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4 Geometry standards
implies that the arc is parallel to the reference circle. If this is not the case, then the
bearing must include altitude information.
Fig. 4.47. Operation startOfArc
endOfArc
The operation endOfArc calculates the bearing of the line from the center of the
eircle of whieh this are is a portion to the end point of the are. In the 2-dimensional
ease this will be an end angle. In the 3-dimensional ease, the normal bearing angle
implies that the are is parallel to the referenee eircle. If this is not the ease, then the
bearing must include altitude information.
Fig. 4.48. Operation endOfArc
upNormal
The operation "upNormal" returns a veetor perpendieular to the generie surfaee
(class GM _ GenerieSurfaee) at the DireetPosition passed, whieh must be on the generie surfaee.
Fig. 4.49. Operation upNormal