bundles/core/org.eclipse.apogy.core.environment.orbit.earth.ui/src/org/eclipse/apogy/core/environment/orbit/earth/ui/composites/VisibilityPassSpacecraftPositionHistoryAzElComposite.java

/*******************************************************************************
 * Copyright (c) 2018 Agence spatiale canadienne / Canadian Space Agency
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Pierre Allard,
 *     Regent L'Archeveque - initial API and implementation
 * 
 * SPDX-License-Identifier: EPL-1.0
 * 
 *******************************************************************************/
package org.eclipse.apogy.core.environment.orbit.earth.ui.composites;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Polygon;
import java.awt.geom.GeneralPath;
import java.awt.geom.Rectangle2D;

import org.eclipse.apogy.core.environment.orbit.earth.VisibilityPassSpacecraftPosition;
import org.eclipse.apogy.core.environment.orbit.earth.VisibilityPassSpacecraftPositionHistory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotRenderingInfo;
import org.jfree.chart.plot.PolarPlot;
import org.jfree.chart.renderer.DefaultPolarItemRenderer;
import org.jfree.data.Range;
import org.jfree.data.xy.XYDataset;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.experimental.chart.swt.ChartComposite;

public class VisibilityPassSpacecraftPositionHistoryAzElComposite extends Composite {
	private VisibilityPassSpacecraftPositionHistory positionHistory = null;

	private JFreeChart chart;
	private XYSeriesCollection xySeriesCollection = null;
	private XYSeries currentDataSeries = null;

	public VisibilityPassSpacecraftPositionHistoryAzElComposite(Composite parent, int style) {
		super(parent, style);
		setLayout(new FillLayout());

		// Adds the chart parentComposite.
		new ChartComposite(this, SWT.NONE, getChart(), true);
	}

	public VisibilityPassSpacecraftPositionHistory getPositionHistory() {
		return this.positionHistory;
	}

	public void setPositionHistory(VisibilityPassSpacecraftPositionHistory positionHistory) {
		// Clears current series.
		getCurrentDataSeries().clear();

		this.positionHistory = positionHistory;

		// Populates the series with the new data if applicable.
		if (positionHistory != null) {
			populateDataSeries(getCurrentDataSeries(), positionHistory);
		}
	}

	protected JFreeChart getChart() {
		if (this.chart == null) {
			this.chart = ChartFactory.createPolarChart("Elevation vs Azimuth", getXYSeriesCollection(), false, false,
					false);

			final PolarPlot plot = (PolarPlot) this.chart.getPlot();
			plot.setBackgroundPaint(Color.white);
			plot.setAngleGridlinePaint(Color.black);
			plot.setAngleLabelPaint(Color.black);
			plot.setRadiusGridlinePaint(Color.black);
			plot.setRadiusGridlinesVisible(true);
			plot.setNoDataMessage("No Data.");

			plot.getAxis().setAutoRange(false);
			plot.getAxis().setInverted(true);
			plot.getAxis().setRange(new Range(0, 90.0));
			plot.getAxis().setAxisLineStroke(new BasicStroke(2.0f));
			plot.getAxis().setAxisLinePaint(Color.black);

			DefaultPolarItemRenderer defaultPolarItemRenderer = new DefaultPolarItemRenderer() {
				/**
				 * 
				 */
				private static final long serialVersionUID = 3822995919130258873L;

				@Override
				public void drawSeries(Graphics2D g2, Rectangle2D dataArea, PlotRenderingInfo info, PolarPlot plot,
						XYDataset dataset, int seriesIndex) {
					g2.setPaint(lookupSeriesPaint(seriesIndex));
					g2.setStroke(lookupSeriesStroke(seriesIndex));

					GeneralPath polyline = new GeneralPath();
					int numPoints = dataset.getItemCount(seriesIndex);

					Point point = null;
					Point previousPoint = null;
					for (int i = 0; i < numPoints - 1; i++) {
						double theta = dataset.getXValue(seriesIndex, i);
						double radius = dataset.getYValue(seriesIndex, i);
						point = plot.translateValueThetaRadiusToJava2D(theta, radius, dataArea);

						if (i == 0) {
							polyline.moveTo(point.x, point.y);
						} else {
							polyline.lineTo(point.x, point.y);
						}

						if (i + 1 < numPoints - 1) {
							previousPoint = point;
						}
					}

					// Draws the data line.
					g2.draw(polyline);

					// Adds an arrow at the last point.
					if (point != null) {
						double deltaX = point.x - previousPoint.x;
						double deltaY = point.y - previousPoint.y;
						double theta = getRotationAngle(deltaX, deltaY);

						g2.translate(point.x, point.y);
						g2.rotate(theta);

						int x1Points[] = { 0, -20, -20 };
						int y1Points[] = { 0, 5, -5 };
						Polygon polygon = new Polygon(x1Points, y1Points, x1Points.length);

						g2.draw(polygon);
						g2.fillPolygon(polygon);

						// Un-do the transform.
						g2.rotate(-theta);
						g2.translate(-point.x, -point.y);
					}
				}
			};
			plot.setRenderer(defaultPolarItemRenderer);

		}
		return this.chart;
	}

	private double getRotationAngle(double deltaX, double deltaY) {
		double theta = 0;

		if (deltaX > 0) {
			if (deltaY > 0) {
				theta = Math.atan(Math.abs(deltaY) / Math.abs(deltaX));
			} else {
				theta = -1.0 * Math.atan(Math.abs(deltaY) / Math.abs(deltaX));
			}
		} else {
			if (deltaY > 0) {
				theta = Math.PI - Math.atan(Math.abs(deltaY) / Math.abs(deltaX));
			} else {
				theta = Math.atan(Math.abs(deltaY) / Math.abs(deltaX)) - Math.PI;
			}
		}

		return theta;
	}

	protected XYSeriesCollection getXYSeriesCollection() {
		if (this.xySeriesCollection == null) {
			this.xySeriesCollection = new XYSeriesCollection();
			this.xySeriesCollection.addSeries(getCurrentDataSeries());
		}

		return this.xySeriesCollection;
	}

	protected XYSeries getCurrentDataSeries() {
		if (this.currentDataSeries == null) {
			this.currentDataSeries = new XYSeries("Pass", false);
			if (getPositionHistory() != null) {
				populateDataSeries(this.currentDataSeries, getPositionHistory());
			}
		}

		return this.currentDataSeries;
	}

	protected void populateDataSeries(XYSeries xySeries, VisibilityPassSpacecraftPositionHistory positionHistory) {
		for (VisibilityPassSpacecraftPosition position : positionHistory.getPositions()) {
			double azimuth = Math.toDegrees(position.getAzimuth());
			double elevation = 90.0 - Math.toDegrees(position.getElevation());
			xySeries.add(azimuth, elevation);
		}
	}
}