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 2080 2007-06-18 16:41:30Z 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.MAX_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         Object n = this.getValue(AVKey.DISPLAY_NAME);
  46
  47         return n != null ? n.toString() : this.toString();
  48     }
  49
  50     public void setName(String name)
  51     {
  52         this.setValue(AVKey.DISPLAY_NAME, name);
  53     }
  54
  55     public String toString()
  56     {
  57         Object n = this.getValue(AVKey.DISPLAY_NAME);
  58
  59         return n != null ? n.toString() : super.toString();
  60     }
  61
  62     public double getOpacity()
  63     {
  64         return opacity;
  65     }
  66
  67     public void setOpacity(double opacity)
  68     {
  69         this.opacity = opacity;
  70     }
  71
  72     public double getMinActiveAltitude()
  73     {
  74         return minActiveAltitude;
  75     }
  76
  77     public void setMinActiveAltitude(double minActiveAltitude)
  78     {
  79         this.minActiveAltitude = minActiveAltitude;
  80     }
  81
  82     public double getMaxActiveAltitude()
  83     {
  84         return maxActiveAltitude;
  85     }
  86
  87     public void setMaxActiveAltitude(double maxActiveAltitude)
  88     {
  89         this.maxActiveAltitude = maxActiveAltitude;
  90     }
  91
  92     /**
  93      * Indicates whether the layer is in the view. The method implemented here is a default indicating the layer is in
  94      * view. Subclasses able to determine their presence in the view should override this implementation.
  95      *
  96      * @param dc the current draw context
  97      * @return <code>true</code> if the layer is in the view, <code>false</code> otherwise.
  98      */
  99     public boolean isLayerInView(DrawContext dc)
 100     {
 101         if (dc == null)
 102         {
 103             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 104             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 105             throw new IllegalStateException(message);
 106         }
 107
 108         return true;
 109     }
 110
 111     /**
 112      * Indicates whether the layer is active based on arbitrary criteria. The method implemented here is a default
 113      * indicating the layer is active if the current altitude is within the layer's min and max active altitudes.
 114      * Subclasses able to consider more criteria should override this implementation.
 115      *
 116      * @param dc the current draw context
 117      * @return <code>true</code> if the layer is active, <code>false</code> otherwise.
 118      */
 119     public boolean isLayerActive(DrawContext dc)
 120     {
 121         if (dc == null)
 122         {
 123             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 124             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 125             throw new IllegalStateException(message);
 126         }
 127
 128         if (null == dc.getView())
 129         {
 130             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 131             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 132             throw new IllegalStateException(message);
 133         }
 134
 135         double altitude = dc.getView().getAltitude();
 136
 137         return altitude >= this.minActiveAltitude && altitude <= this.maxActiveAltitude;
 138     }
 139
 140     /**
 141      * @param dc the current draw context
 142      * @throws IllegalArgumentException if <code>dc</code> is null, or <code>dc</code>'s <code>Globe</code> or
 143      *                                  <code>View</code> is null
 144      */
 145     public void render(DrawContext dc)
 146     {
 147         if (!this.enabled)
 148             return; // Don't check for arg errors if we're disabled
 149
 150         if (null == dc)
 151         {
 152             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 153             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 154             throw new IllegalStateException(message);
 155         }
 156
 157         if (null == dc.getGlobe())
 158         {
 159             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoGlobeSpecifiedInDrawingContext");
 160             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 161             throw new IllegalStateException(message);
 162         }
 163
 164         if (null == dc.getView())
 165         {
 166             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 167             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 168             throw new IllegalStateException(message);
 169         }
 170
 171         if (!this.isLayerActive(dc))
 172             return;
 173
 174         if (!this.isLayerInView(dc))
 175             return;
 176
 177         this.doRender(dc);
 178     }
 179
 180     public void pick(DrawContext dc, java.awt.Point point)
 181     {
 182         if (!this.enabled)
 183             return; // Don't check for arg errors if we're disabled
 184
 185         if (null == dc)
 186         {
 187             String message = WorldWind.retrieveErrMsg("nullValue.DrawContextIsNull");
 188             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 189             throw new IllegalStateException(message);
 190         }
 191
 192         if (null == dc.getGlobe())
 193         {
 194             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoGlobeSpecifiedInDrawingContext");
 195             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 196             throw new IllegalStateException(message);
 197         }
 198
 199         if (null == dc.getView())
 200         {
 201             String message = WorldWind.retrieveErrMsg("layers.AbstractLayer.NoViewSpecifiedInDrawingContext");
 202             WorldWind.logger().log(java.util.logging.Level.FINE, message);
 203             throw new IllegalStateException(message);
 204         }
 205
 206         if (!this.isLayerActive(dc))
 207             return;
 208
 209         if (!this.isLayerInView(dc))
 210             return;
 211
 212         this.doPick(dc, point);
 213     }
 214
 215     protected void doPick(DrawContext dc, java.awt.Point point)
 216     {
 217         // any state that could change the color needs to be disabled, such as GL_TEXTURE, GL_LIGHTING or GL_FOG.
 218         // re-draw with unique colors
 219         // store the object info in the selectable objects table
 220         // read the color under the coursor
 221         // use the color code as a key to retrieve a selected object from the selectable objects table
 222         // create an instance of the PickedObject and add to the dc via the dc.addPickedObject() method
 223     }
 224
 225     public void dispose() // override if disposal is a supported operation
 226     {
 227     }
 228
 229     protected abstract void doRender(DrawContext dc);
 230 }