This lets you find the boundary of a set of points. FlashMNT will ask to select the points then will compute the convex boundary (a 3D polyline). You can then refine this boundary by giving a maximum segment length. The program will then try to find a boundary fulfilling this constraint. If a segment cannot be modified to fulfill this constraint, the program will stop. The option 'Ignore long segments if necessary' will let you continue even if a segment cannot be modified to fulfill the length constraint. FlashMNT will then show on the command line the number of not modified segments. Warning, in this case some points may be outside the boundary.

Once the boundary found, you can use it as a DTM limit.

Remark : if there is a big number of points, this command can be relatively slow.

Convex boundary

Boundary with length = 20