Notes
1. Creating TIN - Triangulated
Irregular Network
The sketch should be prepared for the correct creation of
triangulated network.
That means: removal of all points, which negatively affect the
elevation course, adjustment of breaklines so they would not cross
or overlap each other. The program tries to notice and fix all
these encounters. However, it is forced to remove few edges from
the process sometimes.
If the sketch contains islets (holes), it's advised to draw their
circumferences with 3D curve in an individual layer.
As an input set of points, following are usable: coordinates from
file, or coordinates of objects (POINT type or BLOCK type).
Accuracy of these coordinates is reduced to three decimal places,
for better manipulation with breaklines, which also participate in
triangulation with their coords. It is possible to use
triangulation only with breaklines, without a set of points.
2. Creation of
contours.
Algorithm for smoothing out TIN is sensitive to arrangement of
input set of points.
TIN should have its triangles, as similar to equilateral ones as
possible, which is sadly very unlikely. Introduction of breaklines
makes the situation even worse, because of frequent creation of
obtuse triangles, which contribute to serratedness during the
creation of contours. It's also advised to be careful, and not to
forget set sharp breakline, because forgetting it might cause
the overcrossing of contour.
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