xydotrenderer.java

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/* ======================================
 * JFreeChart : a free Java chart library
 * ======================================
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 * Project Lead:  David Gilbert ([e-mail]);
 *
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * ------------------
 * XYDotRenderer.java
 * ------------------
 * (C) Copyright 2002, 2003, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   Christian W. Zuckschwerdt;
;
 *
 * $Id: XYDotRenderer.java,v 1.10 2003/07/30 15:51:59 mungady Exp $
 *
 * Changes (from 29-Oct-2002)
 * --------------------------
 * 29-Oct-2002 : Added standard header (DG);
 * 25-Mar-2003 : Implemented Serializable (DG);
 * 01-May-2003 : Modified drawItem(...) method signature (DG);
 * 30-Jul-2003 : Modified entity constructor (CZ);
 * 
 */

package org.jfree.chart.renderer;

import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;

import org.jfree.chart.ChartRenderingInfo;
import org.jfree.chart.CrosshairInfo;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.data.XYDataset;
import org.jfree.ui.RectangleEdge;

/**
 * A renderer that draws a small dot at each data point for an {@link XYPlot}.
 *
 * @author David Gilbert
 */
public class XYDotRenderer extends AbstractXYItemRenderer
                           implements XYItemRenderer, Serializable {

    /**
     * Constructs a new renderer.
     */
    public XYDotRenderer() {

    }

    /**
     * Draws the visual representation of a single data item.
     *
     * @param g2  the graphics device.
     * @param dataArea  the area within which the data is being drawn.
     * @param info  collects information about the drawing.
     * @param plot  the plot (can be used to obtain standard color information etc).
     * @param domainAxis  the domain (horizontal) axis.
     * @param rangeAxis  the range (vertical) axis.
     * @param dataset  the dataset.
     * @param series  the series index (zero-based).
     * @param item  the item index (zero-based).
     * @param crosshairInfo  information about crosshairs on a plot.
     * @param pass  the pass index.
     */
    public void drawItem(Graphics2D g2,
                         Rectangle2D dataArea,
                         ChartRenderingInfo info,
                         XYPlot plot,
                         ValueAxis domainAxis,
                         ValueAxis rangeAxis,
                         XYDataset dataset,
                         int series,
                         int item,
                         CrosshairInfo crosshairInfo,
                         int pass) {

        // get the data point...
        Number xn = dataset.getXValue(series, item);
        Number yn = dataset.getYValue(series, item);
        if (yn != null) {
            double x = xn.doubleValue();
            double y = yn.doubleValue();
            RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
            RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
            double transX = domainAxis.translateValueToJava2D(x, dataArea, xAxisLocation);
            double transY = rangeAxis.translateValueToJava2D(y, dataArea,yAxisLocation);

            g2.setPaint(this.getItemPaint(series, item));
            PlotOrientation orientation = plot.getOrientation();
            if (orientation == PlotOrientation.HORIZONTAL) {
                g2.drawRect((int) transY, (int) transX, 1, 1);
            }
            else if (orientation == PlotOrientation.VERTICAL) {
                g2.drawRect((int) transX, (int) transY, 1, 1);
            }

            // do we need to update the crosshair values?
            if (plot.isDomainCrosshairLockedOnData()) {
                if (plot.isRangeCrosshairLockedOnData()) {
                    // both axes
                    crosshairInfo.updateCrosshairPoint(x, y);
                }
                else {
                    // just the horizontal axis...
                    crosshairInfo.updateCrosshairX(x);
                }
            }
            else {
                if (plot.isRangeCrosshairLockedOnData()) {
                    // just the vertical axis...
                    crosshairInfo.updateCrosshairY(y);
                }
            }
        }

    }

}