JPCT+odejava and Skybox

[Chico de las poeías]

Source:

http://laboratorio-jota.webcindario.com/Java+Odejava.rar
http://laboratorio-jota.webcindario.com/SkyBox.rar



What do you think?... 

[EgonOlsen]

Nice work. However, i had some trouble figuring out why the boxes in the ODE-example are actually moving until i realized that the rotation matrix you are using actually isn't a rotation matrix, but a combined transformation matrix. Without digging further into ODE or your code, i suggest to split the matrix into a rotational and a translational part somehow like so:

Code Select Expand


import com.threed.jpct.*;
import javax.swing.*;
import java.awt.*;
import javax.vecmath.Matrix4f;
import javax.vecmath.Quat4f;
import javax.vecmath.Vector3f;

/**
*
* @author Enrique Bermúdez E-mail: enbe11_3@hotmail.com
*/

public class JPCTODE {

   public static void main(String[] args) throws Exception {
       JPCTODE JO = new JPCTODE();
       JO.doIt();
   }

   private void doIt() throws Exception {

       JFrame frame = new JFrame();
       frame.setSize(640, 480);
       frame.setVisible(true);
       ODE ode = new ODE();

       FrameBuffer fb = new FrameBuffer(640, 480, FrameBuffer.SAMPLINGMODE_NORMAL);
       fb.enableRenderer(IRenderer.RENDERER_SOFTWARE);

       World w = new World();
       w.setAmbientLight(255, 255, 255);

       TextureManager tm = TextureManager.getInstance();
       Texture base = new Texture("top.jpg");
       tm.addTexture("base", base);
       Object3D box = Primitives.getCube(2.0F);

       box.setTexture("base");
       box.setEnvmapMode(box.ENVMAP_ENABLED);
       box.setEnvmapped(true);

       Object3D sp = Primitives.getCube(2.0F);
       sp.setTexture("base");
       sp.setEnvmapMode(box.ENVMAP_ENABLED);
       sp.setEnvmapped(true);

       sp.rotateY((float) Math.PI / 4f);
       sp.rotateMesh();
       box.rotateY((float) Math.PI / 4f);
       box.rotateMesh();
       w.addObject(sp);
       w.addObject(box);

       w.buildAllObjects();
       w.getCamera().moveCamera(Camera.CAMERA_MOVEOUT, 40);

       w.getCamera().lookAt(box.getCenter());
       w.addLight(new SimpleVector(30, 30, 03), 30, 30, 03);

       Matrix n = new Matrix();
       Matrix m = new Matrix();

       while (frame.isActive()) {

           n.setDump(getMatrix(ode.boxBody.getQuaternion(), ode.boxBody.getPosition(), 1.0f));
           m.setDump(getMatrix(ode.boxBody2.getQuaternion(), ode.boxBody2.getPosition(), 1.0f));
           ode.step();

           box.setRotationMatrix(extractRotation(n));
           sp.setRotationMatrix(extractRotation(m));
           
           box.setTranslationMatrix(extractTranslation(n));
           sp.setTranslationMatrix(extractTranslation(m));

           fb.clear(new Color(200, 200, 200));
           w.renderScene(fb);
           w.draw(fb);

           fb.display(frame.getGraphics());
           Thread.sleep(30);
       }

       fb.disableRenderer(IRenderer.RENDERER_OPENGL);
       System.exit(0);
   }

   private Matrix extractRotation(Matrix m) {
     Matrix m2=m.cloneMatrix();
     m2.set(3, 0, 0);
     m2.set(3, 1, 0);
     m2.set(3, 2, 0);
     m2.set(3, 3, 1);
     return m2;
   }
   
   private Matrix extractTranslation(Matrix m) {
     Matrix m2=m.cloneMatrix();
     m2.set(0, 0, 1);
     m2.set(1, 1, 1);
     m2.set(2, 2, 1);
     
     m2.set(1, 0, 0);
     m2.set(2, 0, 0);
     m2.set(2, 1, 0);
     
     m2.set(0, 1, 0);
     m2.set(0, 2, 0);
     m2.set(1, 2, 0);
     
     return m2;
   }
   
   private float[] getMatrix(Quat4f q, Vector3f v, float f) {

       Matrix4f m = new Matrix4f(q, v, f);

       return new float[]{m.m00, m.m10, m.m20, m.m30,
                   m.m01, m.m11, m.m21, m.m31,
                   m.m02, m.m12, m.m22, m.m32,
                   -m.m03, -m.m13, -m.m23, m.m33
               };
   }
}



Giving jPCT a rotation matrix to work with that actually isn't one may bite you sooner or later...

[Chico de las poeías]

Thanks!



PD:
Oviusly, you can also work with diferents shapes.
For example:
   
ODE.java:   
   

boxBody2 = new Body("box2", world, new GeomSphere("esfera",2f));

JPCTODE.java:
   

Object3D sp = Primitives.getSphere(2.0F);

   
(if anybody wants odejava supports, you can find it here: http://www.javagaming.org/ )