org.jfree.chart.renderer.xy.SamplingXYLineRenderer Maven / Gradle / Ivy
/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2020, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.]
*
* ---------------------------
* SamplingXYLineRenderer.java
* ---------------------------
* (C) Copyright 2008-2016, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited);
* Contributor(s): -;
*/
package org.jfree.chart.renderer.xy;
import java.awt.Graphics2D;
import java.awt.Shape;
import java.awt.geom.GeneralPath;
import java.awt.geom.Line2D;
import java.awt.geom.PathIterator;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.CrosshairState;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.ui.RectangleEdge;
import org.jfree.chart.util.PublicCloneable;
import org.jfree.chart.util.SerialUtils;
import org.jfree.chart.util.ShapeUtils;
import org.jfree.data.xy.XYDataset;
/**
* A renderer that draws line charts. The renderer doesn't necessarily plot
* every data item - instead, it tries to plot only those data items that
* make a difference to the visual output (the other data items are skipped).
* This renderer is designed for use with the {@link XYPlot} class.
*
* @since 1.0.13
*/
public class SamplingXYLineRenderer extends AbstractXYItemRenderer
implements XYItemRenderer, Cloneable, PublicCloneable, Serializable {
/** The shape that is used to represent a line in the legend. */
private transient Shape legendLine;
/**
* Creates a new renderer.
*/
public SamplingXYLineRenderer() {
this.legendLine = new Line2D.Double(-7.0, 0.0, 7.0, 0.0);
setDefaultLegendShape(this.legendLine);
setTreatLegendShapeAsLine(true);
}
/**
* Returns the number of passes through the data that the renderer requires
* in order to draw the chart. Most charts will require a single pass, but
* some require two passes.
*
* @return The pass count.
*/
@Override
public int getPassCount() {
return 1;
}
/**
* Records the state for the renderer. This is used to preserve state
* information between calls to the drawItem() method for a single chart
* drawing.
*/
public static class State extends XYItemRendererState {
/** The path for the current series. */
GeneralPath seriesPath;
/**
* A second path that draws vertical intervals to cover any extreme
* values.
*/
GeneralPath intervalPath;
/**
* The minimum change in the x-value needed to trigger an update to
* the seriesPath.
*/
double dX = 1.0;
/** The last x-coordinate visited by the seriesPath. */
double lastX;
/** The initial y-coordinate for the current x-coordinate. */
double openY = 0.0;
/** The highest y-coordinate for the current x-coordinate. */
double highY = 0.0;
/** The lowest y-coordinate for the current x-coordinate. */
double lowY = 0.0;
/** The final y-coordinate for the current x-coordinate. */
double closeY = 0.0;
/**
* A flag that indicates if the last (x, y) point was 'good'
* (non-null).
*/
boolean lastPointGood;
/**
* Creates a new state instance.
*
* @param info the plot rendering info.
*/
public State(PlotRenderingInfo info) {
super(info);
}
/**
* This method is called by the {@link XYPlot} at the start of each
* series pass. We reset the state for the current series.
*
* @param dataset the dataset.
* @param series the series index.
* @param firstItem the first item index for this pass.
* @param lastItem the last item index for this pass.
* @param pass the current pass index.
* @param passCount the number of passes.
*/
@Override
public void startSeriesPass(XYDataset dataset, int series,
int firstItem, int lastItem, int pass, int passCount) {
this.seriesPath.reset();
this.intervalPath.reset();
this.lastPointGood = false;
super.startSeriesPass(dataset, series, firstItem, lastItem, pass,
passCount);
}
}
/**
* Initialises the renderer.
*
* This method will be called before the first item is rendered, giving the
* renderer an opportunity to initialise any state information it wants to
* maintain. The renderer can do nothing if it chooses.
*
* @param g2 the graphics device.
* @param dataArea the area inside the axes.
* @param plot the plot.
* @param data the data.
* @param info an optional info collection object to return data back to
* the caller.
*
* @return The renderer state.
*/
@Override
public XYItemRendererState initialise(Graphics2D g2,
Rectangle2D dataArea, XYPlot plot, XYDataset data,
PlotRenderingInfo info) {
double dpi = 72;
// Integer dpiVal = (Integer) g2.getRenderingHint(HintKey.DPI);
// if (dpiVal != null) {
// dpi = dpiVal.intValue();
// }
State state = new State(info);
state.seriesPath = new GeneralPath();
state.intervalPath = new GeneralPath();
state.dX = 72.0 / dpi;
return state;
}
/**
* Draws the visual representation of a single data item.
*
* @param g2 the graphics device.
* @param state the renderer state.
* @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 axis.
* @param rangeAxis the range axis.
* @param dataset the dataset.
* @param series the series index (zero-based).
* @param item the item index (zero-based).
* @param crosshairState crosshair information for the plot
* ({@code null} permitted).
* @param pass the pass index.
*/
@Override
public void drawItem(Graphics2D g2, XYItemRendererState state,
Rectangle2D dataArea, PlotRenderingInfo info, XYPlot plot,
ValueAxis domainAxis, ValueAxis rangeAxis, XYDataset dataset,
int series, int item, CrosshairState crosshairState, int pass) {
// do nothing if item is not visible
if (!getItemVisible(series, item)) {
return;
}
RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
// get the data point...
double x1 = dataset.getXValue(series, item);
double y1 = dataset.getYValue(series, item);
double transX1 = domainAxis.valueToJava2D(x1, dataArea, xAxisLocation);
double transY1 = rangeAxis.valueToJava2D(y1, dataArea, yAxisLocation);
State s = (State) state;
// update path to reflect latest point
if (!Double.isNaN(transX1) && !Double.isNaN(transY1)) {
float x = (float) transX1;
float y = (float) transY1;
PlotOrientation orientation = plot.getOrientation();
if (orientation == PlotOrientation.HORIZONTAL) {
x = (float) transY1;
y = (float) transX1;
}
if (s.lastPointGood) {
if ((Math.abs(x - s.lastX) > s.dX)) {
s.seriesPath.lineTo(x, y);
if (s.lowY < s.highY) {
s.intervalPath.moveTo((float) s.lastX, (float) s.lowY);
s.intervalPath.lineTo((float) s.lastX, (float) s.highY);
}
s.lastX = x;
s.openY = y;
s.highY = y;
s.lowY = y;
s.closeY = y;
}
else {
s.highY = Math.max(s.highY, y);
s.lowY = Math.min(s.lowY, y);
s.closeY = y;
}
}
else {
s.seriesPath.moveTo(x, y);
s.lastX = x;
s.openY = y;
s.highY = y;
s.lowY = y;
s.closeY = y;
}
s.lastPointGood = true;
}
else {
s.lastPointGood = false;
}
// if this is the last item, draw the path ...
if (item == s.getLastItemIndex()) {
// draw path
PathIterator pi = s.seriesPath.getPathIterator(null);
int count = 0;
while (!pi.isDone()) {
count++;
pi.next();
}
g2.setStroke(getItemStroke(series, item));
g2.setPaint(getItemPaint(series, item));
g2.draw(s.seriesPath);
g2.draw(s.intervalPath);
}
}
/**
* Returns a clone of the renderer.
*
* @return A clone.
*
* @throws CloneNotSupportedException if the clone cannot be created.
*/
@Override
public Object clone() throws CloneNotSupportedException {
SamplingXYLineRenderer clone = (SamplingXYLineRenderer) super.clone();
if (this.legendLine != null) {
clone.legendLine = ShapeUtils.clone(this.legendLine);
}
return clone;
}
/**
* Tests this renderer for equality with an arbitrary object.
*
* @param obj the object ({@code null} permitted).
*
* @return {@code true} or {@code false}.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof SamplingXYLineRenderer)) {
return false;
}
if (!super.equals(obj)) {
return false;
}
SamplingXYLineRenderer that = (SamplingXYLineRenderer) obj;
if (!ShapeUtils.equal(this.legendLine, that.legendLine)) {
return false;
}
return true;
}
/**
* Provides serialization support.
*
* @param stream the input stream.
*
* @throws IOException if there is an I/O error.
* @throws ClassNotFoundException if there is a classpath problem.
*/
private void readObject(ObjectInputStream stream)
throws IOException, ClassNotFoundException {
stream.defaultReadObject();
this.legendLine = SerialUtils.readShape(stream);
}
/**
* Provides serialization support.
*
* @param stream the output stream.
*
* @throws IOException if there is an I/O error.
*/
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
SerialUtils.writeShape(this.legendLine, stream);
}
}