User:
OSP Moviomeinto de Figuras 3D
Description 
En el caso de la pelota que rebota se puede emplear el código:
```
/**
* www.opensourcephysics.org/
* @author Wolfgang Christian
*/
import org.opensourcephysics.controls.AbstractSimulation;
import org.opensourcephysics.display3d.simple3d.*;
public class BounceApp extends AbstractSimulation {
DrawingPanel3D panel = new DrawingPanel3D();
DrawingFrame3D frame = new DrawingFrame3D(panel);
Element ball = new ElementEllipsoid();
Element floor = new ElementBox();
double velocity = 0;
public BounceApp() {
panel.setPreferredMinMax(-5, 5, -5, 5, 0, 10);
ball.setXYZ(0.0, 0.0, 9.0);
ball.setSizeXYZ(2, 2, 2);
ball.getStyle().setFillColor(java.awt.Color.YELLOW);
// floor
floor.setXYZ(0.0, 0.0, 0.0);
floor.setSizeXYZ(5.0, 5.0, 1.0);
// Add the objects to panel
panel.addElement(ball);
panel.addElement(floor);
frame.setDefaultCloseOperation(javax.swing.JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
protected void doStep() {
double z = ball.getZ(), dt = 0.05;
z += velocity*dt; // moves the ball
velocity -= 9.8*dt; // acceleration changes the velocity
if(z<=1.0&&velocity<0) {
velocity = -velocity;
}
ball.setZ(z);
}
public static void main(String[] args) {
(new BounceApp()).startSimulation();
}
}
```
ID:(8764, 0)