Tie lines category
Tie lines category specifies what tie lines of type Section line following surface slopes are used for solving XY and Z mismatch. The settings mainly effect fluctuating XYZ solutions. Anyway, the values should be set in a reasonable way for a data set. The default values (XY when slope > 45 deg, Z when slope < 45 deg) are for mobile data sets where vertical walls are available for XY matching. It is recommended to change them to smaller values for airborne point cloud data, such as XY between 15 and 30 degree and Z accordingly. The steeper slopes there are in the data set (in the terrain and/or building roofs, potential places for searching Section tie lines), the larger the value for XY can be. A larger value for XY leads to a more reliable fluctuating XY solution for a data set.
Setting |
Effect |
---|---|
Xy when slope > |
Section lines are used to solve XY mismatch if the slope gradient is larger than the given degree value. |
Z when slope < |
Section lines are used to solve Z mismatch if the slope gradient is smaller than the given degree value. |