/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2011, 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.]
*
* ---------------------------------
* XYSmoothLineAndShapeRenderer.java
* ---------------------------------
* (C) Copyright 2007, by Object Refinery Limited and Contributors.
*
* Original Author: -;
* Contributor(s): -;
*
* Changes
* -------
* 14-Jun-2007 : Version 1;
*
*/
package org.jfree.experimental.chart.renderer.xy;
import java.awt.Graphics2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.entity.EntityCollection;
import org.jfree.chart.plot.CrosshairState;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYItemRendererState;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.xy.XYDataset;
import org.jfree.ui.RectangleEdge;
/**
* A line and shape renderer that performs line smoothing. See
* http://www.jfree.org/phpBB2/viewtopic.php?t=20671
*
* WARNING: THIS CLASS IS NOT PART OF THE STANDARD JFREECHART API AND IS
* SUBJECT TO ALTERATION OR REMOVAL. DO NOT RELY ON THIS CLASS FOR
* PRODUCTION USE. Please experiment with this code and provide feedback.
*/
public class XYSmoothLineAndShapeRenderer extends XYLineAndShapeRenderer {
/**
* Draws the item (first pass). This method draws the lines
* connecting the items.
*
* @param g2 the graphics device.
* @param state the renderer state.
* @param dataArea the area within which the data is being drawn.
* @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 pass the pass.
* @param series the series index (zero-based).
* @param item the item index (zero-based).
*/
protected void drawPrimaryLine(XYItemRendererState state, Graphics2D g2,
XYPlot plot, XYDataset dataset, int pass, int series, int item,
ValueAxis domainAxis, ValueAxis rangeAxis, Rectangle2D dataArea) {
if (item == 0) {
return;
}
// get the data point...
double x1 = dataset.getXValue(series, item);
double y1 = dataset.getYValue(series, item);
if (Double.isNaN(y1) || Double.isNaN(x1)) {
return;
}
double x0 = dataset.getXValue(series, item - 1);
double y0 = dataset.getYValue(series, item - 1);
if (Double.isNaN(y0) || Double.isNaN(x0)) {
return;
}
RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
double transX0 = domainAxis.valueToJava2D(x0, dataArea, xAxisLocation);
double transY0 = rangeAxis.valueToJava2D(y0, dataArea, yAxisLocation);
double transX1 = domainAxis.valueToJava2D(x1, dataArea, xAxisLocation);
double transY1 = rangeAxis.valueToJava2D(y1, dataArea, yAxisLocation);
// only draw if we have good values
if (Double.isNaN(transX0) || Double.isNaN(transY0)
|| Double.isNaN(transX1) || Double.isNaN(transY1)) {
return;
}
Point2D.Double point0 = new Point2D.Double();
Point2D.Double point1 = new Point2D.Double();
Point2D.Double point2 = new Point2D.Double();
Point2D.Double point3 = new Point2D.Double();
if (item == 1) {
point0 = null;
}
else {
point0.x = domainAxis.valueToJava2D(dataset.getXValue(series,
item - 2), dataArea, xAxisLocation);
point0.y = rangeAxis.valueToJava2D(dataset.getYValue(series,
item - 2), dataArea, yAxisLocation);
}
point1.x = transX0;
point1.y = transY0;
point2.x = transX1;
point2.y = transY1;
if ((item + 1) == dataset.getItemCount(series)) {
point3 = null;
}
else {
point3.x = domainAxis.valueToJava2D(dataset.getXValue(series,
item + 1), dataArea, xAxisLocation);
point3.y = rangeAxis.valueToJava2D(dataset.getYValue(series,
item + 1), dataArea, yAxisLocation);
}
int steps = ((int) ((point2.x - point1.x) / 0.2) < 30)
? (int) ((point2.x - point1.x) / 0.2) : 30;
Point2D.Double[] points = getBezierCurve(point0, point1, point2,
point3, 1, steps);
for (int i = 1; i < points.length; i++) {
transX0 = points[i - 1].x;
transY0 = points[i - 1].y;
transX1 = points[i].x;
transY1 = points[i].y;
PlotOrientation orientation = plot.getOrientation();
if (orientation == PlotOrientation.HORIZONTAL) {
state.workingLine.setLine(transY0, transX0, transY1, transX1);
}
else if (orientation == PlotOrientation.VERTICAL) {
state.workingLine.setLine(transX0, transY0, transX1, transY1);
}
if (state.workingLine.intersects(dataArea)) {
drawFirstPassShape(g2, pass, series, item, state.workingLine);
}
}
}
/**
* Draws the item shapes and adds chart entities (second pass). This method
* draws the shapes which mark the item positions. If <code>entities</code>
* is not <code>null</code> it will be populated with entity information
* for points that fall within the data area.
*
* @param g2 the graphics device.
* @param plot the plot (can be used to obtain standard color
* information etc).
* @param domainAxis the domain axis.
* @param dataArea the area within which the data is being drawn.
* @param rangeAxis the range axis.
* @param dataset the dataset.
* @param pass the pass.
* @param series the series index (zero-based).
* @param item the item index (zero-based).
* @param crosshairState the crosshair state.
* @param entities the entity collection.
*/
protected void drawSecondaryPass(Graphics2D g2, XYPlot plot,
XYDataset dataset, int pass, int series, int item,
ValueAxis domainAxis, Rectangle2D dataArea,
ValueAxis rangeAxis, CrosshairState crosshairState,
EntityCollection entities) {
// super.drawSecondaryPass(g2, plot, dataset, pass, series, item,
// domainAxis, dataArea, rangeAxis, crosshairState, entities);
}
/**
* Updates the control points.
*
* @param point0
* @param point1
* @param point2
* @param point3
* @param control1
* @param control2
* @param smooth
*/
public static void getControlPoints(Point2D.Double point0,
Point2D.Double point1, Point2D.Double point2,
Point2D.Double point3, Point2D.Double control1,
Point2D.Double control2, double smooth) {
// Reference: http://www.antigrain.com/research/bezier_interpolation/
if (point0 == null) point0 = point1; //new Point2D.Double(0, 0);
if (point3 == null) point3 = point2; //new Point2D.Double(0, 0);
Point2D.Double c1 = new Point2D.Double(
(point0.x + point1.x) / 2.0, (point0.y + point1.y) / 2.0);
Point2D.Double c2 = new Point2D.Double(
(point1.x + point2.x) / 2.0, (point1.y + point2.y) / 2.0);
Point2D.Double c3 = new Point2D.Double(
(point2.x + point3.x) / 2.0, (point2.y + point3.y) / 2.0);
double len1 = point1.distance(point0);
double len2 = point2.distance(point1);
double len3 = point3.distance(point2);
double k1 = len1 / (len1 + len2);
double k2 = len2 / (len2 + len3);
Point2D.Double m1 = new Point2D.Double(
c1.x + (c2.x - c1.x) * k1, c1.y + (c2.y - c1.y) * k1);
Point2D.Double m2 = new Point2D.Double(
c2.x + (c3.x - c2.x) * k2, c2.y + (c3.y - c2.y) * k2);
control1.setLocation(new Point2D.Double(
m1.x + (c2.x - m1.x) * smooth + point1.x - m1.x,
m1.y + (c2.y - m1.y) * smooth + point1.y - m1.y));
control2.setLocation(new Point2D.Double(
m2.x + (c2.x - m2.x) * smooth + point2.x - m2.x,
m2.y + (c2.y - m2.y) * smooth + point2.y - m2.y));
}
/**
* Returns the points for a bezier curve.
*
* @param point0
* @param point1
* @param point2
* @param point3
* @param smooth
* @param steps
*
* @return The curve points.
*/
public static Point2D.Double[] getBezierCurve(Point2D.Double point0,
Point2D.Double point1, Point2D.Double point2,
Point2D.Double point3, double smooth, int steps) {
Point2D.Double control1 = new Point2D.Double();
Point2D.Double control2 = new Point2D.Double();
getControlPoints(point0, point1, point2, point3, control1, control2,
smooth);
Point2D.Double C = new Point2D.Double(
3 * (control1.x - point1.x), 3 * (control1.y - point1.y));
Point2D.Double B = new Point2D.Double(3 * (control2.x - control1.x)
- C.x, 3 * (control2.y - control1.y) - C.y);
Point2D.Double A = new Point2D.Double(point2.x - point1.x - C.x - B.x,
point2.y - point1.y - C.y - B.y);
Point2D.Double[] res = new Point2D.Double[steps + 1];
double stepSize = 1.0 / steps;
double step = stepSize;
res[0] = point1;
for (int i = 1; i < steps; i++) {
res[i] = new Point2D.Double(A.x * Math.pow(step, 3) + B.x
* Math.pow(step, 2) + C.x * step + point1.x, A.y
* Math.pow(step, 3) + B.y * Math.pow(step, 2) + C.y * step
+ point1.y);
//System.out.println(step + " : " + res[i]);
step += stepSize;
}
res[steps] = point2;
return res;
}
}