ポリゴン

/*
*   JAVA3D でポリゴンを描くアプレット
*/

import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.GraphicsConfiguration;
import javax.media.j3d.*;
import javax.vecmath.*;
import com.sun.j3d.utils.universe.*;

/* <applet code="java3Dtest02" width=300 height=300></applet> */

public class java3Dtest02 extends Applet{
  private SimpleUniverse universe = null;

  public BranchGroup createSceneGraph(){
    BranchGroup root = new BranchGroup();

    TransformGroup trans = new TransformGroup();
    trans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    root.addChild(trans);

    Point3d[] verteces = new Point3d[4];

    verteces[0] = new Point3d(-0.5, 0.5, 0.0);
    verteces[1] = new Point3d(-0.5, -0.5, 0.0);
    verteces[2] = new Point3d(0.5, 0.5, 0.0);
    verteces[3] = new Point3d(0.5, -0.5, 0.0);

    int[] indeces = {0, 1, 2, 3};

    int[] triangleStripCounts = {4};

    Color3f[] colors = new Color3f[4];
    
    colors[0] = new Color3f(1.0f, 0.0f, 0.0f);
    colors[1] = new Color3f(0.0f, 1.0f, 0.0f);
    colors[2] = new Color3f(0.0f, 0.0f, 1.0f);
    colors[3] = new Color3f(1.0f, 1.0f, 0.0f);

    int[] color_indeces = {0, 1, 2, 3};

    IndexedTriangleStripArray geometry = new IndexedTriangleStripArray(verteces.length, GeometryArray.COORDINATES | GeometryArray.COLOR_3, indeces.length, triangleStripCounts);
    geometry.setCoordinates(0, verteces);
    geometry.setCoordinateIndices(0, indeces);
    geometry.setColors(0, colors);
    geometry.setColorIndices(0, color_indeces);

    Shape3D shape = new Shape3D(geometry);

    trans.addChild(shape);

    Alpha rotationAlpha = new Alpha(-1, 0);
    RotationInterpolator rotator = new RotationInterpolator(rotationAlpha, trans);

    root.addChild(rotator);

    root.compile();

    return root;
  }

  public void init() {
    GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();
    Canvas3D canvas3d = new Canvas3D(config);
    this.setLayout(new BorderLayout());
    this.add(canvas3d, BorderLayout.CENTER);

    BranchGroup scene = createSceneGraph();

    universe = new SimpleUniverse(canvas3d);

    universe.getViewingPlatform().setNominalViewingTransform();
    universe.addBranchGraph(scene);
  }

  public void destroy(){
    universe.cleanup();
  }
}