Breaklines are lines or polylines that are used in surface modeling to represent a feature such as a ridge, stream or curb. Breaklines force triangulation and interpolation to occur between the vertices of the breakline, which prevents any other triangulation line from crossing the breakline. It is important to avoid crossing breaklines in the surface model because the program cannot force triangulation along both since holding one will cross the other. Also the program cannot hold the interpolation along both because the elevation at the intersection point can be different for the two breaklines. For example, consider a breakline going from 101 to 105 and another going from 107 to 109. If these lines had an intersection at the midpoint, the elevation for one would be 103 and the other 108. This is an error that needs to be fixed by the user because those two breaklines are holding different elevations at the same point.
This command checks for intersections between the selected breaklines and then identifies any crossing breaklines by highlighting them. You can then edit these crossing breaklines before doing surface modeling such as Make 3D Grid or Triangulate & Contour.
Ignore zero elevations (<Yes>/No)?
press Enter
Select surface entities to check.
Select objects: select polylines and lines
Finding points on breaklines.
2 crossing breaklines are highlighted
or
Found no crossing breaklines
Pulldown Menu Location: 3D Data
Keyboard Command: xbar
Prerequisite: Polylines
File Names: \lsp\makegrid.arx