gov/nasa/worldwind/geom/Quadrilateral.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.geom;
   8
   9 import com.sun.opengl.util.*;
  10 import gov.nasa.worldwind.*;
  11
  12 import javax.media.opengl.*;
  13 import java.awt.*;
  14 import java.nio.*;
  15
  16 /**
  17  * @author tag
  18  * @version $Id: Quadrilateral.java 2233 2007-07-06 23:56:34Z tgaskins $
  19  */
  20 public class Quadrilateral implements Renderable, Movable
  21 {
  22     private LatLon southwestCorner;
  23     private LatLon northeastCorner;
  24     private double elevation;
  25     private Vec4 referenceCenter;
  26     private DoubleBuffer vertices;
  27     private int antiAliasHint = GL.GL_FASTEST;
  28     private Color color = Color.WHITE;
  29
  30     public Quadrilateral(LatLon southwestCorner, LatLon northeastCorner, double elevation)
  31     {
  32         if (southwestCorner == null || northeastCorner == null)
  33         {
  34             String msg = WorldWind.retrieveErrMsg("nullValue.PositionIsNull");
  35             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  36             throw new IllegalArgumentException(msg);
  37         }
  38
  39         this.southwestCorner = southwestCorner;
  40         this.northeastCorner = northeastCorner;
  41         this.elevation = elevation;
  42     }
  43
  44     public Quadrilateral(Sector sector, double elevation)
  45     {
  46         if (sector == null)
  47         {
  48             String msg = WorldWind.retrieveErrMsg("nullValue.SectorIsNull");
  49             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  50             throw new IllegalArgumentException(msg);
  51         }
  52
  53         this.southwestCorner = new LatLon(sector.getMinLatitude(), sector.getMinLongitude());
  54         this.northeastCorner = new LatLon(sector.getMaxLatitude(), sector.getMaxLongitude());
  55         this.elevation = elevation;
  56     }
  57
  58     public Color getColor()
  59     {
  60         return color;
  61     }
  62
  63     public void setColor(Color color)
  64     {
  65         if (color == null)
  66         {
  67             String msg = WorldWind.retrieveErrMsg("nullValue.ColorIsNull");
  68             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  69             throw new IllegalArgumentException(msg);
  70         }
  71
  72         this.color = color;
  73     }
  74
  75     public int getAntiAliasHint()
  76     {
  77         return antiAliasHint;
  78     }
  79
  80     public void setAntiAliasHint(int hint)
  81     {
  82         if (!(hint == GL.GL_DONT_CARE || hint == GL.GL_FASTEST || hint == GL.GL_NICEST))
  83         {
  84             String msg = WorldWind.retrieveErrMsg("generic.InvalidHint");
  85             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
  86             throw new IllegalArgumentException(msg);
  87         }
  88
  89         this.antiAliasHint = hint;
  90     }
  91
  92     public void setCorners(LatLon southWest, LatLon northEast)
  93     {
  94         this.southwestCorner = southWest;
  95         this.northeastCorner = northEast;
  96         this.vertices = null;
  97     }
  98
  99     public LatLon[] getCorners()
 100     {
 101         LatLon[] retVal = new LatLon[2];
 102
 103         retVal[0] = this.southwestCorner;
 104         retVal[1] = this.northeastCorner;
 105
 106         return retVal;
 107     }
 108
 109     public double getElevation()
 110     {
 111         return elevation;
 112     }
 113
 114     public void setElevation(double elevation)
 115     {
 116         this.elevation = elevation;
 117         this.vertices = null;
 118     }
 119
 120     private void intializeGeometry(DrawContext dc)
 121     {
 122         DoubleBuffer verts = BufferUtil.newDoubleBuffer(12);
 123
 124         Vec4[] p = new Vec4[4];
 125
 126         p[0] = dc.getGlobe().computePointFromPosition(this.southwestCorner.getLatitude(),
 127             this.southwestCorner.getLongitude(), this.elevation);
 128         p[1] = dc.getGlobe().computePointFromPosition(this.southwestCorner.getLatitude(),
 129             this.northeastCorner.getLongitude(), this.elevation);
 130         p[2] = dc.getGlobe().computePointFromPosition(this.northeastCorner.getLatitude(),
 131             this.northeastCorner.getLongitude(), this.elevation);
 132         p[3] = dc.getGlobe().computePointFromPosition(this.northeastCorner.getLatitude(),
 133             this.southwestCorner.getLongitude(), this.elevation);
 134
 135         Vec4 refcenter = new Vec4(
 136             (p[0].x + p[2].x) / 2.0,
 137             (p[0].y + p[2].y) / 2.0,
 138             (p[0].z + p[2].z) / 2.0);
 139
 140         for (int i = 0; i < 4; i++)
 141         {
 142             verts.put(p[i].x - refcenter.x);
 143             verts.put(p[i].y - refcenter.y);
 144             verts.put(p[i].z - refcenter.z);
 145         }
 146
 147         this.referenceCenter = refcenter;
 148         this.vertices = verts;
 149     }
 150
 151     public void render(DrawContext dc)
 152     {
 153         if (dc == null)
 154         {
 155             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 156             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 157             throw new IllegalStateException(message);
 158         }
 159
 160         if (this.vertices == null)
 161         {
 162             this.intializeGeometry(dc);
 163
 164             if (this.vertices == null)
 165                 return; // TODO: log a warning
 166         }
 167
 168         GL gl = dc.getGL();
 169
 170         int attrBits = GL.GL_HINT_BIT | GL.GL_CURRENT_BIT;
 171         if (!dc.isPickingMode())
 172         {
 173             if (this.color.getAlpha() != 255)
 174                 attrBits |= GL.GL_COLOR_BUFFER_BIT;
 175         }
 176
 177         gl.glPushAttrib(attrBits);
 178         gl.glPushClientAttrib(GL.GL_CLIENT_VERTEX_ARRAY_BIT);
 179         dc.getView().pushReferenceCenter(dc, this.referenceCenter);
 180
 181         try
 182         {
 183             if (!dc.isPickingMode())
 184             {
 185                 if (this.color.getAlpha() != 255)
 186                 {
 187                     gl.glEnable(GL.GL_BLEND);
 188                     gl.glBlendFunc(GL.GL_SRC_ALPHA, GL.GL_ONE_MINUS_SRC_ALPHA);
 189                 }
 190                 dc.getGL().glColor4ub((byte) this.color.getRed(), (byte) this.color.getGreen(),
 191                     (byte) this.color.getBlue(), (byte) this.color.getAlpha());
 192             }
 193
 194             gl.glHint(GL.GL_POLYGON_SMOOTH_HINT, this.antiAliasHint);
 195             gl.glEnableClientState(GL.GL_VERTEX_ARRAY);
 196             gl.glVertexPointer(3, GL.GL_DOUBLE, 0, this.vertices.rewind());
 197             gl.glDrawArrays(GL.GL_QUADS, 0, 4);
 198         }
 199         finally
 200         {
 201             gl.glPopClientAttrib();
 202             gl.glPopAttrib();
 203             dc.getView().popReferenceCenter(dc);
 204         }
 205     }
 206
 207     public Position getReferencePosition()
 208     {
 209         return new Position(this.southwestCorner, this.elevation);
 210     }
 211
 212     public void move(Position delta)
 213     {
 214         if (delta == null)
 215         {
 216             String msg = WorldWind.retrieveErrMsg("nullValue.PositionIsNull");
 217             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
 218             throw new IllegalArgumentException(msg);
 219         }
 220
 221         this.northeastCorner = this.northeastCorner.add(delta);
 222         this.southwestCorner = this.southwestCorner.add(delta);
 223         this.elevation = this.elevation + delta.getElevation();
 224         this.vertices = null;
 225     }
 226
 227     public void moveTo(Position position)
 228     {
 229         if (position == null)
 230         {
 231             String msg = WorldWind.retrieveErrMsg("nullValue.PositionIsNull");
 232             WorldWind.logger().log(java.util.logging.Level.FINE, msg);
 233             throw new IllegalArgumentException(msg);
 234         }
 235
 236         Position delta = position.subtract(this.getReferencePosition());
 237         this.move(delta);
 238     }
 239 }