tsc_TiltedGnssObservation

This an abstract subclass of tsc_GnssObservation, and contains a tilted GNSS coordinate.  The type of the coordinate depends on the base class and should be appropriate for the GNSS survey type (Store fixed positions or Store vectors from base).  Note that in all cases this coordinate represents the APC coordinate on a tilted pole and this coordinate cannot be used directly without reducing it to ground first using the tilt data.

Such an observation can be appended to the database only while the survey that observed the coordinate is still running.

Coordinate precision and pole tilt data must be captured at measurement time and supplied to this object, see tsc_GnssPrecisions and tsc_GnssTilt for more information.

Additionally each observation requires environment information - the survey and the antenna - which are supplied by the tsc_GnssEnvironment class.  An instance of tsc_GnssEnvironment should be passed in when setting the coordinate on the tsc_GnssObservation subclass to ensure the correct environment information is stored with the point.