The Plan Calculation group provides several methods to determine where the position of the new points will be created. The fields in the Parameters group will change depending of the option selected.
At Chainages - Points are created at regular chainage intervals with a given start chainage, which is defined in the Start Chainage field. If the first point on the indicated feature has a chainage dimension, CHN, the dimension value will be placed into this field. The Chainage Interval field defines the frequency of points along the feature. Both methods of height calculation are available.
Maximum Distance - Points are created on each segment to ensure that a maximum length of each segment does not exceed a specified value. The value in the Maximum Distance field is used. New points are inserted where the segment length exceeds this value. If we take an example where there is a segment length of 9m and a maximum distance of 5m, a new point will be inserted at the midpoint of the segment, 4.5m along. Both methods of height calculation are available.
Distance Along - Creates a single point at a user-defined distance along the feature from the start point. The Distance Along field defines this value and both methods of height calculation are available.
DTM Facet Edges - Creates points wherever the feature intersects with a DTM triangle side. The height of points is always calculated from the DTM triangles. The DTM that is used is that specified in the Reference DTM combo box.
DTM Intersection - Creates points where the feature passes through a DTM. The height of points is always calculated from the DTM intersection point. The DTM that is used is that specified in the Reference DTM combo box.
Datum Intersection - Creates points along the feature where the feature passes through a given datum, specified in the Datum Height field. The height options are disabled as the height is already the datum value.
Height Intervals - Creates points at the intersection of the feature string and regular height intervals or contours. The Height Interval field defines this value. The height options are disabled as the height is already calculated.
Number of Segments - Creates points so that each segment of the feature is split into a number of smaller segments, defined in the Number of Segments field. The height options are disabled as the height for each point is always calculated by linear interpolation.