CONTAINSPOINTICRS

CONTAINSPOINTICRS is a geospatial predicate used to determine whether a geometry contains a given point, with explicit handling of coordinate reference systems (CRS). In line with standard topological predicates, it evaluates to true when the interior of the geometry strictly contains the point; a point on the boundary is considered outside the interior, and thus yields false.

The predicate is designed for use in environments where inputs may come in different projections. CONTAINSPOINTICRS typically performs a coordinate transformation so that both the geometry and the point share a common CRS before performing the containment test. This CRS-aware behavior helps ensure accurate results when integrating data from diverse sources.

Usage and syntax vary by software. A representative form is conceptually stated as CONTAINSPOINTICRS(geom, pt, geom_crs, pt_crs), returning a boolean. In practice, many spatial databases expose equivalent functionality through a CRS-aligned containment function (for example, by transforming one operand to the CRS of the other and then applying a standard containment test). Users often achieve the same result by explicitly reprojecting inputs and using a conventional contains predicate, such as ST_Contains, after alignment of SRIDs.

Implementation considerations include performance impacts from on-the-fly reprojection, handling of edge cases where the point lies on or near the boundary, and handling of degenerate geometries. Users should be aware of differences between geographic and projected coordinate systems, and the potential for numerical precision to affect borderline results.

See also: Contains, ST_Contains, SRID, Coordinate Reference System, Reprojection, DE-9IM.