gov/nasa/worldwind/layers/AbstractLayer.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.layers;
   8
   9 import gov.nasa.worldwind.*;
  10
  11 /**
  12  * @author tag
  13  * @version $Id: AbstractLayer.java 1735 2007-05-05 09:50:26Z tgaskins $
  14  */
  15 public abstract class AbstractLayer extends WWObjectImpl implements Layer
  16 {
  17     private boolean enabled = true;
  18     private boolean pickable = true;
  19     private double opacity = 1d;
  20     private double minActiveAltitude = Double.MIN_VALUE;
  21     private double maxActiveAltitude = Double.MAX_VALUE;
  22
  23     public boolean isEnabled()
  24     {
  25         return this.enabled;
  26     }
  27
  28     public boolean isPickEnabled()
  29     {
  30         return pickable;
  31     }
  32
  33     public void setPickEnabled(boolean pickable)
  34     {
  35         this.pickable = pickable;
  36     }
  37
  38     public void setEnabled(boolean enabled)
  39     {
  40         this.enabled = enabled;
  41     }
  42
  43     public String getName()
  44     {
  45         return this.myName();
  46     }
  47
  48     public void setName(String name)
  49     {
  50         this.setValue(AVKey.DISPLAY_NAME, name);
  51     }
  52
  53     public String toString()
  54     {
  55         return this.myName();
  56     }
  57
  58     private String myName()
  59     {
  60         String myName = null;
  61         Object name = this.getValue(AVKey.DISPLAY_NAME);
  62         if (null != name)
  63             myName = name.toString();
  64         if (null == myName)
  65             myName = this.toString();
  66         return myName;
  67     }
  68
  69     public double getOpacity()
  70     {
  71         return opacity;
  72     }
  73
  74     public void setOpacity(double opacity)
  75     {
  76         this.opacity = opacity;
  77     }
  78
  79     public double getMinActiveAltitude()
  80     {
  81         return minActiveAltitude;
  82     }
  83
  84     public void setMinActiveAltitude(double minActiveAltitude)
  85     {
  86         this.minActiveAltitude = minActiveAltitude;
  87     }
  88
  89     public double getMaxActiveAltitude()
  90     {
  91         return maxActiveAltitude;
  92     }
  93
  94     public void setMaxActiveAltitude(double maxActiveAltitude)
  95     {
  96         this.maxActiveAltitude = maxActiveAltitude;
  97     }
  98
  99     /**
 100      * Indicates whether the layer is in the view. The method implemented here is a default indicating the layer is in
 101      * view. Subclasses able to determine their presence in the view should override this implementation.
 102      *
 103      * @param dc the current draw context
 104      * @return <code>true</code> if the layer is in the view, <code>false</code> otherwise.
 105      */
 106     public boolean isLayerInView(DrawContext dc)
 107     {
 108         if (dc == null)
 109         {
 110             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 111             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 112             throw new IllegalStateException(message);
 113         }
 114
 115         return true;
 116     }
 117
 118     /**
 119      * Indicates whether the layer is active based on arbitrary criteria. The method implemented here is a default
 120      * indicating the layer is active if the current altitude is within the layer's min and max active altitudes.
 121      * Subclasses able to consider more criteria should override this implementation.
 122      * @param dc the current draw context
 123      * @return <code>true</code> if the layer is active, <code>false</code> otherwise.
 124      */
 125     public boolean isLayerActive(DrawContext dc)
 126     {
 127         if (dc == null)
 128         {
 129             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 130             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 131             throw new IllegalStateException(message);
 132         }
 133
 134         if (null == dc.getView())
 135         {
 136             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 137             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 138             throw new IllegalStateException(message);
 139         }
 140
 141         double altitude = dc.getView().getAltitude();
 142
 143         return altitude >= this.minActiveAltitude && altitude <= this.maxActiveAltitude;
 144     }
 145
 146     /**
 147      * @param dc the current draw context
 148      * @throws IllegalArgumentException if <code>dc</code> is null, or <code>dc</code>'s <code>Globe</code> or
 149      *                                  <code>View</code> is null
 150      */
 151     public void render(DrawContext dc)
 152     {
 153         if (!this.enabled)
 154             return; // Don't check for arg errors if we're disabled
 155
 156         if (null == dc)
 157         {
 158             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 159             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 160             throw new IllegalStateException(message);
 161         }
 162
 163         if (null == dc.getGlobe())
 164         {
 165             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoGlobeSpecifiedInDrawingContext");
 166             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 167             throw new IllegalStateException(message);
 168         }
 169
 170         if (null == dc.getView())
 171         {
 172             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 173             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 174             throw new IllegalStateException(message);
 175         }
 176
 177         if (!this.isLayerActive(dc))
 178             return;
 179
 180         if (!this.isLayerInView(dc))
 181             return;
 182
 183         this.doRender(dc);
 184     }
 185
 186     public void pick(DrawContext dc, java.awt.Point point)
 187     {
 188         if (!this.enabled)
 189             return; // Don't check for arg errors if we're disabled
 190
 191         if (null == dc)
 192         {
 193             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 194             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 195             throw new IllegalStateException(message);
 196         }
 197
 198         if (null == dc.getGlobe())
 199         {
 200             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoGlobeSpecifiedInDrawingContext");
 201             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 202             throw new IllegalStateException(message);
 203         }
 204
 205         if (null == dc.getView())
 206         {
 207             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 208             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 209             throw new IllegalStateException(message);
 210         }
 211
 212         if (!this.isLayerActive(dc))
 213             return;
 214
 215         if (!this.isLayerInView(dc))
 216             return;
 217
 218         this.doPick(dc, point);
 219     }
 220
 221     protected void doPick(DrawContext dc, java.awt.Point point)
 222     {
 223         // any state that could change the color needs to be disabled, such as GL_TEXTURE, GL_LIGHTING or GL_FOG.
 224         // re-draw with unique colors
 225         // store the object info in the selectable objects table
 226         // read the color under the coursor
 227         // use the color code as a key to retrieve a selected object from the selectable objects table
 228         // create an instance of the PickedObject and add to the dc via the dc.addPickedObject() method
 229     }
 230
 231     public void dispose() // override if disposal is a supported operation
 232     {
 233     }
 234
 235     protected abstract void doRender(DrawContext dc);
 236 }