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/*

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package org.apache.batik.ext.awt.geom;

import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import java.awt.geom.PathIterator;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

/**
 * This class has the same behavior than {@link Polygon2D}, except that
 * the figure is not closed.
 *
 * @version $Id: Polyline2D.java 1808001 2017-09-11 09:51:29Z ssteiner $
 */
public class Polyline2D implements Shape, Cloneable, Serializable {

    private static final float ASSUME_ZERO = 0.001f;

    /**
     * The total number of points.  The value of npoints
     * represents the number of points in this Polyline2D.
     *
     */
    public int npoints;

    /**
     * The array of x coordinates. The value of {@link #npoints npoints} is equal to the
     * number of points in this Polyline2D.
     *
     */
    public float[] xpoints;

    /**
     * The array of x coordinates. The value of {@link #npoints npoints} is equal to the
     * number of points in this Polyline2D.
     *
     */
    public float[] ypoints;

    /**
     * Bounds of the Polyline2D.
     * @see #getBounds()
     */
    protected Rectangle2D bounds;

    private GeneralPath path;
    private GeneralPath closedPath;

    /**
     * Creates an empty Polyline2D.
     */
    public Polyline2D() {
        xpoints = new float[4];
        ypoints = new float[4];
    }

    /**
     * Constructs and initializes a Polyline2D from the specified
     * parameters.
     * @param xpoints an array of x coordinates
     * @param ypoints an array of y coordinates
     * @param npoints the total number of points in the
     *                                Polyline2D
     * @exception  NegativeArraySizeException if the value of
     *                       npoints is negative.
     * @exception  IndexOutOfBoundsException if npoints is
     *             greater than the length of xpoints
     *             or the length of ypoints.
     * @exception  NullPointerException if xpoints or
     *             ypoints is null.
     */
    public Polyline2D(float[] xpoints, float[] ypoints, int npoints) {
        if (npoints > xpoints.length || npoints > ypoints.length) {
            throw new IndexOutOfBoundsException("npoints > xpoints.length || npoints > ypoints.length");
        }
        this.npoints = npoints;
        this.xpoints = new float[npoints+1];   // make space for one more to close the polyline
        this.ypoints = new float[npoints+1];   // make space for one more to close the polyline
        System.arraycopy(xpoints, 0, this.xpoints, 0, npoints);
        System.arraycopy(ypoints, 0, this.ypoints, 0, npoints);
        calculatePath();
    }

    /**
     * Constructs and initializes a Polyline2D from the specified
     * parameters.
     * @param xpoints an array of x coordinates
     * @param ypoints an array of y coordinates
     * @param npoints the total number of points in the Polyline2D
     * @exception  NegativeArraySizeException if the value of
     *                       npoints is negative.
     * @exception  IndexOutOfBoundsException if npoints is
     *             greater than the length of xpoints
     *             or the length of ypoints.
     * @exception  NullPointerException if xpoints or
     *             ypoints is null.
     */
    public Polyline2D(int[] xpoints, int[] ypoints, int npoints) {
        if (npoints > xpoints.length || npoints > ypoints.length) {
            throw new IndexOutOfBoundsException("npoints > xpoints.length || npoints > ypoints.length");
        }
        this.npoints = npoints;
        this.xpoints = new float[npoints];
        this.ypoints = new float[npoints];
        for (int i = 0; i < npoints; i++) {
            this.xpoints[i] = xpoints[i];
            this.ypoints[i] = ypoints[i];
        }
        calculatePath();
    }

    public Polyline2D(Line2D line) {
        npoints = 2;
        xpoints = new float[2];
        ypoints = new float[2];
        xpoints[0] = (float)line.getX1();
        xpoints[1] = (float)line.getX2();
        ypoints[0] = (float)line.getY1();
        ypoints[1] = (float)line.getY2();
        calculatePath();
    }

    /**
     * Resets this Polyline2D object to an empty polygon.
     * The coordinate arrays and the data in them are left untouched
     * but the number of points is reset to zero to mark the old
     * vertex data as invalid and to start accumulating new vertex
     * data at the beginning.
     * All internally-cached data relating to the old vertices
     * are discarded.
     * Note that since the coordinate arrays from before the reset
     * are reused, creating a new empty Polyline2D might
     * be more memory efficient than resetting the current one if
     * the number of vertices in the new polyline data is significantly
     * smaller than the number of vertices in the data from before the
     * reset.
     */
    public void reset() {
        npoints = 0;
        bounds = null;
        path = new GeneralPath();
        closedPath = null;
    }

    public Object clone() {
        Polyline2D pol = new Polyline2D();
        for (int i = 0; i < npoints; i++) {
            pol.addPoint(xpoints[i], ypoints[i]);
        }
        return pol;
    }

    private void calculatePath() {
        path = new GeneralPath();
        path.moveTo(xpoints[0], ypoints[0]);
        for (int i = 1; i < npoints; i++) {
            path.lineTo(xpoints[i], ypoints[i]);
        }
        bounds = path.getBounds2D();
        closedPath = null;
    }

    private void updatePath(float x, float y) {
        closedPath = null;
        if (path == null) {
            path = new GeneralPath(GeneralPath.WIND_EVEN_ODD);
            path.moveTo(x, y);
            bounds = new Rectangle2D.Float(x, y, 0, 0);
        } else {
            path.lineTo(x, y);
            float _xmax = (float)bounds.getMaxX();
            float _ymax = (float)bounds.getMaxY();
            float _xmin = (float)bounds.getMinX();
            float _ymin = (float)bounds.getMinY();
            if (x < _xmin) _xmin = x;
            else if (x > _xmax) _xmax = x;
            if (y < _ymin) _ymin = y;
            else if (y > _ymax) _ymax = y;
            bounds = new Rectangle2D.Float(_xmin, _ymin, _xmax - _xmin, _ymax - _ymin);
        }
    }

    public void addPoint(Point2D p) {
        addPoint((float)p.getX(), (float)p.getY());
    }

    /**
     * Appends the specified coordinates to this Polyline2D.
     * 

* If an operation that calculates the bounding box of this * Polyline2D has already been performed, such as * getBounds or contains, then this * method updates the bounding box. * @param x the specified x coordinate * @param y the specified y coordinate * @see java.awt.Polygon#getBounds * @see java.awt.Polygon#contains(double,double) */ public void addPoint(float x, float y) { if (npoints == xpoints.length) { float[] tmp; tmp = new float[npoints * 2]; System.arraycopy(xpoints, 0, tmp, 0, npoints); xpoints = tmp; tmp = new float[npoints * 2]; System.arraycopy(ypoints, 0, tmp, 0, npoints); ypoints = tmp; } xpoints[npoints] = x; ypoints[npoints] = y; npoints++; updatePath(x, y); } /** * Gets the bounding box of this Polyline2D. * The bounding box is the smallest {@link Rectangle} whose * sides are parallel to the x and y axes of the * coordinate space, and can completely contain the Polyline2D. * @return a Rectangle that defines the bounds of this * Polyline2D. */ public Rectangle getBounds() { if (bounds == null) return null; else return bounds.getBounds(); } private void updateComputingPath() { if (npoints >= 1) { if (closedPath == null) { closedPath = (GeneralPath)path.clone(); closedPath.closePath(); } } } /** * Determines whether the specified {@link Point} is inside this * Polyline2D. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(Point p) { return false; } /** * Determines if the specified coordinates are inside this * Polyline2D. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(double x, double y) { return false; } /** * Determines whether the specified coordinates are inside this * Polyline2D. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(int x, int y) { return false; } /** * Returns the high precision bounding box of the {@link Shape}. * @return a {@link Rectangle2D} that precisely * bounds the Shape. */ public Rectangle2D getBounds2D() { return bounds; } /** * Tests if a specified {@link Point2D} is inside the boundary of this * Polyline2D. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(Point2D p) { return false; } /** * Tests if the interior of this Polygon intersects the * interior of a specified set of rectangular coordinates. * @param x the x coordinate of the specified rectangular * shape's top-left corner * @param y the y coordinate of the specified rectangular * shape's top-left corner * @param w the width of the specified rectangular shape * @param h the height of the specified rectangular shape * @return true if the interior of this * Polygon and the interior of the * specified set of rectangular * coordinates intersect each other; * false otherwise. */ public boolean intersects(double x, double y, double w, double h) { if (npoints <= 0 || !bounds.intersects(x, y, w, h)) { return false; } updateComputingPath(); return closedPath.intersects(x, y, w, h); } /** * Tests if the interior of this Polygon intersects the * interior of a specified Rectangle2D. * @param r a specified Rectangle2D * @return true if this Polygon and the * interior of the specified Rectangle2D * intersect each other; false * otherwise. */ public boolean intersects(Rectangle2D r) { return intersects(r.getX(), r.getY(), r.getWidth(), r.getHeight()); } /** * Tests if the interior of this Polyline2D entirely * contains the specified set of rectangular coordinates. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(double x, double y, double w, double h) { return false; } /** * Tests if the interior of this Polyline2D entirely * contains the specified Rectangle2D. * This method is required to implement the Shape interface, * but in the case of Line2D objects it always returns false since a line contains no area. */ public boolean contains(Rectangle2D r) { return false; } /** * Returns an iterator object that iterates along the boundary of this * Polygon and provides access to the geometry * of the outline of this Polygon. An optional * {@link AffineTransform} can be specified so that the coordinates * returned in the iteration are transformed accordingly. * @param at an optional AffineTransform to be applied to the * coordinates as they are returned in the iteration, or * null if untransformed coordinates are desired * @return a {@link PathIterator} object that provides access to the * geometry of this Polygon. */ public PathIterator getPathIterator(AffineTransform at) { if (path == null) return null; else return path.getPathIterator(at); } /* get the associated {@link Polygon2D}. * This method take care that may be the last point can * be equal to the first. In that case it must not be included in the Polygon, * as polygons declare their first point only once. */ public Polygon2D getPolygon2D() { Polygon2D pol = new Polygon2D(); for (int i = 0; i < npoints - 1; i++) { pol.addPoint(xpoints[i], ypoints[i]); } Point2D.Double p0 = new Point2D.Double(xpoints[0], ypoints[0]); Point2D.Double p1 = new Point2D.Double(xpoints[npoints-1], ypoints[npoints-1]); if (p0.distance(p1) > ASSUME_ZERO) pol.addPoint(xpoints[npoints-1], ypoints[npoints-1]); return pol; } /** * Returns an iterator object that iterates along the boundary of * the Shape and provides access to the geometry of the * outline of the Shape. Only SEG_MOVETO and SEG_LINETO, point types * are returned by the iterator. * Since polylines are already flat, the flatness parameter * is ignored. * @param at an optional AffineTransform to be applied to the * coordinates as they are returned in the iteration, or * null if untransformed coordinates are desired * @param flatness the maximum amount that the control points * for a given curve can vary from colinear before a subdivided * curve is replaced by a straight line connecting the * endpoints. Since polygons are already flat the * flatness parameter is ignored. * @return a PathIterator object that provides access to the * Shape object's geometry. */ public PathIterator getPathIterator(AffineTransform at, double flatness) { return path.getPathIterator(at); } }





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