org.opengis.geometry.coordinate.GenericSurface Maven / Gradle / Ivy
/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2011, Open Source Geospatial Foundation (OSGeo)
* (C) 2003-2005, Open Geospatial Consortium Inc.
*
* All Rights Reserved. http://www.opengis.org/legal/
*/
package org.opengis.geometry.coordinate;
import static org.opengis.annotation.Obligation.*;
import static org.opengis.annotation.Specification.*;
import org.opengis.annotation.UML;
import org.opengis.geometry.DirectPosition;
/**
* Common interface for {@linkplain org.opengis.geometry.primitive.Surface surface} and {@linkplain
* org.opengis.geometry.primitive.SurfacePatch surface patch}. {@code Surface} and {@code
* SurfacePatch} represent sections of surface geometry, and therefore share a number of operation
* signatures.
*
* @version ISO 19107
* @author Martin Desruisseaux (IRD)
* @since GeoAPI 1.0
* @todo Investigate why this interface doesn't extends {@link Geometry}, since it is a cause of
* difficulty with {@link org.opengis.coverage.Coverage}.
*/
@UML(identifier = "GM_GenericSurface", specification = ISO_19107)
public interface GenericSurface {
/**
* Returns a vector perpendicular to the {@code GenericSurface} at the {@linkplain
* DirectPosition direct position} passed, which must be on this {@code GenericSurface}. The
* upward normal always points upward in a manner consistent with the boundary. This means that
* the exterior boundary of the surface is counterclockwise when viewed from the side of the
* surface indicated by the {@code upNormal}. Interior boundaries are clockwise. The side of the
* surface indicated by the {@code upNormal} is referred to as the "top." The function
* "upNormal" shall be continuous and the length of the normal shall always be equal to 1.0.
*
*
*
* NOTE: The upNormal along a boundary of a solid always points
* away from the solid. This is a slight semantics problem in dealing with voids within solids,
* where the upNormal (for sake of mathematical consistency) points into the center of the
* voided region, which linguistically can be considered the interior of the void. What the
* confusion is here is that the basic linguistic metaphors used in most languages for "interior
* of solid" and for "interior of container" use "inward" in inconsistent manners from a
* topological point of view. The void "in" rock is not inside the rock in the same manner as
* the solid material that makes up the substance of the rock. Nor is the coffee "in" the cup
* the same "in" as the ceramic glass "in" the cup. The use of these culturally derived
* metaphors may not be consistent across all languages, some of which may use different
* prepositions for these two different concepts. This specification uses the linguistically
* neutral concept of "interior" derived from mathematics (topology).
*
*
*
* @param point The point on this {@code GenericSurface} where to compute the upNormal.
* @return The upNormal unit vector.
*/
@UML(identifier = "upNormal", obligation = MANDATORY, specification = ISO_19107)
double[] getUpNormal(DirectPosition point);
/**
* Returns the sum of the lengths of all the boundary components of this {@code GenericSurface}.
* Since perimeter, like length, is an accumulation (integral) of distance, its return value
* shall be in a reference system appropriate for measuring distances.
*
*
*
* NOTE: The perimeter is defined as the sum of the lengths of
* all boundary components. The length of a curve or of a collection of curves is always
* positive and non-zero (unless the curve is pathological). This means that holes in surfaces
* will contribute positively to the total perimeter.
*
*
*
* @return The perimeter.
* @unitof Length
*/
@UML(identifier = "perimeter", obligation = MANDATORY, specification = ISO_19107)
double getPerimeter();
/**
* Returns the area of this {@code GenericSurface}. The area of a 2-dimensional geometric object
* shall be a numeric measure of its surface area (in a square unit of distance). Since area is
* an accumulation (integral) of the product of two distances, its return value shall be in a
* unit of measure appropriate for measuring distances squared, such as meters squared
* (m2).
*
*
*
* NOTE: Consistent with the definition of surface as a set of
* {@linkplain DirectPosition direct positions}, holes in the surfaces will not contribute to
* the total area. If the usual Green's Theorem (or more general Stokes' Theorem) integral is
* used, the integral around the holes in the surface are subtracted from the integral about the
* exterior of the surface patch.
*
*
*
* @return The area.
* @unitof Area
*/
@UML(identifier = "area", obligation = MANDATORY, specification = ISO_19107)
double getArea();
}