001 /*
002 * GeoAPI - Java interfaces for OGC/ISO standards
003 * http://www.geoapi.org
004 *
005 * Copyright (C) 2005-2012 Open Geospatial Consortium, Inc.
006 * All Rights Reserved. http://www.opengeospatial.org/ogc/legal
007 *
008 * Permission to use, copy, and modify this software and its documentation, with
009 * or without modification, for any purpose and without fee or royalty is hereby
010 * granted, provided that you include the following on ALL copies of the software
011 * and documentation or portions thereof, including modifications, that you make:
012 *
013 * 1. The full text of this NOTICE in a location viewable to users of the
014 * redistributed or derivative work.
015 * 2. Notice of any changes or modifications to the OGC files, including the
016 * date changes were made.
017 *
018 * THIS SOFTWARE AND DOCUMENTATION IS PROVIDED "AS IS," AND COPYRIGHT HOLDERS MAKE
019 * NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
020 * TO, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT
021 * THE USE OF THE SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY THIRD PARTY
022 * PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS.
023 *
024 * COPYRIGHT HOLDERS WILL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL OR
025 * CONSEQUENTIAL DAMAGES ARISING OUT OF ANY USE OF THE SOFTWARE OR DOCUMENTATION.
026 *
027 * The name and trademarks of copyright holders may NOT be used in advertising or
028 * publicity pertaining to the software without specific, written prior permission.
029 * Title to copyright in this software and any associated documentation will at all
030 * times remain with copyright holders.
031 */
032 package org.opengis.geometry.coordinate;
033
034 import org.opengis.annotation.UML;
035
036 import static org.opengis.annotation.Obligation.*;
037 import static org.opengis.annotation.Specification.*;
038
039
040 /**
041 * A piecewise parametric polynomial or rational curve described
042 * in terms of control points and basis functions. If the weights in the knots are equal
043 * then it is a polynomial spline. If not, then it is a rational function spline. If
044 * the boolean {@link #isPolynomial} is set to {@code true} then the weights shall all be set to 1.
045 * A B-spline curve is a piecewise Bézier curve if it is quasi-uniform except that the
046 * interior knots have multiplicity "degree" rather than having multiplicity one. In
047 * this subtype the knot spacing shall be 1.0, starting at 0.0. A piecewise Bézier curve
048 * that has only two knots, 0.0, and 1.0, each of multiplicity (degree+1), is equivalent
049 * to a simple Bézier curve.
050 *
051 * @version <A HREF="http://www.opengeospatial.org/standards/as">ISO 19107</A>
052 * @author Martin Desruisseaux (IRD)
053 * @since GeoAPI 2.0
054 *
055 * @see GeometryFactory#createBSplineCurve
056 */
057 @UML(identifier="GM_BSplineCurve", specification=ISO_19107)
058 public interface BSplineCurve extends SplineCurve {
059 /**
060 * The algebraic degree of the basis functions.
061 */
062 @UML(identifier="degree", obligation=MANDATORY, specification=ISO_19107)
063 int getDegree();
064
065 /**
066 * Identifies particular types of curve which this spline is being used to
067 * approximate. It is for information only, used to capture the original intention.
068 * If no such approximation is intended, then the value of this attribute is {@code null}.
069 */
070 @UML(identifier="curveForm", obligation=OPTIONAL, specification=ISO_19107)
071 SplineCurveForm getCurveForm();
072
073 /**
074 * Gives the type of knot distribution used in defining this spline.
075 * This is for information only and is set according to the different construction-functions.
076 */
077 @UML(identifier="knotSpec", obligation=OPTIONAL, specification=ISO_19107)
078 KnotType getKnotSpec();
079
080 /**
081 * {@code true} if this is a polynomial spline.
082 */
083 @UML(identifier="isPolynomial", obligation=MANDATORY, specification=ISO_19107)
084 boolean isPolynomial();
085 }