universemanager.java

Java 3D Desktop Environment旨在使用Java 3D来创建一个3D桌面环境。功能包括：分布式的应用程序

package org.j3de.ui.impl;   
 
import java.util.List;
        
import javax.media.j3d.Behavior;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;  
import javax.media.j3d.Group;
import javax.media.j3d.InputDevice;        
import javax.media.j3d.Locale;        
import javax.media.j3d.Node;        
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment; 
import javax.media.j3d.View; 
import javax.media.j3d.ViewPlatform;
import javax.media.j3d.VirtualUniverse; 
 
import org.j3de.interfaces.Environment;

public class UniverseManager extends VirtualUniverse {  
  private static UniverseManager manager;
    
  private Locale      locale;     
  private Canvas3D    canvas3d;
  
  private View        view;
  private PhysicalEnvironment env;
  private BranchGroup world_object_group;
  private BranchGroup world;
  private BranchGroup behaviors;    
  private int         minimumFrameCycleTime;
  
  public UniverseManager(Canvas3D canvas3d, List devices, int maxFrames) { 
    manager = this;
    this.canvas3d = canvas3d;
    view = new View();
    view.addCanvas3D(canvas3d); 
    
    locale = new Locale(this); 
    
    behaviors = new BranchGroup();
    behaviors.setCapability(Group.ALLOW_CHILDREN_WRITE);
    behaviors.setCapability(Group.ALLOW_CHILDREN_EXTEND);     
     
    world_object_group = new BranchGroup();
    world_object_group.setCapability(Group.ALLOW_CHILDREN_READ);
    world_object_group.setCapability(Group.ALLOW_CHILDREN_WRITE);
    world_object_group.setCapability(Group.ALLOW_CHILDREN_EXTEND);     
    
    world_object_group.addChild(behaviors);
    locale.addBranchGraph(world_object_group);     
    
    if (maxFrames != 0)
      minimumFrameCycleTime = 1000 / maxFrames; 
    else    
      minimumFrameCycleTime = 0;
  
    int sensorCount = 0;
    for (int i=0; i<devices.size(); i++)
      sensorCount += ((InputDevice)devices.get(i)).getSensorCount();
      
    env      = new PhysicalEnvironment(sensorCount);  
    int sensorIndex = 0;
    for (int i=0; i<devices.size(); i++) {
      InputDevice device = (InputDevice)devices.get(i); 
      env.addInputDevice(device);     
      
      for (int j=0; j<device.getSensorCount(); j++) {
        env.setSensor(sensorIndex, device.getSensor(j));
        sensorIndex++;
      }
    }
     
    view.setPhysicalEnvironment(env);
  }    
   
  public void setEnvironment(Environment environment) {          
    
    if (world != null) {
      for (int i=0; i<world_object_group.numChildren(); i++) {
       if (world_object_group.getChild(i) == world)
         world_object_group.removeChild(i);                             
      }             
    }  
    
    world = environment.getWorldObject();
    
    if (!world.isCompiled())
      world.setCapability(BranchGroup.ALLOW_DETACH);
      
    world.compile();    
    
    // This will affect framerate, even if minimumFrameCycleTime is much higher than
    // current frame cycle time. If it is 0 : don't set it at all ...
    if (minimumFrameCycleTime != 0) 
      view.setMinimumFrameCycleTime(minimumFrameCycleTime);  
    
    synchronized (world) {    
      world_object_group.addChild(world);    
    }
    
    view.setPhysicalBody(environment.getPhysicalBody());    
    view.attachViewPlatform(environment.getViewPlatform());
  }
  
  public void addBehavior(Behavior behavior) {
    BranchGroup bg = new BranchGroup();
    bg.addChild(behavior);  
    bg.compile();
    behaviors.addChild(bg);
  }
}