C3D-SURFACE DATA CLIP BOUNDARY

[CADEngr2014]

Hello,

I am using Civil 3D 2014.

I have a surface created from some C3D points, an outer breakline enclosing these points, and an outer boundary.  The outer boundary is the same as my breakline, I add it once as a breakline and again as an outer boundary.  I have other points outside the breakline, all part of the same point group as the above mentioned points.  The points outside the breakline are not visibly part of the surface since I have the outer boundary (breakline) applied but were initially part of the surface data.  If I use a data clip boundary type, instead of the outer boundary, I get a slightly different contour arrangement from my surface.  I am not convinced that the surface contours should be different since I have the breakline at the outer edge of my surface, so any triangulation to point data outside my surface boundary edge should be broken with the breakline,  Why would my surface contours be different by using the data clip instead of an exterior boundary? 

[Pointdump · Accepted solution]

C,

The difference is because you have other points outside the Outer Boundary. A Data Clip still uses those points, but an Outer Boundary does not.

Dave

[Pointdump]

C,

Here's something to try:

Use a Stepped Offset outside of your Breakline to use for the Data Clip. Put the Points outside the Outer Boundary into another Point Group which you can remove from the Surface Definition. I'm betting that then your Outer Boundary Definition and the Data Clip Definition will make similar-looking surfaces.

Dave