/*
* OSGeom -- Geometry Collab
*
* (C) 2009, Open Source Geospatial Foundation (OSGeo)
* (C) 2001-2009 Department of Geography, University of Bonn
* (C) 2001-2009 lat/lon GmbH
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
package org.osgeo.geometry.primitive.segments;
import java.util.List;
import org.osgeo.geometry.points.Points;
/**
* {@link CurveSegment} that uses either polynomial or rational interpolation.
* <p>
* Description from the GML 3.1.1 schema:
* <p>
* A B-Spline is a piecewise parametric polynomial or rational curve described in terms of control points and basis
* functions. Knots are breakpoints on the curve that connect its pieces. They are given as a non-decreasing sequence of
* real numbers. If the weights in the knots are equal then it is a polynomial spline. The degree is the algebraic
* degree of the basis functions.
* </p>
*
* @author <a href="mailto:schneider@lat-lon.de">Markus Schneider </a>
* @author last edited by: $Author$
*
* @version $Revision$, $Date$
*/
public interface BSpline extends CurveSegment {
/**
* Returns the control points of the segment.
*
* @return the control points of the segment
*/
public Points getControlPoints();
/**
* Returns the degree of the polynomial used for interpolation in this spline.
*
* @return the degree of the polynomial
*/
public int getPolynomialDegree();
/**
* Returns whether the interpolation is polynomial or rational.
*
* @return true, if the interpolation is polynomial, false if it's rational
*/
public boolean isPolynomial();
/**
* Returns the knots that define the spline basis functions.
*
* @return list of distinctive knots
*/
public List<Knot> getKnots();
}