-- Name --<br/>breakline<br/><br/>-- Definition --<br/>A line of a critical nature which describes the shape of an elevation surface and indicates a discontinuity in the slope of the surface (i.e. an abrupt change in gradient). Triangles included within a TIN model must never cross it.<br/><br/>-- Description --<br/>SOURCE Adapted from [ISO 19107:2003].<br/><br/>EXAMPLE <br/>Breaklines represent local ridges or depressions (streams or drainage lines) in the surface, man-made structures (e.g. roads), etc. <br/><br/>NOTE 1  A breakline connects points with different elevation and therefore its description using 2.5-D coordinates (using the 'geometry' attribute) is fully recommended.<br/><br/>NOTE 2  No triangle in a TIN may cross a breakline (in other words, breakline segments are enforced as triangle edges), even if doing so violates the triangulation criterion.<br/><br/>NOTE 3  All breaklines are located on the ground surface or on any of the artificial structures built on it. <br/><br/>NOTE 4  Breaklines are useful as input data for the generation of a more appropriate or accurate digital elevation model by using interpolation methods.<br/><br/>