java多容器加载Java3D

Question

我正在尝试使用Java3D为多容器装载问题创建一个3D界面

我想将每个容器和已经包装在其中的物品分别显示在不同的框架中。（例如，如果我有3个容器，将有3个不同的框架）

在容器的类中，我添加了BranchGroup变量：

 private static BranchGroup scene ; 

在构造函数中，我创建了BranchGroup场景和一个框架（我将发布上面的接口类）

public ContainerW(final int iD) {
        super();
        cRef = iD;
        this.emptyBreadth = 0;
        this.length = 0.8;
        this.height = 0.6;
        this.breadth = 0.5 - emptyBreadth;
        this.usedVolume = 0;
        volume = length * breadth * height;
        this.packedItems = new ArrayList<ItemsUnit>();
        scene = new BranchGroup();
        Frame frame = new MainFrame(new Interface(scene),800, 800); 

    }

打包新项目时，我添加以下内容（我将新节点添加到BranchGroup场景）：

  scene.addChild(Interface.addItem(item[p].getLength(), item[p].getBreadth(), item[p].getBreadth(), x, y, z));

（x、y和z是翻译参数）

在Interface类中，我编写了一个方法来创建框架并在其中绘制容器，以及另一个方法来添加项目的3DNode

package Interface3D;
import java.applet.Applet;
import java.awt.BorderLayout;
import javax.media.j3d.Appearance;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.PolygonAttributes;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.TransparencyAttributes;
import javax.vecmath.AxisAngle4d;
import javax.vecmath.Vector3f;
import com.sun.j3d.utils.geometry.Box;
import com.sun.j3d.utils.universe.SimpleUniverse;
import Classes.ContainerW;

public class Interface extends Applet{


    public Interface(BranchGroup scene) {


         this.setLayout(new BorderLayout());
           Canvas3D canvas3D = new Canvas3D(SimpleUniverse.getPreferredConfiguration());
            this.add(canvas3D, BorderLayout.CENTER);

            SimpleUniverse simpleU = new SimpleUniverse(canvas3D);
            simpleU.getViewingPlatform().setNominalViewingTransform();

        //create an appearance for the container
        Appearance app = new Appearance();
        //Create the polygon attributes
        PolygonAttributes polyAttr = new PolygonAttributes();
        //Set them so that the draw mode is polygon line
        polyAttr.setPolygonMode(PolygonAttributes.POLYGON_LINE);
        polyAttr.setCullFace(PolygonAttributes.CULL_NONE);
        //Use these in the appearance
        app.setPolygonAttributes(polyAttr);

        //rotate the view angle 
        Transform3D rotateCube = new Transform3D();
        rotateCube.set(new AxisAngle4d(1.0, 1.0, 0.0, Math.PI /4.0));

        //create a transform Group for the container
        TransformGroup tg1 = new TransformGroup(rotateCube);
        tg1.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);

        //create a box: container
        Box container = new Box ( (float) ContainerW.getLength() , (float) ContainerW.getBreadth(), (float) ContainerW.getHeight(), app);

        //add the container to the first transform group
        tg1.addChild(container);

        //add the first transform group to the branch group
        scene.addChild(tg1);

        scene.compile();

        simpleU.addBranchGraph(scene);


    }





       /**
        * adding an item box into the container in the position (x, y, z)
        * @param x
        * @param y
        * @param z
        */
       public static TransformGroup addItem(double l, double b, double h, double x, double y, double z) {

           TransformGroup tg2 = new TransformGroup ();
           //set the appearance of the product boxes (transparent) 
           Appearance app = new Appearance(); 
           app.setTransparencyAttributes(new TransparencyAttributes(TransparencyAttributes.BLENDED,0.2f));
           //create a box having length = l, breadth = b and height = h
           Box box = new Box( (float )l, (float)  b, (float) h, app);

           // vector to translate the item box to the position (x, y, z)
           Vector3f position = new Vector3f((float) x, (float) y, (float) z);
           //creation of a 3D transform group
           Transform3D transform = new Transform3D();
           transform.setTranslation(position);
           tg2.setTransform(transform);
           //add new item box to the transform group
           tg2.addChild(box);   

           return tg2;

         } 
}

运行该程序时，我得到多个框架，其中绘制了容器，但没有项目

我知道我的问题在分支组scene，因为我得到了以下错误：

javax.media.j3d.RestrictedAccessException: Group: only a BranchGroup node may be added   

因为这条线：

scene.addChild(Interface.addItem(item[p].getLength(), item[p].getBreadth(), item[p].getBreadth(), x, y, z));

我试着用scene.detach()来解决这个问题，但没有任何改变（可能是这样）

我将分离方法放错了位置，我不确定）

有人知道如何创建多个场景，在每个场景中我都会绘制容器和包装物品吗

我希望你能理解我的问题

我不能在这里发布完整的代码和所有的类，因为它太复杂了

多谢各位

Answer 1

因此，我所做的工作如下：

我制作了BranchGroup场景1、画布和宇宙全局变量：

private static SimpleUniverse simpleU ;
private static Canvas3D canvas3D;
private static BranchGroup scene1;

我在容器的类构造函数中创建了3D接口：

public ContainerW(final int iD) {

    super();
    cRef = iD;
    this.emptyBreadth = 0;
    this.length = 0.8;
    this.height = 0.6;
    this.breadth = 0.5 - emptyBreadth;
    this.usedVolume = 0;
    volume = length * breadth * height;
    this.packedItems = new ArrayList<ItemsUnit>();


    //           INTERFACE              

        this.setLayout(new BorderLayout());

        //create a canvas3D
        canvas3D = new Canvas3D(SimpleUniverse.getPreferredConfiguration());
        this.add(canvas3D, BorderLayout.CENTER);

        //create a universe
        simpleU = new SimpleUniverse(canvas3D);
        simpleU.getViewingPlatform().setNominalViewingTransform();

        //create a branch group scene 
        scene1 = new BranchGroup();


       //create an appearance for the container
        Appearance app = new Appearance();
        //Create the polygon attributes
        PolygonAttributes polyAttr = new PolygonAttributes();
        //Set them so that the draw mode is polygon line
        polyAttr.setPolygonMode(PolygonAttributes.POLYGON_LINE);
        polyAttr.setCullFace(PolygonAttributes.CULL_NONE);
        //Use these in the appearance
        app.setPolygonAttributes(polyAttr);

        //rotate the view angle 
        Transform3D rotateCube = new Transform3D();
        rotateCube.set(new AxisAngle4d(1.0, 1.0, 0.0, Math.PI /4.0));

        //create a transform Group for the container
        TransformGroup tg1 = new TransformGroup(rotateCube);
        tg1.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);

        //create a box: container
        Box container = new Box ( (float) length , (float) breadth, (float)height, app);

        //add the container to the first transform group
        tg1.addChild(container);

        //add the first transform group to the branch group
        scene1.addChild(tg1);

        scene1.setCapability(BranchGroup.ALLOW_CHILDREN_EXTEND);

        scene1.compile();

        simpleU.addBranchGraph(scene1);


       Frame frame = new MainFrame(this,800, 800); 


}

每添加一个新项目，我就会创建另一个分支组scene，并将其添加到全局分支组scene1，如下所示：

            TransformGroup tg2 = new TransformGroup ();
               //set the appearance of the product boxes (transparent) 
               Appearance app = new Appearance(); 
               app.setTransparencyAttributes(new TransparencyAttributes(TransparencyAttributes.BLENDED,0.2f));
               //create a box having length = l, breadth = b and height = h
               Box box = new Box( (float )item[p].getLength(), (float) item[p].getBreadth(), (float) item[p].getHeight(), app);

               // vector to translate the item box to the position (x, y, z)
               Vector3f position = new Vector3f((float) x, (float) y, (float) z);
               //creation of a 3D transform group
               Transform3D transform = new Transform3D();
               transform.setTranslation(position);
               tg2.setTransform(transform);
               //add new item box to the transform group
               tg2.addChild(box);
               tg2.setCapability(Group.ALLOW_CHILDREN_EXTEND);
               BranchGroup scene = new BranchGroup();
               scene.addChild(tg2);
               scene1.addChild(scene);

现在，我把集装箱和包装好的东西都放进了镜框里