Geometry Classes#

Note

All Geometry classes are documented in this Google Spreadsheet.

../_images/geometry_classes_overview.png

Geometry classes are used to define the geometry and geometrical conditions of a given observation type.

  • Geometry classes can be of the following types/classes: Scalar, Vector, Multidimentional, all inheriting from the gfinder.geometry.Geometry class.

  • A Geometry object can be associated to a GeometryEvent object, which can be an instant acquisition (Measurement), an Observation, or a Sequence.

Searchable geometries

Only Scalar Geometry objects associated to a Measurement (measurement_geometries property in ODFs) are “searchable”, and can be used to define geometrical conditions. Exceptions: gfinder.geometry.No_Compensation_Required and gfinder.geometry.Scanning_Angle classes are not searchable.

These searchable Geometry objects should primarily be independent of the spacecraft pointing(eg: gfinder.geometry.SC_Altitude), but can also be pointing-dependent and used during planning activity when the SC pointing is frozen (eg: gfinder.geometry.Target_Point).

Pointing-dependent geometries

Pointing-dependent Geometry classes typically tell us where we are pointing at and what are the illumination conditions; using a given spacecraft pointing baseline (mission scenario), or using a simulated pointing (not yet implemented).

Direction geometries

“Direction-type” Geometry classes could be used to define simulated pointing (eg: gfinder.geometry.Limb_Point_Direction), telling us where to point at. See geometrical_models_computation.