gov/nasa/worldwind/render/SurfaceEllipse.java

   1 /*
   2 Copyright (C) 2001, 2006 United States Government
   3 as represented by the Administrator of the
   4 National Aeronautics and Space Administration.
   5 All Rights Reserved.
   6 */
   7 package gov.nasa.worldwind.render;
   8
   9 import gov.nasa.worldwind.geom.*;
  10 import gov.nasa.worldwind.globes.Globe;
  11 import gov.nasa.worldwind.util.Logging;
  12
  13 import java.awt.*;
  14 import java.util.ArrayList;
  15
  16 /**
  17  * @author tag
  18  * @version $Id: SurfaceEllipse.java 2570 2007-08-16 22:31:33Z tgaskins $
  19  */
  20 public class SurfaceEllipse extends SurfacePolygon
  21 {
  22     private LatLon center;
  23     private double majorAxisLength;
  24     private double minorAxisLength;
  25     private Angle orientation;
  26     private int intervals;
  27
  28     public SurfaceEllipse(Globe globe, LatLon center, double majorAxisLength, double minorAxisLength, Angle orientation,
  29         int intervals)
  30     {
  31         super(makePositions(globe, center, majorAxisLength, minorAxisLength, orientation, intervals), null, null);
  32         this.globe = globe;
  33         this.center = center;
  34         this.majorAxisLength = majorAxisLength;
  35         this.minorAxisLength = minorAxisLength;
  36         this.orientation = orientation;
  37         this.intervals = intervals;
  38     }
  39
  40     public SurfaceEllipse(Globe globe, LatLon center, double majorAxisLength, double minorAxisLength, Angle orientation,
  41         int intervals, Color interiorColor, Color borderColor)
  42     {
  43         super(makePositions(globe, center, majorAxisLength, minorAxisLength, orientation, intervals), interiorColor,
  44             borderColor);
  45         this.globe = globe;
  46         this.center = center;
  47         this.majorAxisLength = majorAxisLength;
  48         this.minorAxisLength = minorAxisLength;
  49         this.orientation = orientation;
  50         this.intervals = intervals;
  51     }
  52
  53     public SurfaceEllipse(Globe globe, LatLon center, double majorAxisLength, double minorAxisLength, Angle orientation,
  54         int intervals, Color interiorColor, Color borderColor, Dimension textureSize)
  55     {
  56         super(makePositions(globe, center, majorAxisLength, minorAxisLength, orientation, intervals), interiorColor,
  57             borderColor, textureSize);
  58         this.globe = globe;
  59         this.center = center;
  60         this.majorAxisLength = majorAxisLength;
  61         this.minorAxisLength = minorAxisLength;
  62         this.orientation = orientation;
  63         this.intervals = intervals;
  64     }
  65
  66     public LatLon getCenter()
  67     {
  68         return this.center;
  69     }
  70
  71     public void setCenter(LatLon center)
  72     {
  73         this.center = center;
  74         this.setPositions(
  75             makePositions(this.globe, this.center, this.majorAxisLength, this.majorAxisLength, this.orientation,
  76                 this.intervals));
  77     }
  78
  79     public double getMajorAxisLength()
  80     {
  81         return majorAxisLength;
  82     }
  83
  84     public double getMinorAxisLength()
  85     {
  86         return minorAxisLength;
  87     }
  88
  89     public void setAxisLengths(double majorAxisLength, double minorAxisLength)
  90     {
  91         this.majorAxisLength = majorAxisLength;
  92         this.minorAxisLength = minorAxisLength;
  93         this.setPositions(
  94             makePositions(this.globe, this.center, this.majorAxisLength, this.majorAxisLength, this.orientation,
  95                 this.intervals));
  96     }
  97
  98     public Angle getOrientation()
  99     {
 100         return orientation;
 101     }
 102
 103     public void setOrientation(Angle orientation)
 104     {
 105         this.orientation = orientation;
 106         this.setPositions(
 107             makePositions(this.globe, this.center, this.majorAxisLength, this.majorAxisLength, this.orientation,
 108                 this.intervals));
 109     }
 110
 111     public int getIntervals()
 112     {
 113         return intervals;
 114     }
 115
 116     public void setIntervals(int intervals)
 117     {
 118         this.intervals = intervals;
 119         this.setPositions(
 120             makePositions(this.globe, this.center, this.majorAxisLength, this.majorAxisLength, this.orientation,
 121                 this.intervals));
 122     }
 123
 124     private static Iterable<LatLon> makePositions(Globe globe, LatLon center, double majorAxis, double minorAxis,
 125         Angle orientation, int intervals)
 126     {
 127         if (orientation == null)
 128             orientation = Angle.ZERO;
 129
 130         if (globe == null)
 131         {
 132             String message = Logging.getMessage("nullValue.GlobeIsNull");
 133             Logging.logger().severe(message);
 134             throw new IllegalArgumentException(message);
 135         }
 136
 137         if (center == null)
 138         {
 139             String message = Logging.getMessage("nullValue.CenterIsNull");
 140             Logging.logger().severe(message);
 141             throw new IllegalArgumentException(message);
 142         }
 143
 144         if (majorAxis <= 0)
 145         {
 146             String message = Logging.getMessage("Geom.MajorAxisInvalid", majorAxis);
 147             Logging.logger().severe(message);
 148             throw new IllegalArgumentException(message);
 149         }
 150
 151         if (minorAxis <= 0)
 152         {
 153             String message = Logging.getMessage("Geom.MajorAxisInvalid", minorAxis);
 154             Logging.logger().severe(message);
 155             throw new IllegalArgumentException(message);
 156         }
 157
 158         int numPositions = 1 + Math.max(intervals, 4);
 159         final ArrayList<LatLon> positions = new ArrayList<LatLon>();
 160
 161         double radius = globe.getRadiusAt(center.getLatitude(), center.getLongitude());
 162         double da = 2 * Math.PI / (numPositions - 1);
 163         for (int i = 0; i < numPositions; i++)
 164         {
 165             // azimuth runs positive clockwise from north and through 360¡.
 166             double angle = (i != numPositions - 1) ? i * da : 0;
 167             double azimuth = Math.PI / 2 - (angle + orientation.radians);
 168             double xLength = majorAxis * Math.cos(angle);
 169             double yLength = minorAxis * Math.sin(angle);
 170             double distance = Math.sqrt(xLength * xLength + yLength * yLength);
 171             LatLon p = LatLon.endPosition(center, azimuth, distance / radius);
 172             positions.add(p);
 173         }
 174
 175         return positions;
 176     }
 177 }