Package org.apache.sis.geometry

Basic geometric objects (envelopes and direct positions).

See: Description

Class Summary

Class	Description
AbstractDirectPosition	Base class for DirectPosition implementations.
AbstractEnvelope	Base class for Envelope implementations.
DirectPosition1D	A one-dimensional position within some coordinate reference system.
DirectPosition2D	A two-dimensional position on top of Point2D.
Envelope2D	A two-dimensional envelope on top of Rectangle2D.
Envelopes	Transforms envelopes to new Coordinate Reference Systems, and miscellaneous utilities.
GeneralDirectPosition	A mutable DirectPosition (the coordinates of a position) of arbitrary dimension.
GeneralEnvelope	A mutable Envelope (a minimum bounding box or rectangle) of arbitrary dimension.
ImmutableEnvelope	An immutable Envelope (a minimum bounding box or rectangle) of arbitrary dimension.

Exception Summary

Exception	Description
MismatchedReferenceSystemException	Indicates that an object cannot be constructed because of a mismatch in the reference systems of geometric components.
UnmodifiableGeometryException	Indicates that an operation is not allowed on a geometry object because it is unmodifiable.

Package org.apache.sis.geometry Description

Basic geometric objects (envelopes and direct positions). Every geometry objects are associated with a Coordinate Reference System, which may have an arbitrary number of dimensions. However a few specialized classes restrict the CRS to a fixed number of dimensions only. The table below summarizes the most common objects, and list the Java2D classes that are conceptually equivalent.

Java2D and geometry equivalences

Purpose	Any dimension	One dimension	Two dimensions	Java2D equivalence
A point in a multi-dimensional space	GeneralDirectPosition	DirectPosition1D	DirectPosition2D	Point2D
A box in a multi-dimensional space	GeneralEnvelope		Envelope2D	Rectangle2D

Envelopes spanning the anti-meridian of a Geographic CRS

The Web Coverage Service (WCS) 1.1 specification uses an extended interpretation of the bounding box definition. In a WCS 1.1 data structure, the lower corner defines the edges region in the directions of decreasing coordinate values in the envelope CRS, while the upper corner defines the edges region in the directions of increasing coordinate values. Those lower and upper corners are usually the algebraic minimum and maximum coordinates respectively, but not always. For example, an envelope crossing the anti-meridian could have a lower corner longitude greater than the upper corner longitude, like the red box below (the green box is the usual case): In SIS, every envelopes defined in this package support the extended bounding box interpretation: for any dimension, ordinate values such that upper < lower are handled in a special way. This handling is slightly different for two groups of methods:

• In calculation of envelopes spans and median positions (centers) — handled specially only on axes having the WRAPAROUND range meaning.
• When checking for containment, intersections or unions — can be handled specially for any axis, in which case the envelope represents an exclusion area instead than an inclusion area.

Since:

0.3

Defined in the sis-referencing module