Type Alias VerticalDatum

Vertical datum a georeferenced dataset is placed against:

• 'basemap' — drape the measured ground onto the flat map (z=0) or onto 3D terrain under the anchor.
• 'ellipsoid' — place the ground at its true WGS84 ellipsoid height (absolute, terrain-independent).
• 'orthometric' — place the ground at mean sea level = ellipsoid − geoid (absolute, needs a geoidN).