As science matures, over-arching concepts emerge that simplify the subject. Such simplification fosters increased efficiency and practicality. Regarding spatial data, rules of solid geometry are long-standing and used in many applications. A consequence of the digital revolution is that procedures for working with flat-Earth spatial data need to be reconciled with higher-level geodetic applications of geospatial data. A simple model embodies flat-Earth assumptions while more rigorous mathematical expressions are needed to represent location with respect to the ellipsoidal Earth. The 3D global spatial data model (GSDM) is an over-arching concept which reconciles those perspectives by utilizing 3D space for computations. The GSDM is a practical solution which serves the needs of flat-Earth spatial data end users without sacrificing the rigor of geospatial data.
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