Advanced spatial topics

The software supports flat-Earth and round-Earth representations.

Snap-to-grid is the action of positioning the points in a geometry so they align with intersection points on a grid.

Interpolation is the process of using known points in a geometry to approximate unknown points.

The database server interprets polygons by looking at the orientation of the constituent rings. As one travels a ring in the order of the defined points, the inside of the polygon is on the left side of the ring.

Knowing the boundary of a geometry helps when comparing to another geometry to determine how the two geometries are related.

There are two methods you can use to test whether a geometry is equal to another geometry: ST_Equals, and ST_OrderingEquals.

Relationships between geometries relates to their location to each other.

In addition to having distinct properties of its own, each of the geometry subtypes dimensional properties from the ST_Geometry supertype.