Wednesday, April 18, 2007

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.

1 comment:

dan said...

hey Angel, i have found the following to work:

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

the {General Segment Direction} was needed to correct an undefined property error.

also the formating must be set to "Direction"

works great but the expression formatting is reset to "Double" after a save, program close and then reopen. This results in labels not displaying the text correctly and returns an error when the expression is edited. Bug in C3d?

any word in a registered application id purger for 2007?