Force North Bearing

Many Civil 3D users have requested the ability to "Force North" bearings on line labels in the product for quite a awhile. As it turns out, althought there is no setting to do this exactly we can accomplish this with the use of an expression. I discussed this with a few Autodesk personel and Peter Funk, Autodesk Product Manager, put me on the right track by saying "...this should be do-able with an expression". Well, he was right the following expression, when applied in a Parcel Line Label style will accomplish just that. I created a Parcel Line Label Expression called "North Only" and defined it as...

IF(({Segment Direction} > pi/2) * ({Segment Direction} < (3*pi/2)),{Segment Direction} - pi, {Segment Direction})

Basically, this will subtract 180 degrees from lines in the second and third quadrants.

For some reason, my image capture will not upload at the moment, but this does work. Give it a try.

Civil 3D 2007 - Expressions

Here is how we will be able to create labels with mathematical expression in Civil 3D 2007.

Step 1 - We need to name and then define the expression in the appropriate collection of the "Settings" tab (ie. for Points, FL=Elev-0.5).

Step 2 - We will then use the newly created "Named" expression as a property that can be added in the "Text Component Editor - ..." dialog box accessed from within the "Contents..." of the "Label Style Composer - ..."