Break-lines
The triangulation function in SIS Desktop will accept multiple geometry types (Points, LineStrings and Polygons) as input. Ensure all input geometries have a valid Z origin.
Where LineStrings or Polygon boundaries cross triangulation triangles a new vertex on the LineString will be interpolated along the LineString geometry which will act as a break-line in the triangulated surface.
Figure 1: A TIN created from 7 individual point geometries.
Figure 2: A TIN created from 7 individual point geometries and one LineString item string which acts as a break-line.