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	/*
	* Copyright (c) 1997, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.awt.geom;

	import java.util.*;

	/**
	* A utility class to iterate over the path segments of an rounded rectangle
	* through the PathIterator interface.
	*
	* @author Jim Graham
	*/
	class RoundRectIterator implements PathIterator {
	double x, y, w, h, aw, ah;
	AffineTransform affine;
	int index;

	RoundRectIterator(RoundRectangle2D rr, AffineTransform at) {
	this.x = rr.getX();
	this.y = rr.getY();
	this.w = rr.getWidth();
	this.h = rr.getHeight();
	this.aw = Math.min(w, Math.abs(rr.getArcWidth()));
	this.ah = Math.min(h, Math.abs(rr.getArcHeight()));
	this.affine = at;
	if (aw < 0 \|\| ah < 0) {
	// Don't draw anything...
	index = ctrlpts.length;
	}
	}

	/**
	* Return the winding rule for determining the insideness of the
	* path.
	* @see #WIND_EVEN_ODD
	* @see #WIND_NON_ZERO
	*/
	public int getWindingRule() {
	return WIND_NON_ZERO;
	}

	/**
	* Tests if there are more points to read.
	* @return true if there are more points to read
	*/
	public boolean isDone() {
	return index >= ctrlpts.length;
	}

	/**
	* Moves the iterator to the next segment of the path forwards
	* along the primary direction of traversal as long as there are
	* more points in that direction.
	*/
	public void next() {
	index++;
	}

	private static final double angle = Math.PI / 4.0;
	private static final double a = 1.0 - Math.cos(angle);
	private static final double b = Math.tan(angle);
	private static final double c = Math.sqrt(1.0 + b * b) - 1 + a;
	private static final double cv = 4.0 / 3.0 * a * b / c;
	private static final double acv = (1.0 - cv) / 2.0;

	// For each array:
	// 4 values for each point {v0, v1, v2, v3}:
	// point = (x + v0 * w + v1 * arcWidth,
	// y + v2 * h + v3 * arcHeight);
	private static double ctrlpts[][] = {
	{ 0.0, 0.0, 0.0, 0.5 },
	{ 0.0, 0.0, 1.0, -0.5 },
	{ 0.0, 0.0, 1.0, -acv,
	0.0, acv, 1.0, 0.0,
	0.0, 0.5, 1.0, 0.0 },
	{ 1.0, -0.5, 1.0, 0.0 },
	{ 1.0, -acv, 1.0, 0.0,
	1.0, 0.0, 1.0, -acv,
	1.0, 0.0, 1.0, -0.5 },
	{ 1.0, 0.0, 0.0, 0.5 },
	{ 1.0, 0.0, 0.0, acv,
	1.0, -acv, 0.0, 0.0,
	1.0, -0.5, 0.0, 0.0 },
	{ 0.0, 0.5, 0.0, 0.0 },
	{ 0.0, acv, 0.0, 0.0,
	0.0, 0.0, 0.0, acv,
	0.0, 0.0, 0.0, 0.5 },
	{},
	};
	private static int types[] = {
	SEG_MOVETO,
	SEG_LINETO, SEG_CUBICTO,
	SEG_LINETO, SEG_CUBICTO,
	SEG_LINETO, SEG_CUBICTO,
	SEG_LINETO, SEG_CUBICTO,
	SEG_CLOSE,
	};

	/**
	* Returns the coordinates and type of the current path segment in
	* the iteration.
	* The return value is the path segment type:
	* SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
	* A float array of length 6 must be passed in and may be used to
	* store the coordinates of the point(s).
	* Each point is stored as a pair of float x,y coordinates.
	* SEG_MOVETO and SEG_LINETO types will return one point,
	* SEG_QUADTO will return two points,
	* SEG_CUBICTO will return 3 points
	* and SEG_CLOSE will not return any points.
	* @see #SEG_MOVETO
	* @see #SEG_LINETO
	* @see #SEG_QUADTO
	* @see #SEG_CUBICTO
	* @see #SEG_CLOSE
	*/
	public int currentSegment(float[] coords) {
	if (isDone()) {
	throw new NoSuchElementException("roundrect iterator out of bounds");
	}
	double ctrls[] = ctrlpts[index];
	int nc = 0;
	for (int i = 0; i < ctrls.length; i += 4) {
	coords[nc++] = (float) (x + ctrls[i + 0] * w + ctrls[i + 1] * aw);
	coords[nc++] = (float) (y + ctrls[i + 2] * h + ctrls[i + 3] * ah);
	}
	if (affine != null) {
	affine.transform(coords, 0, coords, 0, nc / 2);
	}
	return types[index];
	}

	/**
	* Returns the coordinates and type of the current path segment in
	* the iteration.
	* The return value is the path segment type:
	* SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
	* A double array of length 6 must be passed in and may be used to
	* store the coordinates of the point(s).
	* Each point is stored as a pair of double x,y coordinates.
	* SEG_MOVETO and SEG_LINETO types will return one point,
	* SEG_QUADTO will return two points,
	* SEG_CUBICTO will return 3 points
	* and SEG_CLOSE will not return any points.
	* @see #SEG_MOVETO
	* @see #SEG_LINETO
	* @see #SEG_QUADTO
	* @see #SEG_CUBICTO
	* @see #SEG_CLOSE
	*/
	public int currentSegment(double[] coords) {
	if (isDone()) {
	throw new NoSuchElementException("roundrect iterator out of bounds");
	}
	double ctrls[] = ctrlpts[index];
	int nc = 0;
	for (int i = 0; i < ctrls.length; i += 4) {
	coords[nc++] = (x + ctrls[i + 0] * w + ctrls[i + 1] * aw);
	coords[nc++] = (y + ctrls[i + 2] * h + ctrls[i + 3] * ah);
	}
	if (affine != null) {
	affine.transform(coords, 0, coords, 0, nc / 2);
	}
	return types[index];
	}
	}

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