X-Git-Url: http://gitweb.fperrin.net/?p=GpsPrune.git;a=blobdiff_plain;f=src%2Ftim%2Fprune%2Fdata%2FTrackExtents.java;fp=src%2Ftim%2Fprune%2Fdata%2FTrackExtents.java;h=0bf308172ceee02763bfe79f1a8f837db130bdd5;hp=0000000000000000000000000000000000000000;hb=ce6f2161b8596f7018d6a76bff79bc9e571f35fd;hpb=2d8cb72e84d5cc1089ce77baf1e34ea3ea2f8465

diff --git a/src/tim/prune/data/TrackExtents.java b/src/tim/prune/data/TrackExtents.java
new file mode 100644
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+++ b/src/tim/prune/data/TrackExtents.java
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+package tim.prune.data;
+
+/**
+ * Class to hold the extents of a track, in 2d and in 3d,
+ * and to calculate a square area with a default border
+ */
+public class TrackExtents
+{
+	/** Track object */
+	private Track _track = null;
+	/** X and Y ranges */
+	private DoubleRange _xRange   = null, _yRange   = null;
+
+	/** Border multiplier */
+	private static final double BORDER_MULTIPLIER = 1.1; // 10% border
+
+	/**
+	 * Constructor
+	 * @param inTrack track object to take extents from
+	 */
+	public TrackExtents(Track inTrack)
+	{
+		_track  = inTrack;
+		_xRange = inTrack.getXRange().copy();
+		_yRange = inTrack.getYRange().copy();
+	}
+
+
+	/**
+	 * Make the x and y ranges square with a default border around
+	 */
+	public void applySquareBorder()
+	{
+		// Find the middle of the x and y
+		final double midXvalue = _xRange.getMidValue();
+		final double midYvalue = _yRange.getMidValue();
+		// Find x and y range, take maximum
+		double xyRange = Math.max(_xRange.getRange(), _yRange.getRange()) * BORDER_MULTIPLIER;
+		if (getHorizontalDistanceMetres() < 10.0)
+		{
+			// all the points are near enough on the same spot, expand scale to avoid dividing by zero
+			xyRange = 0.1;
+		}
+
+		// Apply these new min and max to the ranges
+		_xRange.addValue(midXvalue - xyRange / 2.0);
+		_xRange.addValue(midXvalue + xyRange / 2.0);
+		_yRange.addValue(midYvalue - xyRange / 2.0);
+		_yRange.addValue(midYvalue + xyRange / 2.0);
+	}
+
+	/** @return x range */
+	public DoubleRange getXRange() {
+		return _xRange;
+	}
+
+	/** @return y range */
+	public DoubleRange getYRange() {
+		return _yRange;
+	}
+
+	/** @return altitude range */
+	public DoubleRange getAltitudeRange()
+	{
+		final int numPoints = _track.getNumPoints();
+		DoubleRange altRange = new DoubleRange();
+		for (int i=0; i<numPoints; i++)
+		{
+			DataPoint p = _track.getPoint(i);
+			if (p != null && p.hasAltitude()) {
+				altRange.addValue(p.getAltitude().getMetricValue());
+			}
+		}
+		return altRange;
+	}
+
+	/**
+	 * @return the greater of the N/S and E/W extent of the track, in metres (including border)
+	 */
+	public double getHorizontalDistanceMetres()
+	{
+		DoubleRange lonRange = _track.getLonRange();
+		DoubleRange latRange = _track.getLatRange();
+
+		// Find horizontal and vertical extents of enclosing rectangle
+		DataPoint southPoint = new DataPoint(new Latitude(latRange.getMinimum(), Coordinate.FORMAT_DEG),
+			new Longitude(lonRange.getMidValue(), Coordinate.FORMAT_DEG), null);
+		DataPoint northPoint = new DataPoint(new Latitude(latRange.getMaximum(), Coordinate.FORMAT_DEG),
+			new Longitude(lonRange.getMidValue(), Coordinate.FORMAT_DEG), null);
+		double nsDist = Distance.convertRadiansToDistance(
+			DataPoint.calculateRadiansBetween(northPoint, southPoint), UnitSetLibrary.UNITS_METRES); // both in m
+		// Same again for bottom and top, take maximum
+		DataPoint westPoint = new DataPoint(new Latitude(latRange.getMidValue(), Coordinate.FORMAT_DEG),
+			new Longitude(lonRange.getMinimum(), Coordinate.FORMAT_DEG), null);
+		DataPoint eastPoint = new DataPoint(new Latitude(latRange.getMidValue(), Coordinate.FORMAT_DEG),
+			new Longitude(lonRange.getMinimum(), Coordinate.FORMAT_DEG), null);
+		double ewDist = Distance.convertRadiansToDistance(
+			DataPoint.calculateRadiansBetween(westPoint, eastPoint), UnitSetLibrary.UNITS_METRES); // both in m
+		final double horizDistance = Math.max(nsDist, ewDist) * BORDER_MULTIPLIER;
+
+		return horizDistance;
+	}
+}