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cdsuggs
2008-10-10, 06:33 PM
Most of the surveys we get here are flat CAD drawings with no contours, only points with text calling out the elevation. These drawings typically come through the client and we are unable to reach the surveyor to request contours or a point file.

The process of overlaying such a drawing into Revit, then manually entering each point to recreate the surface is a major drag. There has to be a better way! :???:

The simplest solution I've come up with so far would be to use Land Desktop or Civil 3D to create a surface from the points, then export the surface as contours for Revit. Problem... the price tag does not warrant the one tool we'd actually use.

Questions:
Have you encountered this issue? If so, how are you dealing with it?
Know of a plug-in to AutoCAD that translates points into polylines/contours?
Know of any slick lisp routines that could perform a similar task?

vicme0
2008-10-11, 06:18 PM
You don't need contours, only points in 3d space. Revit will create a surface with the given points and will create the contours for you.
If your points are in a flat 2d space with text calling out the elevation, and each of this text objects are placed (it's origin) just on the point or very close, you can script something that will create new points in 3d space using the x and y values of the text object's origin and using the text object's content as the z value. I have done a script for this but for Rhino 3D (another CAD software). I'm sure there's an easy way to script it in autocad too, but I've never scripted in it.

Joef
2008-10-11, 06:41 PM
A quick search of the Cadalyst magazine web site returned this lisp routine:

Creating 3d points:

Creating 3D Points
Pedro Ferreira sent a tip for Creating 3D Points at the Location of Selected Text Objects (Tip #2047). This utility is a simple LISP module containing the function PMSFPTWTXT. The function will ask you to select text objects containing the elevation value. That is, you create text objects where the value of the text is the elevation (z value) you want to use. The text may be the result of another custom application that reads data. The text is extracted from each text object in the selection set and used to formulate the z value of a point. The x and y values are obtained from the text object itself. The resulting point is placed in 3D on a layer with the same name as the command PMSFPTWTXT. This tip is a great seed module that you can modify to make use of z values in text that need some conversion before use. Thanks, Pedro!

I haven't tried it but it looks promising.