I had this question come up today which is a good one to review. The problem is the user was trying to create a Vertical Design Rule from a source location at the corner of a swimming pool where they had broken the sides of the pool into individual line segments. The Warning on the Vertical design states as follows
“Warning: A unique line ID could not be found because there are overlapping lines at the source point”
The issue in this case was caused by the two sides of the pool defined as individual lines, have a common point at the corner of the pool. If you then try to create a Vertical Design rule using the corner point as the source location you will get this error.
You could ask “why is this an issue when the two source lines are the same elevation at the corner”. That is a valid question. The answer however is that while they may be the same now, the software does not know that they will stay that way for ever. one line could change as more rules are created, and at that point this solution would fail.
So the options as shown in the video are as follows
- Edit the properties of the vertical rule that is flagging the error and pick one of the lines specifically as the source line for the vertical rule.
- Move the vertical rule just slightly so that the source point is attached to only one of the two lines at the corner - use Near Point Snap and turn off End Point snap while doing this so you can move it so that it is close to but not at the corner.
- Join the two lines together to make one line, first checking that other rules will not become invalid as a result.
The video below shows how to do all of these three things