001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ---------------------------
028 * CategoryCrosshairState.java
029 * ---------------------------
030 * (C) Copyright 2008, by Object Refinery Limited and Contributors.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes
036 * -------
037 * 26-Jun-2008 : Version 1 (DG);
038 *
039 */
040
041package org.jfree.chart.plot;
042
043import java.awt.geom.Point2D;
044
045import org.jfree.chart.renderer.category.CategoryItemRenderer;
046
047/**
048 * Represents state information for the crosshairs in a {@link CategoryPlot}.
049 * An instance of this class is created at the start of the rendering process,
050 * and updated as each data item is rendered.  At the end of the rendering
051 * process, this class holds the row key, column key and value for the
052 * crosshair location.
053 *
054 * @since 1.0.11
055 */
056public class CategoryCrosshairState extends CrosshairState {
057
058    /**
059     * The row key for the crosshair point.
060     */
061    private Comparable rowKey;
062
063    /**
064     * The column key for the crosshair point.
065     */
066    private Comparable columnKey;
067
068    /**
069     * Creates a new instance.
070     */
071    public CategoryCrosshairState() {
072        this.rowKey = null;
073        this.columnKey = null;
074    }
075
076    /**
077     * Returns the row key.
078     *
079     * @return The row key.
080     */
081    public Comparable getRowKey() {
082        return this.rowKey;
083    }
084
085    /**
086     * Sets the row key.
087     *
088     * @param key  the row key.
089     */
090    public void setRowKey(Comparable key) {
091        this.rowKey = key;
092    }
093
094    /**
095     * Returns the column key.
096     *
097     * @return The column key.
098     */
099    public Comparable getColumnKey() {
100        return this.columnKey;
101    }
102
103    /**
104     * Sets the column key.
105     *
106     * @param key  the key.
107     */
108    public void setColumnKey(Comparable key) {
109        this.columnKey = key;
110    }
111
112    /**
113     * Evaluates a data point from a {@link CategoryItemRenderer} and if it is
114     * the closest to the anchor point it becomes the new crosshair point.
115     *
116     * @param rowKey  the row key.
117     * @param columnKey  the column key.
118     * @param value  y coordinate (measured against the range axis).
119     * @param datasetIndex  the dataset index for this point.
120     * @param transX  x translated into Java2D space.
121     * @param transY  y translated into Java2D space.
122     * @param orientation  the plot orientation.
123     */
124    public void updateCrosshairPoint(Comparable rowKey, Comparable columnKey,
125            double value, int datasetIndex, double transX, double transY,
126            PlotOrientation orientation) {
127
128        Point2D anchor = getAnchor();
129        if (anchor != null) {
130            double xx = anchor.getX();
131            double yy = anchor.getY();
132            if (orientation == PlotOrientation.HORIZONTAL) {
133                double temp = yy;
134                yy = xx;
135                xx = temp;
136            }
137            double d = (transX - xx) * (transX - xx)
138                    + (transY - yy) * (transY - yy);
139
140            if (d < getCrosshairDistance()) {
141                this.rowKey = rowKey;
142                this.columnKey = columnKey;
143                setCrosshairY(value);
144                setDatasetIndex(datasetIndex);
145                setCrosshairDistance(d);
146            }
147        }
148
149    }
150
151    /**
152     * Updates only the crosshair row and column keys (this is for the case
153     * where the range crosshair does NOT lock onto the nearest data value).
154     *
155     * @param rowKey  the row key.
156     * @param columnKey  the column key.
157     * @param datasetIndex  the dataset axis index.
158     * @param transX  the translated x-value.
159     * @param orientation  the plot orientation.
160     */
161    public void updateCrosshairX(Comparable rowKey, Comparable columnKey,
162            int datasetIndex, double transX, PlotOrientation orientation) {
163
164        Point2D anchor = getAnchor();
165        if (anchor != null) {
166            double anchorX = anchor.getX();
167            if (orientation == PlotOrientation.HORIZONTAL) {
168                anchorX = anchor.getY();
169            }
170            double d = Math.abs(transX - anchorX);
171            if (d < getCrosshairDistance()) {
172                this.rowKey = rowKey;
173                this.columnKey = columnKey;
174                setDatasetIndex(datasetIndex);
175                setCrosshairDistance(d);
176            }
177        }
178
179    }
180
181}