.
For better results I must draw a 3d polyline at every cross-section with vertices at every crossing point I see in the drawing (taking care not to make a mistake) and use the profile 3d option.

The real problem I noticed is that using after all the option cross-section area (cut-fill area between 2 polylines) the area calculated is not the same if you use the closed polyline area option.
The area with the closed polyline is correct.

I think you should check the calculation of the cut-fill option.
Thank you for your time.

Lars

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Re: Cross-sections vertises
« Reply #3 on: December 10, 2014, 05:15:21 PM »
If you have problems with the surface you might end up with a odd surface line (line goes back and forth on some segments). This might mess up the area calculation.

vagk_18

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Re: Cross-sections vertises
« Reply #4 on: December 11, 2014, 09:22:40 AM »
I 'm sending to you a sample to understand my problem