Extract Drain-Sewer

This option will form a section from the selected string. The section can then be edited using Section View option.

String
Select the required string with the mouse.

Start Chainage
Enter the required start chainage.

There are two major ways to form the string

1. Copy Close Points onto Longsection
Points near the string are copied and inserted into the string. This option is useful if you have taken stadia observations along the road or sewer, they will be used to form the string line points.

Distance Tolerance - This is the search distance from the string that is used to select points to copy onto the string.

Point Tolerance - When a point is selected and it is near an existing point, it is generally better to keep the existing point, this is the 'tolerance' distance used to detect this situation.

2. Interpolate Points using Triangles
Points will be computed at even chainages along the string and will have their height values interpolated using the triangle mesh.

Interpolate Even Chainages
Tick the box to compute points on the string at even chainages.
Chainage Increment
This is the 'even chainage' increment which will be used when computing the points.

Min Point Separation
Where a computed point is near an existing point, it is usually best to adopt the existing road point. This is the minimum 'tolerance' distance to be used when checking if there is an existing close road point.

All changes of Grade
Tick this box to insert points in the section/string at every change of grade, that is every triangle boundary.