Obtaining a digital model requires a prior process called triangulation. During this process, the surface is divided into a grid by a series of triangular planes which adapt to the relief and simulate the slope changes occurring on the terrain, which are defined by what are called break lines.
Triangulation can be done with different methods, the most usual of which is based on a scatter plot. A plane is generated with every three points. These triangles have a series of properties which allow a triangular irregular network (TIN) to be formed within the scatter plot that respects the shape of the terrain.
Triangulation can also be performed from contour lines. This method consists of discretizing each contour line and the subsequent triangulation of the points thus generated. Contour lines are considered as break lines.
Points with break lines
Resulting surface
In MDT, surfaces do not require the existence of surveying points. For instance, in order to create a surface from contour lines, it is sufficient to mark the relevant check box in the Create Surface command. Additionally, one can add, modify or delete vertices from surfaces using the commands included in the Surfaces > Utilities menu.
TcpMDT
