/* |
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* Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.awt.geom; |
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import java.awt.Shape; |
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import java.awt.Rectangle; |
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import java.util.Arrays; |
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import java.io.Serializable; |
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import sun.awt.geom.Curve; |
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import static java.lang.Math.abs; |
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import static java.lang.Math.max; |
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import static java.lang.Math.ulp; |
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/** |
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* The <code>CubicCurve2D</code> class defines a cubic parametric curve |
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* segment in {@code (x,y)} coordinate space. |
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* <p> |
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* This class is only the abstract superclass for all objects which |
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* store a 2D cubic curve segment. |
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* The actual storage representation of the coordinates is left to |
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* the subclass. |
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* |
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* @author Jim Graham |
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* @since 1.2 |
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*/ |
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public abstract class CubicCurve2D implements Shape, Cloneable { |
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/** |
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* A cubic parametric curve segment specified with |
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* {@code float} coordinates. |
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* @since 1.2 |
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*/ |
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public static class Float extends CubicCurve2D implements Serializable { |
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/** |
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* The X coordinate of the start point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float x1; |
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/** |
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* The Y coordinate of the start point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float y1; |
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/** |
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* The X coordinate of the first control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float ctrlx1; |
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/** |
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* The Y coordinate of the first control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float ctrly1; |
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/** |
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* The X coordinate of the second control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float ctrlx2; |
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/** |
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* The Y coordinate of the second control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float ctrly2; |
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/** |
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* The X coordinate of the end point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float x2; |
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/** |
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* The Y coordinate of the end point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public float y2; |
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/** |
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* Constructs and initializes a CubicCurve with coordinates |
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* (0, 0, 0, 0, 0, 0, 0, 0). |
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* @since 1.2 |
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*/ |
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public Float() { |
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} |
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/** |
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* Constructs and initializes a {@code CubicCurve2D} from |
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* the specified {@code float} coordinates. |
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* |
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* @param x1 the X coordinate for the start point |
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* of the resulting {@code CubicCurve2D} |
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* @param y1 the Y coordinate for the start point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrlx1 the X coordinate for the first control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrly1 the Y coordinate for the first control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrlx2 the X coordinate for the second control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrly2 the Y coordinate for the second control point |
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* of the resulting {@code CubicCurve2D} |
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* @param x2 the X coordinate for the end point |
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* of the resulting {@code CubicCurve2D} |
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* @param y2 the Y coordinate for the end point |
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* of the resulting {@code CubicCurve2D} |
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* @since 1.2 |
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*/ |
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public Float(float x1, float y1, |
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float ctrlx1, float ctrly1, |
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float ctrlx2, float ctrly2, |
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float x2, float y2) |
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{ |
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setCurve(x1, y1, ctrlx1, ctrly1, ctrlx2, ctrly2, x2, y2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getX1() { |
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return (double) x1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getY1() { |
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return (double) y1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getP1() { |
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return new Point2D.Float(x1, y1); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlX1() { |
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return (double) ctrlx1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlY1() { |
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return (double) ctrly1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getCtrlP1() { |
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return new Point2D.Float(ctrlx1, ctrly1); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlX2() { |
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return (double) ctrlx2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlY2() { |
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return (double) ctrly2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getCtrlP2() { |
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return new Point2D.Float(ctrlx2, ctrly2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getX2() { |
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return (double) x2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getY2() { |
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return (double) y2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getP2() { |
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return new Point2D.Float(x2, y2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public void setCurve(double x1, double y1, |
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double ctrlx1, double ctrly1, |
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double ctrlx2, double ctrly2, |
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double x2, double y2) |
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{ |
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this.x1 = (float) x1; |
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this.y1 = (float) y1; |
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this.ctrlx1 = (float) ctrlx1; |
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this.ctrly1 = (float) ctrly1; |
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this.ctrlx2 = (float) ctrlx2; |
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this.ctrly2 = (float) ctrly2; |
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this.x2 = (float) x2; |
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this.y2 = (float) y2; |
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} |
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/** |
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* Sets the location of the end points and control points |
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* of this curve to the specified {@code float} coordinates. |
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* |
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* @param x1 the X coordinate used to set the start point |
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* of this {@code CubicCurve2D} |
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* @param y1 the Y coordinate used to set the start point |
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* of this {@code CubicCurve2D} |
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* @param ctrlx1 the X coordinate used to set the first control point |
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* of this {@code CubicCurve2D} |
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* @param ctrly1 the Y coordinate used to set the first control point |
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* of this {@code CubicCurve2D} |
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* @param ctrlx2 the X coordinate used to set the second control point |
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* of this {@code CubicCurve2D} |
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* @param ctrly2 the Y coordinate used to set the second control point |
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* of this {@code CubicCurve2D} |
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* @param x2 the X coordinate used to set the end point |
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* of this {@code CubicCurve2D} |
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* @param y2 the Y coordinate used to set the end point |
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* of this {@code CubicCurve2D} |
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* @since 1.2 |
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*/ |
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public void setCurve(float x1, float y1, |
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float ctrlx1, float ctrly1, |
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float ctrlx2, float ctrly2, |
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float x2, float y2) |
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{ |
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this.x1 = x1; |
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this.y1 = y1; |
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this.ctrlx1 = ctrlx1; |
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this.ctrly1 = ctrly1; |
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this.ctrlx2 = ctrlx2; |
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this.ctrly2 = ctrly2; |
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this.x2 = x2; |
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this.y2 = y2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Rectangle2D getBounds2D() { |
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float left = Math.min(Math.min(x1, x2), |
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Math.min(ctrlx1, ctrlx2)); |
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float top = Math.min(Math.min(y1, y2), |
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Math.min(ctrly1, ctrly2)); |
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float right = Math.max(Math.max(x1, x2), |
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Math.max(ctrlx1, ctrlx2)); |
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float bottom = Math.max(Math.max(y1, y2), |
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Math.max(ctrly1, ctrly2)); |
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return new Rectangle2D.Float(left, top, |
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right - left, bottom - top); |
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} |
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/* |
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* JDK 1.6 serialVersionUID |
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*/ |
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private static final long serialVersionUID = -1272015596714244385L; |
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} |
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/** |
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* A cubic parametric curve segment specified with |
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* {@code double} coordinates. |
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* @since 1.2 |
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*/ |
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public static class Double extends CubicCurve2D implements Serializable { |
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/** |
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* The X coordinate of the start point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double x1; |
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/** |
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* The Y coordinate of the start point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double y1; |
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/** |
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* The X coordinate of the first control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double ctrlx1; |
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/** |
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* The Y coordinate of the first control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double ctrly1; |
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/** |
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* The X coordinate of the second control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double ctrlx2; |
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/** |
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* The Y coordinate of the second control point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double ctrly2; |
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/** |
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* The X coordinate of the end point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double x2; |
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/** |
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* The Y coordinate of the end point |
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* of the cubic curve segment. |
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* @since 1.2 |
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* @serial |
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*/ |
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public double y2; |
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/** |
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* Constructs and initializes a CubicCurve with coordinates |
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* (0, 0, 0, 0, 0, 0, 0, 0). |
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* @since 1.2 |
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*/ |
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public Double() { |
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} |
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/** |
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* Constructs and initializes a {@code CubicCurve2D} from |
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* the specified {@code double} coordinates. |
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* |
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* @param x1 the X coordinate for the start point |
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* of the resulting {@code CubicCurve2D} |
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* @param y1 the Y coordinate for the start point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrlx1 the X coordinate for the first control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrly1 the Y coordinate for the first control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrlx2 the X coordinate for the second control point |
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* of the resulting {@code CubicCurve2D} |
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* @param ctrly2 the Y coordinate for the second control point |
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* of the resulting {@code CubicCurve2D} |
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* @param x2 the X coordinate for the end point |
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* of the resulting {@code CubicCurve2D} |
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* @param y2 the Y coordinate for the end point |
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* of the resulting {@code CubicCurve2D} |
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* @since 1.2 |
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*/ |
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public Double(double x1, double y1, |
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double ctrlx1, double ctrly1, |
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double ctrlx2, double ctrly2, |
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double x2, double y2) |
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{ |
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setCurve(x1, y1, ctrlx1, ctrly1, ctrlx2, ctrly2, x2, y2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getX1() { |
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return x1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getY1() { |
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return y1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getP1() { |
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return new Point2D.Double(x1, y1); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlX1() { |
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return ctrlx1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlY1() { |
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return ctrly1; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getCtrlP1() { |
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return new Point2D.Double(ctrlx1, ctrly1); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlX2() { |
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return ctrlx2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getCtrlY2() { |
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return ctrly2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getCtrlP2() { |
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return new Point2D.Double(ctrlx2, ctrly2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getX2() { |
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return x2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public double getY2() { |
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return y2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Point2D getP2() { |
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return new Point2D.Double(x2, y2); |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public void setCurve(double x1, double y1, |
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double ctrlx1, double ctrly1, |
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double ctrlx2, double ctrly2, |
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double x2, double y2) |
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{ |
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this.x1 = x1; |
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this.y1 = y1; |
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this.ctrlx1 = ctrlx1; |
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this.ctrly1 = ctrly1; |
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this.ctrlx2 = ctrlx2; |
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this.ctrly2 = ctrly2; |
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this.x2 = x2; |
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this.y2 = y2; |
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} |
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/** |
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* {@inheritDoc} |
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* @since 1.2 |
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*/ |
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public Rectangle2D getBounds2D() { |
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double left = Math.min(Math.min(x1, x2), |
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Math.min(ctrlx1, ctrlx2)); |
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double top = Math.min(Math.min(y1, y2), |
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Math.min(ctrly1, ctrly2)); |
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double right = Math.max(Math.max(x1, x2), |
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Math.max(ctrlx1, ctrlx2)); |
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double bottom = Math.max(Math.max(y1, y2), |
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Math.max(ctrly1, ctrly2)); |
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return new Rectangle2D.Double(left, top, |
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right - left, bottom - top); |
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} |
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/* |
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* JDK 1.6 serialVersionUID |
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*/ |
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private static final long serialVersionUID = -4202960122839707295L; |
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} |
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/** |
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* This is an abstract class that cannot be instantiated directly. |
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* Type-specific implementation subclasses are available for |
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* instantiation and provide a number of formats for storing |
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* the information necessary to satisfy the various accessor |
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* methods below. |
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* |
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* @see java.awt.geom.CubicCurve2D.Float |
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* @see java.awt.geom.CubicCurve2D.Double |
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* @since 1.2 |
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*/ |
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protected CubicCurve2D() { |
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} |
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/** |
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* Returns the X coordinate of the start point in double precision. |
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* @return the X coordinate of the start point of the |
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* {@code CubicCurve2D}. |
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* @since 1.2 |
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*/ |
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public abstract double getX1(); |
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/** |
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* Returns the Y coordinate of the start point in double precision. |
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* @return the Y coordinate of the start point of the |
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* {@code CubicCurve2D}. |
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* @since 1.2 |
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*/ |
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public abstract double getY1(); |
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/** |
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* Returns the start point. |
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* @return a {@code Point2D} that is the start point of |
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* the {@code CubicCurve2D}. |
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* @since 1.2 |
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*/ |
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public abstract Point2D getP1(); |
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/** |
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* Returns the X coordinate of the first control point in double precision. |
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* @return the X coordinate of the first control point of the |
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* {@code CubicCurve2D}. |
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* @since 1.2 |
|
*/ |
|
public abstract double getCtrlX1(); |
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/** |
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* Returns the Y coordinate of the first control point in double precision. |
|
* @return the Y coordinate of the first control point of the |
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* {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract double getCtrlY1(); |
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/** |
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* Returns the first control point. |
|
* @return a {@code Point2D} that is the first control point of |
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* the {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract Point2D getCtrlP1(); |
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/** |
|
* Returns the X coordinate of the second control point |
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* in double precision. |
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* @return the X coordinate of the second control point of the |
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* {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract double getCtrlX2(); |
|
/** |
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* Returns the Y coordinate of the second control point |
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* in double precision. |
|
* @return the Y coordinate of the second control point of the |
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* {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract double getCtrlY2(); |
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/** |
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* Returns the second control point. |
|
* @return a {@code Point2D} that is the second control point of |
|
* the {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract Point2D getCtrlP2(); |
|
/** |
|
* Returns the X coordinate of the end point in double precision. |
|
* @return the X coordinate of the end point of the |
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* {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract double getX2(); |
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/** |
|
* Returns the Y coordinate of the end point in double precision. |
|
* @return the Y coordinate of the end point of the |
|
* {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract double getY2(); |
|
/** |
|
* Returns the end point. |
|
* @return a {@code Point2D} that is the end point of |
|
* the {@code CubicCurve2D}. |
|
* @since 1.2 |
|
*/ |
|
public abstract Point2D getP2(); |
|
/** |
|
* Sets the location of the end points and control points of this curve |
|
* to the specified double coordinates. |
|
* |
|
* @param x1 the X coordinate used to set the start point |
|
* of this {@code CubicCurve2D} |
|
* @param y1 the Y coordinate used to set the start point |
|
* of this {@code CubicCurve2D} |
|
* @param ctrlx1 the X coordinate used to set the first control point |
|
* of this {@code CubicCurve2D} |
|
* @param ctrly1 the Y coordinate used to set the first control point |
|
* of this {@code CubicCurve2D} |
|
* @param ctrlx2 the X coordinate used to set the second control point |
|
* of this {@code CubicCurve2D} |
|
* @param ctrly2 the Y coordinate used to set the second control point |
|
* of this {@code CubicCurve2D} |
|
* @param x2 the X coordinate used to set the end point |
|
* of this {@code CubicCurve2D} |
|
* @param y2 the Y coordinate used to set the end point |
|
* of this {@code CubicCurve2D} |
|
* @since 1.2 |
|
*/ |
|
public abstract void setCurve(double x1, double y1, |
|
double ctrlx1, double ctrly1, |
|
double ctrlx2, double ctrly2, |
|
double x2, double y2); |
|
/** |
|
* Sets the location of the end points and control points of this curve |
|
* to the double coordinates at the specified offset in the specified |
|
* array. |
|
* @param coords a double array containing coordinates |
|
* @param offset the index of <code>coords</code> from which to begin |
|
* setting the end points and control points of this curve |
|
* to the coordinates contained in <code>coords</code> |
|
* @since 1.2 |
|
*/ |
|
public void setCurve(double[] coords, int offset) { |
|
setCurve(coords[offset + 0], coords[offset + 1], |
|
coords[offset + 2], coords[offset + 3], |
|
coords[offset + 4], coords[offset + 5], |
|
coords[offset + 6], coords[offset + 7]); |
|
} |
|
/** |
|
* Sets the location of the end points and control points of this curve |
|
* to the specified <code>Point2D</code> coordinates. |
|
* @param p1 the first specified <code>Point2D</code> used to set the |
|
* start point of this curve |
|
* @param cp1 the second specified <code>Point2D</code> used to set the |
|
* first control point of this curve |
|
* @param cp2 the third specified <code>Point2D</code> used to set the |
|
* second control point of this curve |
|
* @param p2 the fourth specified <code>Point2D</code> used to set the |
|
* end point of this curve |
|
* @since 1.2 |
|
*/ |
|
public void setCurve(Point2D p1, Point2D cp1, Point2D cp2, Point2D p2) { |
|
setCurve(p1.getX(), p1.getY(), cp1.getX(), cp1.getY(), |
|
cp2.getX(), cp2.getY(), p2.getX(), p2.getY()); |
|
} |
|
/** |
|
* Sets the location of the end points and control points of this curve |
|
* to the coordinates of the <code>Point2D</code> objects at the specified |
|
* offset in the specified array. |
|
* @param pts an array of <code>Point2D</code> objects |
|
* @param offset the index of <code>pts</code> from which to begin setting |
|
* the end points and control points of this curve to the |
|
* points contained in <code>pts</code> |
|
* @since 1.2 |
|
*/ |
|
public void setCurve(Point2D[] pts, int offset) { |
|
setCurve(pts[offset + 0].getX(), pts[offset + 0].getY(), |
|
pts[offset + 1].getX(), pts[offset + 1].getY(), |
|
pts[offset + 2].getX(), pts[offset + 2].getY(), |
|
pts[offset + 3].getX(), pts[offset + 3].getY()); |
|
} |
|
/** |
|
* Sets the location of the end points and control points of this curve |
|
* to the same as those in the specified <code>CubicCurve2D</code>. |
|
* @param c the specified <code>CubicCurve2D</code> |
|
* @since 1.2 |
|
*/ |
|
public void setCurve(CubicCurve2D c) { |
|
setCurve(c.getX1(), c.getY1(), c.getCtrlX1(), c.getCtrlY1(), |
|
c.getCtrlX2(), c.getCtrlY2(), c.getX2(), c.getY2()); |
|
} |
|
/** |
|
* Returns the square of the flatness of the cubic curve specified |
|
* by the indicated control points. The flatness is the maximum distance |
|
* of a control point from the line connecting the end points. |
|
* |
|
* @param x1 the X coordinate that specifies the start point |
|
* of a {@code CubicCurve2D} |
|
* @param y1 the Y coordinate that specifies the start point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrlx1 the X coordinate that specifies the first control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrly1 the Y coordinate that specifies the first control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrlx2 the X coordinate that specifies the second control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrly2 the Y coordinate that specifies the second control point |
|
* of a {@code CubicCurve2D} |
|
* @param x2 the X coordinate that specifies the end point |
|
* of a {@code CubicCurve2D} |
|
* @param y2 the Y coordinate that specifies the end point |
|
* of a {@code CubicCurve2D} |
|
* @return the square of the flatness of the {@code CubicCurve2D} |
|
* represented by the specified coordinates. |
|
* @since 1.2 |
|
*/ |
|
public static double getFlatnessSq(double x1, double y1, |
|
double ctrlx1, double ctrly1, |
|
double ctrlx2, double ctrly2, |
|
double x2, double y2) { |
|
return Math.max(Line2D.ptSegDistSq(x1, y1, x2, y2, ctrlx1, ctrly1), |
|
Line2D.ptSegDistSq(x1, y1, x2, y2, ctrlx2, ctrly2)); |
|
} |
|
/** |
|
* Returns the flatness of the cubic curve specified |
|
* by the indicated control points. The flatness is the maximum distance |
|
* of a control point from the line connecting the end points. |
|
* |
|
* @param x1 the X coordinate that specifies the start point |
|
* of a {@code CubicCurve2D} |
|
* @param y1 the Y coordinate that specifies the start point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrlx1 the X coordinate that specifies the first control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrly1 the Y coordinate that specifies the first control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrlx2 the X coordinate that specifies the second control point |
|
* of a {@code CubicCurve2D} |
|
* @param ctrly2 the Y coordinate that specifies the second control point |
|
* of a {@code CubicCurve2D} |
|
* @param x2 the X coordinate that specifies the end point |
|
* of a {@code CubicCurve2D} |
|
* @param y2 the Y coordinate that specifies the end point |
|
* of a {@code CubicCurve2D} |
|
* @return the flatness of the {@code CubicCurve2D} |
|
* represented by the specified coordinates. |
|
* @since 1.2 |
|
*/ |
|
public static double getFlatness(double x1, double y1, |
|
double ctrlx1, double ctrly1, |
|
double ctrlx2, double ctrly2, |
|
double x2, double y2) { |
|
return Math.sqrt(getFlatnessSq(x1, y1, ctrlx1, ctrly1, |
|
ctrlx2, ctrly2, x2, y2)); |
|
} |
|
/** |
|
* Returns the square of the flatness of the cubic curve specified |
|
* by the control points stored in the indicated array at the |
|
* indicated index. The flatness is the maximum distance |
|
* of a control point from the line connecting the end points. |
|
* @param coords an array containing coordinates |
|
* @param offset the index of <code>coords</code> from which to begin |
|
* getting the end points and control points of the curve |
|
* @return the square of the flatness of the <code>CubicCurve2D</code> |
|
* specified by the coordinates in <code>coords</code> at |
|
* the specified offset. |
|
* @since 1.2 |
|
*/ |
|
public static double getFlatnessSq(double coords[], int offset) { |
|
return getFlatnessSq(coords[offset + 0], coords[offset + 1], |
|
coords[offset + 2], coords[offset + 3], |
|
coords[offset + 4], coords[offset + 5], |
|
coords[offset + 6], coords[offset + 7]); |
|
} |
|
/** |
|
* Returns the flatness of the cubic curve specified |
|
* by the control points stored in the indicated array at the |
|
* indicated index. The flatness is the maximum distance |
|
* of a control point from the line connecting the end points. |
|
* @param coords an array containing coordinates |
|
* @param offset the index of <code>coords</code> from which to begin |
|
* getting the end points and control points of the curve |
|
* @return the flatness of the <code>CubicCurve2D</code> |
|
* specified by the coordinates in <code>coords</code> at |
|
* the specified offset. |
|
* @since 1.2 |
|
*/ |
|
public static double getFlatness(double coords[], int offset) { |
|
return getFlatness(coords[offset + 0], coords[offset + 1], |
|
coords[offset + 2], coords[offset + 3], |
|
coords[offset + 4], coords[offset + 5], |
|
coords[offset + 6], coords[offset + 7]); |
|
} |
|
/** |
|
* Returns the square of the flatness of this curve. The flatness is the |
|
* maximum distance of a control point from the line connecting the |
|
* end points. |
|
* @return the square of the flatness of this curve. |
|
* @since 1.2 |
|
*/ |
|
public double getFlatnessSq() { |
|
return getFlatnessSq(getX1(), getY1(), getCtrlX1(), getCtrlY1(), |
|
getCtrlX2(), getCtrlY2(), getX2(), getY2()); |
|
} |
|
/** |
|
* Returns the flatness of this curve. The flatness is the |
|
* maximum distance of a control point from the line connecting the |
|
* end points. |
|
* @return the flatness of this curve. |
|
* @since 1.2 |
|
*/ |
|
public double getFlatness() { |
|
return getFlatness(getX1(), getY1(), getCtrlX1(), getCtrlY1(), |
|
getCtrlX2(), getCtrlY2(), getX2(), getY2()); |
|
} |
|
/** |
|
* Subdivides this cubic curve and stores the resulting two |
|
* subdivided curves into the left and right curve parameters. |
|
* Either or both of the left and right objects may be the same |
|
* as this object or null. |
|
* @param left the cubic curve object for storing for the left or |
|
* first half of the subdivided curve |
|
* @param right the cubic curve object for storing for the right or |
|
* second half of the subdivided curve |
|
* @since 1.2 |
|
*/ |
|
public void subdivide(CubicCurve2D left, CubicCurve2D right) { |
|
subdivide(this, left, right); |
|
} |
|
/** |
|
* Subdivides the cubic curve specified by the <code>src</code> parameter |
|
* and stores the resulting two subdivided curves into the |
|
* <code>left</code> and <code>right</code> curve parameters. |
|
* Either or both of the <code>left</code> and <code>right</code> objects |
|
* may be the same as the <code>src</code> object or <code>null</code>. |
|
* @param src the cubic curve to be subdivided |
|
* @param left the cubic curve object for storing the left or |
|
* first half of the subdivided curve |
|
* @param right the cubic curve object for storing the right or |
|
* second half of the subdivided curve |
|
* @since 1.2 |
|
*/ |
|
public static void subdivide(CubicCurve2D src, |
|
CubicCurve2D left, |
|
CubicCurve2D right) { |
|
double x1 = src.getX1(); |
|
double y1 = src.getY1(); |
|
double ctrlx1 = src.getCtrlX1(); |
|
double ctrly1 = src.getCtrlY1(); |
|
double ctrlx2 = src.getCtrlX2(); |
|
double ctrly2 = src.getCtrlY2(); |
|
double x2 = src.getX2(); |
|
double y2 = src.getY2(); |
|
double centerx = (ctrlx1 + ctrlx2) / 2.0; |
|
double centery = (ctrly1 + ctrly2) / 2.0; |
|
ctrlx1 = (x1 + ctrlx1) / 2.0; |
|
ctrly1 = (y1 + ctrly1) / 2.0; |
|
ctrlx2 = (x2 + ctrlx2) / 2.0; |
|
ctrly2 = (y2 + ctrly2) / 2.0; |
|
double ctrlx12 = (ctrlx1 + centerx) / 2.0; |
|
double ctrly12 = (ctrly1 + centery) / 2.0; |
|
double ctrlx21 = (ctrlx2 + centerx) / 2.0; |
|
double ctrly21 = (ctrly2 + centery) / 2.0; |
|
centerx = (ctrlx12 + ctrlx21) / 2.0; |
|
centery = (ctrly12 + ctrly21) / 2.0; |
|
if (left != null) { |
|
left.setCurve(x1, y1, ctrlx1, ctrly1, |
|
ctrlx12, ctrly12, centerx, centery); |
|
} |
|
if (right != null) { |
|
right.setCurve(centerx, centery, ctrlx21, ctrly21, |
|
ctrlx2, ctrly2, x2, y2); |
|
} |
|
} |
|
/** |
|
* Subdivides the cubic curve specified by the coordinates |
|
* stored in the <code>src</code> array at indices <code>srcoff</code> |
|
* through (<code>srcoff</code> + 7) and stores the |
|
* resulting two subdivided curves into the two result arrays at the |
|
* corresponding indices. |
|
* Either or both of the <code>left</code> and <code>right</code> |
|
* arrays may be <code>null</code> or a reference to the same array |
|
* as the <code>src</code> array. |
|
* Note that the last point in the first subdivided curve is the |
|
* same as the first point in the second subdivided curve. Thus, |
|
* it is possible to pass the same array for <code>left</code> |
|
* and <code>right</code> and to use offsets, such as <code>rightoff</code> |
|
* equals (<code>leftoff</code> + 6), in order |
|
* to avoid allocating extra storage for this common point. |
|
* @param src the array holding the coordinates for the source curve |
|
* @param srcoff the offset into the array of the beginning of the |
|
* the 6 source coordinates |
|
* @param left the array for storing the coordinates for the first |
|
* half of the subdivided curve |
|
* @param leftoff the offset into the array of the beginning of the |
|
* the 6 left coordinates |
|
* @param right the array for storing the coordinates for the second |
|
* half of the subdivided curve |
|
* @param rightoff the offset into the array of the beginning of the |
|
* the 6 right coordinates |
|
* @since 1.2 |
|
*/ |
|
public static void subdivide(double src[], int srcoff, |
|
double left[], int leftoff, |
|
double right[], int rightoff) { |
|
double x1 = src[srcoff + 0]; |
|
double y1 = src[srcoff + 1]; |
|
double ctrlx1 = src[srcoff + 2]; |
|
double ctrly1 = src[srcoff + 3]; |
|
double ctrlx2 = src[srcoff + 4]; |
|
double ctrly2 = src[srcoff + 5]; |
|
double x2 = src[srcoff + 6]; |
|
double y2 = src[srcoff + 7]; |
|
if (left != null) { |
|
left[leftoff + 0] = x1; |
|
left[leftoff + 1] = y1; |
|
} |
|
if (right != null) { |
|
right[rightoff + 6] = x2; |
|
right[rightoff + 7] = y2; |
|
} |
|
x1 = (x1 + ctrlx1) / 2.0; |
|
y1 = (y1 + ctrly1) / 2.0; |
|
x2 = (x2 + ctrlx2) / 2.0; |
|
y2 = (y2 + ctrly2) / 2.0; |
|
double centerx = (ctrlx1 + ctrlx2) / 2.0; |
|
double centery = (ctrly1 + ctrly2) / 2.0; |
|
ctrlx1 = (x1 + centerx) / 2.0; |
|
ctrly1 = (y1 + centery) / 2.0; |
|
ctrlx2 = (x2 + centerx) / 2.0; |
|
ctrly2 = (y2 + centery) / 2.0; |
|
centerx = (ctrlx1 + ctrlx2) / 2.0; |
|
centery = (ctrly1 + ctrly2) / 2.0; |
|
if (left != null) { |
|
left[leftoff + 2] = x1; |
|
left[leftoff + 3] = y1; |
|
left[leftoff + 4] = ctrlx1; |
|
left[leftoff + 5] = ctrly1; |
|
left[leftoff + 6] = centerx; |
|
left[leftoff + 7] = centery; |
|
} |
|
if (right != null) { |
|
right[rightoff + 0] = centerx; |
|
right[rightoff + 1] = centery; |
|
right[rightoff + 2] = ctrlx2; |
|
right[rightoff + 3] = ctrly2; |
|
right[rightoff + 4] = x2; |
|
right[rightoff + 5] = y2; |
|
} |
|
} |
|
/** |
|
* Solves the cubic whose coefficients are in the <code>eqn</code> |
|
* array and places the non-complex roots back into the same array, |
|
* returning the number of roots. The solved cubic is represented |
|
* by the equation: |
|
* <pre> |
|
* eqn = {c, b, a, d} |
|
* dx^3 + ax^2 + bx + c = 0 |
|
* </pre> |
|
* A return value of -1 is used to distinguish a constant equation |
|
* that might be always 0 or never 0 from an equation that has no |
|
* zeroes. |
|
* @param eqn an array containing coefficients for a cubic |
|
* @return the number of roots, or -1 if the equation is a constant. |
|
* @since 1.2 |
|
*/ |
|
public static int solveCubic(double eqn[]) { |
|
return solveCubic(eqn, eqn); |
|
} |
|
/** |
|
* Solve the cubic whose coefficients are in the <code>eqn</code> |
|
* array and place the non-complex roots into the <code>res</code> |
|
* array, returning the number of roots. |
|
* The cubic solved is represented by the equation: |
|
* eqn = {c, b, a, d} |
|
* dx^3 + ax^2 + bx + c = 0 |
|
* A return value of -1 is used to distinguish a constant equation, |
|
* which may be always 0 or never 0, from an equation which has no |
|
* zeroes. |
|
* @param eqn the specified array of coefficients to use to solve |
|
* the cubic equation |
|
* @param res the array that contains the non-complex roots |
|
* resulting from the solution of the cubic equation |
|
* @return the number of roots, or -1 if the equation is a constant |
|
* @since 1.3 |
|
*/ |
|
public static int solveCubic(double eqn[], double res[]) { |
|
// From Graphics Gems: |
|
// http://tog.acm.org/resources/GraphicsGems/gems/Roots3And4.c |
|
final double d = eqn[3]; |
|
if (d == 0) { |
|
return QuadCurve2D.solveQuadratic(eqn, res); |
|
} |
|
/* normal form: x^3 + Ax^2 + Bx + C = 0 */ |
|
final double A = eqn[2] / d; |
|
final double B = eqn[1] / d; |
|
final double C = eqn[0] / d; |
|
// substitute x = y - A/3 to eliminate quadratic term: |
|
// x^3 +Px + Q = 0 |
|
// |
|
// Since we actually need P/3 and Q/2 for all of the |
|
// calculations that follow, we will calculate |
|
// p = P/3 |
|
// q = Q/2 |
|
// instead and use those values for simplicity of the code. |
|
double sq_A = A * A; |
|
double p = 1.0/3 * (-1.0/3 * sq_A + B); |
|
double q = 1.0/2 * (2.0/27 * A * sq_A - 1.0/3 * A * B + C); |
|
/* use Cardano's formula */ |
|
double cb_p = p * p * p; |
|
double D = q * q + cb_p; |
|
final double sub = 1.0/3 * A; |
|
int num; |
|
if (D < 0) { /* Casus irreducibilis: three real solutions */ |
|
// see: http://en.wikipedia.org/wiki/Cubic_function#Trigonometric_.28and_hyperbolic.29_method |
|
double phi = 1.0/3 * Math.acos(-q / Math.sqrt(-cb_p)); |
|
double t = 2 * Math.sqrt(-p); |
|
if (res == eqn) { |
|
eqn = Arrays.copyOf(eqn, 4); |
|
} |
|
res[ 0 ] = ( t * Math.cos(phi)); |
|
res[ 1 ] = (-t * Math.cos(phi + Math.PI / 3)); |
|
res[ 2 ] = (-t * Math.cos(phi - Math.PI / 3)); |
|
num = 3; |
|
for (int i = 0; i < num; ++i) { |
|
res[ i ] -= sub; |
|
} |
|
} else { |
|
// Please see the comment in fixRoots marked 'XXX' before changing |
|
// any of the code in this case. |
|
double sqrt_D = Math.sqrt(D); |
|
double u = Math.cbrt(sqrt_D - q); |
|
double v = - Math.cbrt(sqrt_D + q); |
|
double uv = u+v; |
|
num = 1; |
|
double err = 1200000000*ulp(abs(uv) + abs(sub)); |
|
if (iszero(D, err) || within(u, v, err)) { |
|
if (res == eqn) { |
|
eqn = Arrays.copyOf(eqn, 4); |
|
} |
|
res[1] = -(uv / 2) - sub; |
|
num = 2; |
|
} |
|
// this must be done after the potential Arrays.copyOf |
|
res[ 0 ] = uv - sub; |
|
} |
|
if (num > 1) { // num == 3 || num == 2 |
|
num = fixRoots(eqn, res, num); |
|
} |
|
if (num > 2 && (res[2] == res[1] || res[2] == res[0])) { |
|
num--; |
|
} |
|
if (num > 1 && res[1] == res[0]) { |
|
res[1] = res[--num]; // Copies res[2] to res[1] if needed |
|
} |
|
return num; |
|
} |
|
// preconditions: eqn != res && eqn[3] != 0 && num > 1 |
|
// This method tries to improve the accuracy of the roots of eqn (which |
|
// should be in res). It also might eliminate roots in res if it decideds |
|
// that they're not real roots. It will not check for roots that the |
|
// computation of res might have missed, so this method should only be |
|
// used when the roots in res have been computed using an algorithm |
|
// that never underestimates the number of roots (such as solveCubic above) |
|
private static int fixRoots(double[] eqn, double[] res, int num) { |
|
double[] intervals = {eqn[1], 2*eqn[2], 3*eqn[3]}; |
|
int critCount = QuadCurve2D.solveQuadratic(intervals, intervals); |
|
if (critCount == 2 && intervals[0] == intervals[1]) { |
|
critCount--; |
|
} |
|
if (critCount == 2 && intervals[0] > intervals[1]) { |
|
double tmp = intervals[0]; |
|
intervals[0] = intervals[1]; |
|
intervals[1] = tmp; |
|
} |
|
// below we use critCount to possibly filter out roots that shouldn't |
|
// have been computed. We require that eqn[3] != 0, so eqn is a proper |
|
// cubic, which means that its limits at -/+inf are -/+inf or +/-inf. |
|
// Therefore, if critCount==2, the curve is shaped like a sideways S, |
|
// and it could have 1-3 roots. If critCount==0 it is monotonic, and |
|
// if critCount==1 it is monotonic with a single point where it is |
|
// flat. In the last 2 cases there can only be 1 root. So in cases |
|
// where num > 1 but critCount < 2, we eliminate all roots in res |
|
// except one. |
|
if (num == 3) { |
|
double xe = getRootUpperBound(eqn); |
|
double x0 = -xe; |
|
Arrays.sort(res, 0, num); |
|
if (critCount == 2) { |
|
// this just tries to improve the accuracy of the computed |
|
// roots using Newton's method. |
|
res[0] = refineRootWithHint(eqn, x0, intervals[0], res[0]); |
|
res[1] = refineRootWithHint(eqn, intervals[0], intervals[1], res[1]); |
|
res[2] = refineRootWithHint(eqn, intervals[1], xe, res[2]); |
|
return 3; |
|
} else if (critCount == 1) { |
|
// we only need fx0 and fxe for the sign of the polynomial |
|
// at -inf and +inf respectively, so we don't need to do |
|
// fx0 = solveEqn(eqn, 3, x0); fxe = solveEqn(eqn, 3, xe) |
|
double fxe = eqn[3]; |
|
double fx0 = -fxe; |
|
double x1 = intervals[0]; |
|
double fx1 = solveEqn(eqn, 3, x1); |
|
// if critCount == 1 or critCount == 0, but num == 3 then |
|
// something has gone wrong. This branch and the one below |
|
// would ideally never execute, but if they do we can't know |
|
// which of the computed roots is closest to the real root; |
|
// therefore, we can't use refineRootWithHint. But even if |
|
// we did know, being here most likely means that the |
|
// curve is very flat close to two of the computed roots |
|
// (or maybe even all three). This might make Newton's method |
|
// fail altogether, which would be a pain to detect and fix. |
|
// This is why we use a very stable bisection method. |
|
if (oppositeSigns(fx0, fx1)) { |
|
res[0] = bisectRootWithHint(eqn, x0, x1, res[0]); |
|
} else if (oppositeSigns(fx1, fxe)) { |
|
res[0] = bisectRootWithHint(eqn, x1, xe, res[2]); |
|
} else /* fx1 must be 0 */ { |
|
res[0] = x1; |
|
} |
|
// return 1 |
|
} else if (critCount == 0) { |
|
res[0] = bisectRootWithHint(eqn, x0, xe, res[1]); |
|
// return 1 |
|
} |
|
} else if (num == 2 && critCount == 2) { |
|
// XXX: here we assume that res[0] has better accuracy than res[1]. |
|
// This is true because this method is only used from solveCubic |
|
// which puts in res[0] the root that it would compute anyway even |
|
// if num==1. If this method is ever used from any other method, or |
|
// if the solveCubic implementation changes, this assumption should |
|
// be reevaluated, and the choice of goodRoot might have to become |
|
// goodRoot = (abs(eqn'(res[0])) > abs(eqn'(res[1]))) ? res[0] : res[1] |
|
// where eqn' is the derivative of eqn. |
|
double goodRoot = res[0]; |
|
double badRoot = res[1]; |
|
double x1 = intervals[0]; |
|
double x2 = intervals[1]; |
|
// If a cubic curve really has 2 roots, one of those roots must be |
|
// at a critical point. That can't be goodRoot, so we compute x to |
|
// be the farthest critical point from goodRoot. If there are two |
|
// roots, x must be the second one, so we evaluate eqn at x, and if |
|
// it is zero (or close enough) we put x in res[1] (or badRoot, if |
|
// |solveEqn(eqn, 3, badRoot)| < |solveEqn(eqn, 3, x)| but this |
|
// shouldn't happen often). |
|
double x = abs(x1 - goodRoot) > abs(x2 - goodRoot) ? x1 : x2; |
|
double fx = solveEqn(eqn, 3, x); |
|
if (iszero(fx, 10000000*ulp(x))) { |
|
double badRootVal = solveEqn(eqn, 3, badRoot); |
|
res[1] = abs(badRootVal) < abs(fx) ? badRoot : x; |
|
return 2; |
|
} |
|
} // else there can only be one root - goodRoot, and it is already in res[0] |
|
return 1; |
|
} |
|
// use newton's method. |
|
private static double refineRootWithHint(double[] eqn, double min, double max, double t) { |
|
if (!inInterval(t, min, max)) { |
|
return t; |
|
} |
|
double[] deriv = {eqn[1], 2*eqn[2], 3*eqn[3]}; |
|
double origt = t; |
|
for (int i = 0; i < 3; i++) { |
|
double slope = solveEqn(deriv, 2, t); |
|
double y = solveEqn(eqn, 3, t); |
|
double delta = - (y / slope); |
|
double newt = t + delta; |
|
if (slope == 0 || y == 0 || t == newt) { |
|
break; |
|
} |
|
t = newt; |
|
} |
|
if (within(t, origt, 1000*ulp(origt)) && inInterval(t, min, max)) { |
|
return t; |
|
} |
|
return origt; |
|
} |
|
private static double bisectRootWithHint(double[] eqn, double x0, double xe, double hint) { |
|
double delta1 = Math.min(abs(hint - x0) / 64, 0.0625); |
|
double delta2 = Math.min(abs(hint - xe) / 64, 0.0625); |
|
double x02 = hint - delta1; |
|
double xe2 = hint + delta2; |
|
double fx02 = solveEqn(eqn, 3, x02); |
|
double fxe2 = solveEqn(eqn, 3, xe2); |
|
while (oppositeSigns(fx02, fxe2)) { |
|
if (x02 >= xe2) { |
|
return x02; |
|
} |
|
x0 = x02; |
|
xe = xe2; |
|
delta1 /= 64; |
|
delta2 /= 64; |
|
x02 = hint - delta1; |
|
xe2 = hint + delta2; |
|
fx02 = solveEqn(eqn, 3, x02); |
|
fxe2 = solveEqn(eqn, 3, xe2); |
|
} |
|
if (fx02 == 0) { |
|
return x02; |
|
} |
|
if (fxe2 == 0) { |
|
return xe2; |
|
} |
|
return bisectRoot(eqn, x0, xe); |
|
} |
|
private static double bisectRoot(double[] eqn, double x0, double xe) { |
|
double fx0 = solveEqn(eqn, 3, x0); |
|
double m = x0 + (xe - x0) / 2; |
|
while (m != x0 && m != xe) { |
|
double fm = solveEqn(eqn, 3, m); |
|
if (fm == 0) { |
|
return m; |
|
} |
|
if (oppositeSigns(fx0, fm)) { |
|
xe = m; |
|
} else { |
|
fx0 = fm; |
|
x0 = m; |
|
} |
|
m = x0 + (xe-x0)/2; |
|
} |
|
return m; |
|
} |
|
private static boolean inInterval(double t, double min, double max) { |
|
return min <= t && t <= max; |
|
} |
|
private static boolean within(double x, double y, double err) { |
|
double d = y - x; |
|
return (d <= err && d >= -err); |
|
} |
|
private static boolean iszero(double x, double err) { |
|
return within(x, 0, err); |
|
} |
|
private static boolean oppositeSigns(double x1, double x2) { |
|
return (x1 < 0 && x2 > 0) || (x1 > 0 && x2 < 0); |
|
} |
|
private static double solveEqn(double eqn[], int order, double t) { |
|
double v = eqn[order]; |
|
while (--order >= 0) { |
|
v = v * t + eqn[order]; |
|
} |
|
return v; |
|
} |
|
/* |
|
* Computes M+1 where M is an upper bound for all the roots in of eqn. |
|
* See: http://en.wikipedia.org/wiki/Sturm%27s_theorem#Applications. |
|
* The above link doesn't contain a proof, but I [dlila] proved it myself |
|
* so the result is reliable. The proof isn't difficult, but it's a bit |
|
* long to include here. |
|
* Precondition: eqn must represent a cubic polynomial |
|
*/ |
|
private static double getRootUpperBound(double[] eqn) { |
|
double d = eqn[3]; |
|
double a = eqn[2]; |
|
double b = eqn[1]; |
|
double c = eqn[0]; |
|
double M = 1 + max(max(abs(a), abs(b)), abs(c)) / abs(d); |
|
M += ulp(M) + 1; |
|
return M; |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean contains(double x, double y) { |
|
if (!(x * 0.0 + y * 0.0 == 0.0)) { |
|
/* Either x or y was infinite or NaN. |
|
* A NaN always produces a negative response to any test |
|
* and Infinity values cannot be "inside" any path so |
|
* they should return false as well. |
|
*/ |
|
return false; |
|
} |
|
// We count the "Y" crossings to determine if the point is |
|
// inside the curve bounded by its closing line. |
|
double x1 = getX1(); |
|
double y1 = getY1(); |
|
double x2 = getX2(); |
|
double y2 = getY2(); |
|
int crossings = |
|
(Curve.pointCrossingsForLine(x, y, x1, y1, x2, y2) + |
|
Curve.pointCrossingsForCubic(x, y, |
|
x1, y1, |
|
getCtrlX1(), getCtrlY1(), |
|
getCtrlX2(), getCtrlY2(), |
|
x2, y2, 0)); |
|
return ((crossings & 1) == 1); |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean contains(Point2D p) { |
|
return contains(p.getX(), p.getY()); |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean intersects(double x, double y, double w, double h) { |
|
// Trivially reject non-existant rectangles |
|
if (w <= 0 || h <= 0) { |
|
return false; |
|
} |
|
int numCrossings = rectCrossings(x, y, w, h); |
|
// the intended return value is |
|
// numCrossings != 0 || numCrossings == Curve.RECT_INTERSECTS |
|
// but if (numCrossings != 0) numCrossings == INTERSECTS won't matter |
|
// and if !(numCrossings != 0) then numCrossings == 0, so |
|
// numCrossings != RECT_INTERSECT |
|
return numCrossings != 0; |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean intersects(Rectangle2D r) { |
|
return intersects(r.getX(), r.getY(), r.getWidth(), r.getHeight()); |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean contains(double x, double y, double w, double h) { |
|
if (w <= 0 || h <= 0) { |
|
return false; |
|
} |
|
int numCrossings = rectCrossings(x, y, w, h); |
|
return !(numCrossings == 0 || numCrossings == Curve.RECT_INTERSECTS); |
|
} |
|
private int rectCrossings(double x, double y, double w, double h) { |
|
int crossings = 0; |
|
if (!(getX1() == getX2() && getY1() == getY2())) { |
|
crossings = Curve.rectCrossingsForLine(crossings, |
|
x, y, |
|
x+w, y+h, |
|
getX1(), getY1(), |
|
getX2(), getY2()); |
|
if (crossings == Curve.RECT_INTERSECTS) { |
|
return crossings; |
|
} |
|
} |
|
// we call this with the curve's direction reversed, because we wanted |
|
// to call rectCrossingsForLine first, because it's cheaper. |
|
return Curve.rectCrossingsForCubic(crossings, |
|
x, y, |
|
x+w, y+h, |
|
getX2(), getY2(), |
|
getCtrlX2(), getCtrlY2(), |
|
getCtrlX1(), getCtrlY1(), |
|
getX1(), getY1(), 0); |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public boolean contains(Rectangle2D r) { |
|
return contains(r.getX(), r.getY(), r.getWidth(), r.getHeight()); |
|
} |
|
/** |
|
* {@inheritDoc} |
|
* @since 1.2 |
|
*/ |
|
public Rectangle getBounds() { |
|
return getBounds2D().getBounds(); |
|
} |
|
/** |
|
* Returns an iteration object that defines the boundary of the |
|
* shape. |
|
* The iterator for this class is not multi-threaded safe, |
|
* which means that this <code>CubicCurve2D</code> class does not |
|
* guarantee that modifications to the geometry of this |
|
* <code>CubicCurve2D</code> object do not affect any iterations of |
|
* that geometry that are already in process. |
|
* @param at an optional <code>AffineTransform</code> to be applied to the |
|
* coordinates as they are returned in the iteration, or <code>null</code> |
|
* if untransformed coordinates are desired |
|
* @return the <code>PathIterator</code> object that returns the |
|
* geometry of the outline of this <code>CubicCurve2D</code>, one |
|
* segment at a time. |
|
* @since 1.2 |
|
*/ |
|
public PathIterator getPathIterator(AffineTransform at) { |
|
return new CubicIterator(this, at); |
|
} |
|
/** |
|
* Return an iteration object that defines the boundary of the |
|
* flattened shape. |
|
* The iterator for this class is not multi-threaded safe, |
|
* which means that this <code>CubicCurve2D</code> class does not |
|
* guarantee that modifications to the geometry of this |
|
* <code>CubicCurve2D</code> object do not affect any iterations of |
|
* that geometry that are already in process. |
|
* @param at an optional <code>AffineTransform</code> to be applied to the |
|
* coordinates as they are returned in the iteration, or <code>null</code> |
|
* 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 end points |
|
* @return the <code>PathIterator</code> object that returns the |
|
* geometry of the outline of this <code>CubicCurve2D</code>, |
|
* one segment at a time. |
|
* @since 1.2 |
|
*/ |
|
public PathIterator getPathIterator(AffineTransform at, double flatness) { |
|
return new FlatteningPathIterator(getPathIterator(at), flatness); |
|
} |
|
/** |
|
* Creates a new object of the same class as this object. |
|
* |
|
* @return a clone of this instance. |
|
* @exception OutOfMemoryError if there is not enough memory. |
|
* @see java.lang.Cloneable |
|
* @since 1.2 |
|
*/ |
|
public Object clone() { |
|
try { |
|
return super.clone(); |
|
} catch (CloneNotSupportedException e) { |
|
// this shouldn't happen, since we are Cloneable |
|
throw new InternalError(e); |
|
} |
|
} |
|
} |