org.jfree.chart.renderer.xy.XYSplineRenderer Maven / Gradle / Ivy
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/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2014, 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.]
*
* ---------------------
* XYSplineRenderer.java
* ---------------------
* (C) Copyright 2007-2014, by Klaus Rheinwald and Contributors.
*
* Original Author: Klaus Rheinwald;
* Contributor(s): Tobias von Petersdorff ([email protected],
* http://www.wam.umd.edu/~petersd/);
* David Gilbert (for Object Refinery Limited);
*
* Changes:
* --------
* 25-Jul-2007 : Version 1, contributed by Klaus Rheinwald (DG);
* 03-Aug-2007 : Added new constructor (KR);
* 25-Oct-2007 : Prevent duplicate control points (KR);
* 19-May-2009 : Fixed FindBugs warnings, patch by Michal Wozniak (DG);
* 14-Sep-2013 : Replaced Vector with List, general cleanup (KR);
* 15-Sep-2013 : Added support to fill the area 'under' (between '0' and) the
* spline(KR);
* 15-Sep-2013 : Replaced ControlPoint with Point2D.Float (KR);
*
*/
package org.jfree.chart.renderer.xy;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.geom.GeneralPath;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.List;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.event.RendererChangeEvent;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.util.ParamChecks;
import org.jfree.data.xy.XYDataset;
import org.jfree.ui.GradientPaintTransformer;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.StandardGradientPaintTransformer;
import org.jfree.util.ObjectUtilities;
/**
* A renderer that connects data points with natural cubic splines and/or
* draws shapes at each data point. This renderer is designed for use with
* the {@link XYPlot} class. The example shown here is generated by the
* XYSplineRendererDemo1.java program included in the JFreeChart
* demo collection:
*
* 
*
* @since 1.0.7
*/
public class XYSplineRenderer extends XYLineAndShapeRenderer {
/**
* An enumeration of the fill types for the renderer.
*
* @since 1.0.17
*/
public static enum FillType {
NONE,
TO_ZERO,
TO_LOWER_BOUND,
TO_UPPER_BOUND
}
/**
* Represents state information that applies to a single rendering of
* a chart.
*/
public static class XYSplineState extends State {
/** The area to fill under the curve. */
public GeneralPath fillArea;
/** The points. */
public List points;
/**
* Creates a new state instance.
*
* @param info the plot rendering info.
*/
public XYSplineState(PlotRenderingInfo info) {
super(info);
this.fillArea = new GeneralPath();
this.points = new ArrayList();
}
}
/**
* Resolution of splines (number of line segments between points)
*/
private int precision;
/**
* A flag that can be set to specify
* to fill the area under the spline.
*/
private FillType fillType;
private GradientPaintTransformer gradientPaintTransformer;
/**
* Creates a new instance with the precision attribute defaulting to 5
* and no fill of the area 'under' the spline.
*/
public XYSplineRenderer() {
this(5, FillType.NONE);
}
/**
* Creates a new renderer with the specified precision
* and no fill of the area 'under' (between '0' and) the spline.
*
* @param precision the number of points between data items.
*/
public XYSplineRenderer(int precision) {
this(precision, FillType.NONE);
}
/**
* Creates a new renderer with the specified precision
* and specified fill of the area 'under' (between '0' and) the spline.
*
* @param precision the number of points between data items.
* @param fillType the type of fill beneath the curve (null
* not permitted).
*
* @since 1.0.17
*/
public XYSplineRenderer(int precision, FillType fillType) {
super();
if (precision <= 0) {
throw new IllegalArgumentException("Requires precision > 0.");
}
ParamChecks.nullNotPermitted(fillType, "fillType");
this.precision = precision;
this.fillType = fillType;
this.gradientPaintTransformer = new StandardGradientPaintTransformer();
}
/**
* Returns the number of line segments used to approximate the spline
* curve between data points.
*
* @return The number of line segments.
*
* @see #setPrecision(int)
*/
public int getPrecision() {
return this.precision;
}
/**
* Set the resolution of splines and sends a {@link RendererChangeEvent}
* to all registered listeners.
*
* @param p number of line segments between points (must be > 0).
*
* @see #getPrecision()
*/
public void setPrecision(int p) {
if (p <= 0) {
throw new IllegalArgumentException("Requires p > 0.");
}
this.precision = p;
fireChangeEvent();
}
/**
* Returns the type of fill that the renderer draws beneath the curve.
*
* @return The type of fill (never null).
*
* @see #setFillType(FillType)
*
* @since 1.0.17
*/
public FillType getFillType() {
return this.fillType;
}
/**
* Set the fill type and sends a {@link RendererChangeEvent}
* to all registered listeners.
*
* @param fillType the fill type (null not permitted).
*
* @see #getFillType()
*
* @since 1.0.17
*/
public void setFillType(FillType fillType) {
this.fillType = fillType;
fireChangeEvent();
}
/**
* Returns the gradient paint transformer, or null.
*
* @return The gradient paint transformer (possibly null).
*
* @since 1.0.17
*/
public GradientPaintTransformer getGradientPaintTransformer() {
return this.gradientPaintTransformer;
}
/**
* Sets the gradient paint transformer and sends a
* {@link RendererChangeEvent} to all registered listeners.
*
* @param gpt the transformer (null permitted).
*
* @since 1.0.17
*/
public void setGradientPaintTransformer(GradientPaintTransformer gpt) {
this.gradientPaintTransformer = gpt;
fireChangeEvent();
}
/**
* 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) {
setDrawSeriesLineAsPath(true);
XYSplineState state = new XYSplineState(info);
state.setProcessVisibleItemsOnly(false);
return state;
}
/**
* Draws the item (first pass). This method draws the lines
* connecting the items. Instead of drawing separate lines,
* a GeneralPath is constructed and drawn at the end of
* the series painting.
*
* @param g2 the graphics device.
* @param state the renderer state.
* @param plot the plot (can be used to obtain standard color information
* etc).
* @param dataset the dataset.
* @param pass the pass.
* @param series the series index (zero-based).
* @param item the item index (zero-based).
* @param xAxis the domain axis.
* @param yAxis the range axis.
* @param dataArea the area within which the data is being drawn.
*/
@Override
protected void drawPrimaryLineAsPath(XYItemRendererState state,
Graphics2D g2, XYPlot plot, XYDataset dataset, int pass,
int series, int item, ValueAxis xAxis, ValueAxis yAxis,
Rectangle2D dataArea) {
XYSplineState s = (XYSplineState) state;
RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
// get the data points
double x1 = dataset.getXValue(series, item);
double y1 = dataset.getYValue(series, item);
double transX1 = xAxis.valueToJava2D(x1, dataArea, xAxisLocation);
double transY1 = yAxis.valueToJava2D(y1, dataArea, yAxisLocation);
// Collect points
if (!Double.isNaN(transX1) && !Double.isNaN(transY1)) {
Point2D p = plot.getOrientation() == PlotOrientation.HORIZONTAL
? new Point2D.Float((float) transY1, (float) transX1)
: new Point2D.Float((float) transX1, (float) transY1);
if (!s.points.contains(p))
s.points.add(p);
}
if (item == dataset.getItemCount(series) - 1) { // construct path
if (s.points.size() > 1) {
Point2D origin;
if (this.fillType == FillType.TO_ZERO) {
float xz = (float) xAxis.valueToJava2D(0, dataArea,
yAxisLocation);
float yz = (float) yAxis.valueToJava2D(0, dataArea,
yAxisLocation);
origin = plot.getOrientation() == PlotOrientation.HORIZONTAL
? new Point2D.Float(yz, xz)
: new Point2D.Float(xz, yz);
} else if (this.fillType == FillType.TO_LOWER_BOUND) {
float xlb = (float) xAxis.valueToJava2D(
xAxis.getLowerBound(), dataArea, xAxisLocation);
float ylb = (float) yAxis.valueToJava2D(
yAxis.getLowerBound(), dataArea, yAxisLocation);
origin = plot.getOrientation() == PlotOrientation.HORIZONTAL
? new Point2D.Float(ylb, xlb)
: new Point2D.Float(xlb, ylb);
} else {// fillType == TO_UPPER_BOUND
float xub = (float) xAxis.valueToJava2D(
xAxis.getUpperBound(), dataArea, xAxisLocation);
float yub = (float) yAxis.valueToJava2D(
yAxis.getUpperBound(), dataArea, yAxisLocation);
origin = plot.getOrientation() == PlotOrientation.HORIZONTAL
? new Point2D.Float(yub, xub)
: new Point2D.Float(xub, yub);
}
// we need at least two points to draw something
Point2D cp0 = s.points.get(0);
s.seriesPath.moveTo(cp0.getX(), cp0.getY());
if (this.fillType != FillType.NONE) {
if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
s.fillArea.moveTo(origin.getX(), cp0.getY());
} else {
s.fillArea.moveTo(cp0.getX(), origin.getY());
}
s.fillArea.lineTo(cp0.getX(), cp0.getY());
}
if (s.points.size() == 2) {
// we need at least 3 points to spline. Draw simple line
// for two points
Point2D cp1 = s.points.get(1);
if (this.fillType != FillType.NONE) {
s.fillArea.lineTo(cp1.getX(), cp1.getY());
s.fillArea.lineTo(cp1.getX(), origin.getY());
s.fillArea.closePath();
}
s.seriesPath.lineTo(cp1.getX(), cp1.getY());
} else {
// construct spline
int np = s.points.size(); // number of points
float[] d = new float[np]; // Newton form coefficients
float[] x = new float[np]; // x-coordinates of nodes
float y, oldy;
float t, oldt;
float[] a = new float[np];
float t1;
float t2;
float[] h = new float[np];
for (int i = 0; i < np; i++) {
Point2D.Float cpi = (Point2D.Float) s.points.get(i);
x[i] = cpi.x;
d[i] = cpi.y;
}
for (int i = 1; i <= np - 1; i++)
h[i] = x[i] - x[i - 1];
float[] sub = new float[np - 1];
float[] diag = new float[np - 1];
float[] sup = new float[np - 1];
for (int i = 1; i <= np - 2; i++) {
diag[i] = (h[i] + h[i + 1]) / 3;
sup[i] = h[i + 1] / 6;
sub[i] = h[i] / 6;
a[i] = (d[i + 1] - d[i]) / h[i + 1]
- (d[i] - d[i - 1]) / h[i];
}
solveTridiag(sub, diag, sup, a, np - 2);
// note that a[0]=a[np-1]=0
oldt = x[0];
oldy = d[0];
for (int i = 1; i <= np - 1; i++) {
// loop over intervals between nodes
for (int j = 1; j <= this.precision; j++) {
t1 = (h[i] * j) / this.precision;
t2 = h[i] - t1;
y = ((-a[i - 1] / 6 * (t2 + h[i]) * t1 + d[i - 1])
* t2 + (-a[i] / 6 * (t1 + h[i]) * t2
+ d[i]) * t1) / h[i];
t = x[i - 1] + t1;
s.seriesPath.lineTo(t, y);
if (this.fillType != FillType.NONE) {
s.fillArea.lineTo(t, y);
}
}
}
}
// Add last point @ y=0 for fillPath and close path
if (this.fillType != FillType.NONE) {
if (plot.getOrientation() == PlotOrientation.HORIZONTAL) {
s.fillArea.lineTo(origin.getX(), s.points.get(
s.points.size() - 1).getY());
} else {
s.fillArea.lineTo(s.points.get(
s.points.size() - 1).getX(), origin.getY());
}
s.fillArea.closePath();
}
// fill under the curve...
if (this.fillType != FillType.NONE) {
Paint fp = getSeriesFillPaint(series);
if (this.gradientPaintTransformer != null
&& fp instanceof GradientPaint) {
GradientPaint gp = this.gradientPaintTransformer
.transform((GradientPaint) fp, s.fillArea);
g2.setPaint(gp);
} else {
g2.setPaint(fp);
}
g2.fill(s.fillArea);
s.fillArea.reset();
}
// then draw the line...
drawFirstPassShape(g2, pass, series, item, s.seriesPath);
}
// reset points vector
s.points = new ArrayList();
}
}
private void solveTridiag(float[] sub, float[] diag, float[] sup,
float[] b, int n) {
/* solve linear system with tridiagonal n by n matrix a
using Gaussian elimination *without* pivoting
where a(i,i-1) = sub[i] for 2<=i<=n
a(i,i) = diag[i] for 1<=i<=n
a(i,i+1) = sup[i] for 1<=i<=n-1
(the values sub[1], sup[n] are ignored)
right hand side vector b[1:n] is overwritten with solution
NOTE: 1...n is used in all arrays, 0 is unused */
int i;
/* factorization and forward substitution */
for (i = 2; i <= n; i++) {
sub[i] /= diag[i - 1];
diag[i] -= sub[i] * sup[i - 1];
b[i] -= sub[i] * b[i - 1];
}
b[n] /= diag[n];
for (i = n - 1; i >= 1; i--)
b[i] = (b[i] - sup[i] * b[i + 1]) / diag[i];
}
/**
* Tests this renderer for equality with an arbitrary object.
*
* @param obj the object (null permitted).
*
* @return A boolean.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof XYSplineRenderer)) {
return false;
}
XYSplineRenderer that = (XYSplineRenderer) obj;
if (this.precision != that.precision) {
return false;
}
if (this.fillType != that.fillType) {
return false;
}
if (!ObjectUtilities.equal(this.gradientPaintTransformer,
that.gradientPaintTransformer)) {
return false;
}
return super.equals(obj);
}
}