Here's what I've got so far with adapting Dr. Alden's code. A UI class that handles displaying the canvas and a World class that handles the objects in the world. Neither are complete. I'll pick this up tomorrow.

I have a feeling we're going to have class path issues with the j3d libaries between our computers. I'll test between my desktop and Mac. If so, I'll drop the JARs for the java3d in the project and import them that way.

1 files changed, 154 insertions, 0 deletions

diff --git a/src/tesseract/World.java b/src/tesseract/World.java
new file mode 100644
index 0000000..e7555a5
--- /dev/null
+++ b/src/tesseract/World.java
@@ -0,0 +1,154 @@
+package tesseract;
+
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+
+import javax.media.j3d.BoundingBox;
+import javax.media.j3d.BoundingSphere;
+import javax.media.j3d.BranchGroup;
+import javax.media.j3d.DirectionalLight;
+import javax.media.j3d.IndexedLineArray;
+import javax.media.j3d.Light;
+import javax.media.j3d.Node;
+import javax.media.j3d.Shape3D;
+import javax.vecmath.Color3f;
+import javax.vecmath.Point3d;
+import javax.vecmath.Vector3f;
+
+public class World {
+	/**
+	 * Root element of the world.
+	 */
+	private BranchGroup myScene;
+	
+	/**
+	 * Bounding box of the world.
+	 */
+	private BoundingBox myVirtualWorldBounds;
+	
+	/**
+	 * A list of the objects in the world. 
+	 */
+	private List<Particle> myObjects;
+	
+	/**
+	 * A list of the forces in the world.
+	 */
+	private List<Force> myForces;
+	
+	//private List<ParticleEmitter> emitters;
+	//private boolean enableEmitters;
+	
+	// A list of all the particles in the world
+	//private List<Particle> particles;
+	
+	// A list of all the objects particles may collide with
+	//private List<ParticleCollidableObject> collidables;
+	
+	// Available forces
+	//private static final ParticleForceGenerator forces[] = {new Gravity(0.4f)};
+	//private boolean activeForces[];
+	
+	// Number of state updates per second
+	//private final int UPDATE_RATE = 30;
+	
+	public World(final BoundingBox bounds) {
+		myVirtualWorldBounds = bounds;
+
+		myForces = new LinkedList<Force>();
+		myObjects = new LinkedList<Particle>();
+		
+		// TODO: Should this go here?
+		myScene = new BranchGroup();
+		myScene.setCapability(BranchGroup.ALLOW_CHILDREN_EXTEND);
+		myScene.setCapability(BranchGroup.ALLOW_CHILDREN_WRITE);
+		myScene.addChild(createVirtualWorldBoundsShape());
+		addLights();
+		addEmitters();
+		addCollidableObjects();
+		myScene.compile();
+	}
+
+	
+
+	private Node createVirtualWorldBoundsShape() {
+		Point3d lower = new Point3d();
+		Point3d upper = new Point3d();
+		virtualWorldBounds.getLower(lower);
+		virtualWorldBounds.getUpper(upper);
+		
+		double coordinates[] = {lower.x, lower.y, lower.z, upper.x, lower.y, lower.z,
+		                       upper.x, lower.y, upper.z, lower.x, lower.y, upper.z,
+		                       lower.x, upper.y, lower.z, upper.x, upper.y, lower.z,
+		                       upper.x, upper.y, upper.z, lower.x, upper.y, upper.z};
+		int coordinateIndices[] = {0, 1, 1, 2, 2, 3, 3, 0,
+		                           4, 5, 5, 6, 6, 7, 7, 4,
+		                           0, 4, 1, 5, 2, 6, 3, 7}; 
+		
+		IndexedLineArray geometry = new IndexedLineArray(coordinates.length / 3, IndexedLineArray.COORDINATES, coordinateIndices.length);
+		geometry.setCoordinates(0, coordinates);
+		geometry.setCoordinateIndices(0, coordinateIndices);
+		
+		return new Shape3D(geometry);
+	}
+
+	private void addLights() {
+		Light light = new DirectionalLight(new Color3f(1f, 1f, 1f), new Vector3f(-1f, -1f, -1f));
+		light.setInfluencingBounds(new BoundingSphere(new Point3d(0, 0, 0), 10));
+		scene.addChild(light);
+		light = new DirectionalLight(new Color3f(0.3f, 0.1f, 0.1f), new Vector3f(1f, 0f, 0f));
+		light.setInfluencingBounds(new BoundingSphere(new Point3d(0, 0, 0), 10));
+		scene.addChild(light);
+	}
+	
+	private void addEmitters() {
+		emitters.add(new ColorShiftParticleEmitter(new Vector3f(-0.2f, 0.5f, 0)));
+	}
+
+	private void addCollidableObjects() {
+		collidables.add(new Circle(0.25f, new Vector3f(-0.2f, 0.3f, 0), new Vector3f(0.6f, 1, 0)));
+		collidables.add(new Circle(0.25f, new Vector3f(0.2f, 0.1f, 0), new Vector3f(-0.6f, 1, 0)));
+		collidables.add(new Circle(0.25f, new Vector3f(-0.2f, -0.1f, 0), new Vector3f(0.6f, 1, 0)));
+		collidables.add(new Circle(0.25f, new Vector3f(0.2f, -0.3f, 0), new Vector3f(-0.6f, 1, 0)));
+		
+//		collidables.add(new Circle(0.25f, new Vector3f(0.15f, 0, 0), new Vector3f(0.02f, 1, 0)));
+//		collidables.add(new MathMesh(new Vector3f(0.13f, 0, 0), 151));
+		for (ParticleCollidableObject object : collidables)
+			scene.addChild(object.getGroup());
+	}
+
+	public void tick() {
+		for (Iterator<Particle> itr = particles.iterator(); itr.hasNext();) {
+			Particle particle = itr.next();
+			for (int i = 0; i < forces.length; i++)
+				if (activeForces[i])
+					forces[i].applyForceTo(particle);
+			particle.updateState(1f / UPDATE_RATE);
+			for (ParticleCollidableObject object : collidables) {
+				CollisionInfo ci = object.calculateCollision(particle);
+				if (ci != null)
+					object.resolveCollision(particle, ci);
+			}
+			if (!virtualWorldBounds.intersect(new Point3d(particle.getPosition()))) {
+				particle.detach();
+				itr.remove();
+			}
+		}
+		if (!enableEmitters)
+			return;
+		for (ParticleEmitter emitter : emitters) {
+			List<Particle> children = emitter.tick();
+			for (Particle particle : children)
+				scene.addChild(particle.getGroup());
+			particles.addAll(children);
+		}
+	}
+	
+	/**
+	 * @return the root BG of the scene.
+	 */
+	public BranchGroup getScene() {
+		return myScene;
+	}
+}