CartesianCoordinateSystem.java
/*
* Copyright 2003-2004, Franz-Josef Elmer, All rights reserved
*
* 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 program 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
* (http://www.gnu.org/copyleft/lesser.html).
*
* 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
*/
package jcckit.plot;
import jcckit.data.DataPoint;
import jcckit.graphic.ClippingRectangle;
import jcckit.graphic.ClippingShape;
import jcckit.graphic.GraphPoint;
import jcckit.graphic.GraphicAttributes;
import jcckit.graphic.GraphicalComposite;
import jcckit.graphic.GraphicalElement;
import jcckit.graphic.LineAttributes;
import jcckit.graphic.Polygon;
import jcckit.graphic.Text;
import jcckit.transformation.CartesianTransformation;
import jcckit.transformation.Transformation;
import jcckit.util.ConfigParameters;
/**
* A Cartesian coordinate system. One or both axes can be logarithmic.
*
* @author Franz-Josef Elmer
*/
public class CartesianCoordinateSystem implements CoordinateSystem {
/** Configuration parameter key. */
public static final String ORIGIN_KEY = "origin",
X_AXIS_KEY = "xAxis",
Y_AXIS_KEY = "yAxis";
private final CartesianTransformation _transformation;
private final GraphicalComposite _view;
private final ClippingRectangle _clippingRectangle;
/**
* Creates an instance from the specified configuration parameters.
* <table border=1 cellpadding=5>
* <tr><th>Key & Default Value</th><th>Type</th><th>Mandatory</th>
* <th>Description</th></tr>
* <tr><td><tt>origin = 0.15, 0.1</tt></td>
* <td><tt>double[]</tt></td><td>no</td>
* <td>Position (in device-independent coordinates) of the lower-left
* corner of the axis box.</td></tr>
* <tr><td><tt>xAxis</tt></td>
* <td><tt>ConfigParameters</tt></td><td>no</td>
* <td>Parameters defining the x-axis. For definitions and default
* values see {@link AxisParameters#createXAxis
* AxisParameters.createXAxis()}.</td></tr>
* <tr><td><tt>yAxis</tt></td>
* <td><tt>ConfigParameters</tt></td><td>no</td>
* <td>Parameters defining the y-axis. For definitions and default
* values see {@link AxisParameters#createYAxis
* AxisParameters.createYAxis()}.</td></tr>
* </table>
*/
public CartesianCoordinateSystem(ConfigParameters config) {
this(new GraphPoint(config.getDoubleArray(ORIGIN_KEY,
new double[] {0.15, 0.1})),
AxisParameters.createXAxis(config.getNode(X_AXIS_KEY)),
AxisParameters.createYAxis(config.getNode(Y_AXIS_KEY)));
}
/**
* Creates an instance for the specified origin and parameters
* of both axes.
* @param origin Position (in device-independent coordinates) of the
* lower-left corner of the axis box.
* @param xAxisParameters Parameters of the x-axis.
* @param yAxisParameters Parameters of the y-axis.
*/
public CartesianCoordinateSystem(GraphPoint origin,
AxisParameters xAxisParameters,
AxisParameters yAxisParameters) {
double x = origin.getX();
double y = origin.getY();
_transformation = new CartesianTransformation(xAxisParameters.logScale,
yAxisParameters.logScale,
new DataPoint(xAxisParameters.minimum, yAxisParameters.minimum),
new GraphPoint(x, y),
new DataPoint(xAxisParameters.maximum, yAxisParameters.maximum),
new GraphPoint(x + xAxisParameters.axisLength,
y + yAxisParameters.axisLength));
_clippingRectangle = new ClippingRectangle(x, y,
x + xAxisParameters.axisLength,
y + yAxisParameters.axisLength);
_view = new GraphicalComposite(null);
createView(origin, xAxisParameters, yAxisParameters);
}
/** Creates the graphical representation of this coordinate system. */
private void createView(GraphPoint origin,
AxisParameters xAxisParameters,
AxisParameters yAxisParameters) {
double x0 = origin.getX();
double x1 = x0 + xAxisParameters.axisLength;
double y0 = origin.getY();
double y1 = y0 + yAxisParameters.axisLength;
GraphPoint lowerLeftCorner = new GraphPoint(x0, y0);
GraphPoint upperLeftCorner = new GraphPoint(x0, y1);
GraphPoint lowerRightCorner = new GraphPoint(x1, y0);
GraphPoint upperRightCorner = new GraphPoint(x1, y1);
LineAttributes xLineAttributes = xAxisParameters.axisAttributes;
LineAttributes yLineAttributes = yAxisParameters.axisAttributes;
createTicsAndGrid(true, y0, y1, xAxisParameters);
createTicsAndGrid(false, x0, x1, yAxisParameters);
addLine(lowerLeftCorner, lowerRightCorner, xLineAttributes);
addLine(lowerLeftCorner, upperLeftCorner, yLineAttributes);
addLine(upperLeftCorner, upperRightCorner, xLineAttributes);
addLine(lowerRightCorner, upperRightCorner, yLineAttributes);
createLabel(0.5 * (x0 + x1), y0, xAxisParameters);
createLabel(x0, 0.5 * (y0 + y1), yAxisParameters);
}
private void createLabel(double x, double y, AxisParameters parameters) {
if (parameters.axisLabel.length() > 0) {
_view.addElement(new Text(
new GraphPoint(x + parameters.axisLabelPosition.getX(),
y + parameters.axisLabelPosition.getY()),
parameters.axisLabel, parameters.axisLabelAttributes));
}
}
private void createTicsAndGrid(boolean isXAxis, double low, double high,
AxisParameters parameters) {
double[] tics = parameters.calculateTics();
int offIndex = isXAxis ? 1 : 0;
double[] point = new double[2]; // helper array
for (int i = 0; i < tics.length; i++) {
point[1 - offIndex] = tics[i];
point[offIndex] = 1;
GraphPoint gPoint1 =
_transformation.transformToGraph(new DataPoint(point[0], point[1]));
point[0] = gPoint1.getX();
point[1] = gPoint1.getY();
point[offIndex] = high;
gPoint1 = new GraphPoint(point[0], point[1]);
point[offIndex] += parameters.ticLength;
addLine(gPoint1, new GraphPoint(point[0], point[1]),
parameters.ticAttributes);
point[offIndex] = low;
GraphPoint gPoint2 = new GraphPoint(point[0], point[1]);
if (parameters.grid) {
addLine(gPoint1, gPoint2, parameters.gridAttributes);
}
point[offIndex] -= parameters.ticLength;
addLine(gPoint2, new GraphPoint(point[0], point[1]),
parameters.ticAttributes);
if (parameters.ticLabelFormat != null) {
point[offIndex] += parameters.ticLength;
point[0] += parameters.ticLabelPosition.getX();
point[1] += parameters.ticLabelPosition.getY();
_view.addElement(new Text(new GraphPoint(point[0], point[1]),
parameters.ticLabelFormat.form(tics[i]),
parameters.ticLabelAttributes));
}
}
}
private void addLine(GraphPoint point1, GraphPoint point2,
GraphicAttributes attributes) {
Polygon line = new Polygon(attributes, false);
line.addPoint(point1);
line.addPoint(point2);
_view.addElement(line);
}
/**
* Returns the graphical representation of the coordinate system.
* In each call the same instance is returned.
*/
public GraphicalElement getView() {
return _view;
}
/**
* Returns the clipping rectangle of specified by the axis.
* In each call the same instance is returned.
*/
public ClippingShape getClippingShape() {
return _clippingRectangle;
}
/**
* Returns the transformation of data coordinates into the device-independent
* coordinates of the axis box.
* In each call the same instance is returned.
*/
public Transformation getTransformation() {
return _transformation;
}
}