Java3D is a specification for generation and manipulation of three-dimensional objects. It is based on the scene graph concept, which relies on tree-oriented structures. So you have an intuitive feasibility to realize 3D scenes in the object-oriented world of the Java programming language. The basic objects of Java3D are:
- BranchGroup: Defines a group of 3D-based shapes, transformations, lights, appearances, ... Could be a child of another BranchGroup-object
- TransformGroup: Defines a transformation how rotation, translation and scaling.
- Shape3D: geometrical 3D objects (Box, ColorCube, Cylinder,...).
- Behavior: Root interface for handling input devices how mouse, keyboard, joystick.
- Light: All possible light types (ambient, direct, ...).
The example above describes a scene graph, which consists of 10x10x10 boxes. It is based on the following scene graph.
package org.developers.blog.graph3d;
import com.sun.j3d.utils.behaviors.keyboard.KeyNavigatorBehavior;
import com.sun.j3d.utils.behaviors.mouse.MouseRotate;
import com.sun.j3d.utils.geometry.*;
import com.sun.j3d.utils.universe.*;
import java.awt.Color;
import javax.media.j3d.*;
import javax.vecmath.*;
/**
* Hello world!
*
*/
public class Java3DExample {
private SimpleUniverse universe;
private Appearance cubeAppearance;
private BranchGroup rootGroup;
private BoundingSphere bounds;
public void init() {
createUniverse();
createAppearance();
createCubeOfCubes();
createLights();
createBehaviourInteractors();
universe.getViewingPlatform().setNominalViewingTransform();
// add the cube group of objects to SimpleUnvirse object
universe.addBranchGraph(rootGroup);
}
private void createUniverse() {
universe = new SimpleUniverse();
rootGroup = new BranchGroup();
bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
}
private void createAppearance() {
cubeAppearance = new Appearance();
Color3f ambientColour = new Color3f();
ambientColour.set(Color.GRAY);
Color3f emissiveColour = new Color3f(0.0f, 0.0f, 0.0f);
Color3f specularColour = new Color3f(1.0f, 1.0f, 1.0f);
Color3f diffuseColour = new Color3f();
diffuseColour.set(Color.GRAY);
float shininess = 20.0f;
cubeAppearance.setMaterial(new Material(ambientColour, emissiveColour,
diffuseColour, specularColour, shininess));
}
private void createCubeOfCubes() {
// build up a cube of 10 cube for each axis (x, y, z)
for (float x = -.5f; x <= .5f; x = x + .1f) {
for (float y = -.5f; y <= .5f; y += .1f) {
for (float z = -.5f; z <= .5f; z += .1f) {
Box box = new Box(0.02f, 0.02f, 0.02f, cubeAppearance);
TransformGroup tg = new TransformGroup();
Transform3D transform = new Transform3D();
Vector3f vector = new Vector3f(x, y, z);
transform.setTranslation(vector);
tg.setTransform(transform);
tg.addChild(box);
rootGroup.addChild(tg);
}
}
}
}
private void createLights() {
Color3f ambientLightColour = new Color3f(0.9f, 0.9f, 0.9f);
AmbientLight ambientLight = new AmbientLight(ambientLightColour);
ambientLight.setInfluencingBounds(bounds);
Color3f directionLightColour = new Color3f(1.0f, 1.0f, 1.0f);
Vector3f directionLightDir = new Vector3f(-1.0f, -1.0f, -1.0f);
DirectionalLight directionLight = new DirectionalLight(directionLightColour, directionLightDir);
directionLight.setInfluencingBounds(bounds);
rootGroup.addChild(ambientLight);
rootGroup.addChild(directionLight);
}
private void createBehaviourInteractors() {
TransformGroup viewTransformGroup =
universe.getViewingPlatform().getViewPlatformTransform();
KeyNavigatorBehavior keyInteractor =
new KeyNavigatorBehavior(viewTransformGroup);
BoundingSphere movingBounds = new BoundingSphere(new Point3d(0.0, 0.0,
0.0), 100.0);
keyInteractor.setSchedulingBounds(movingBounds);
rootGroup.addChild(keyInteractor);
MouseRotate behavior = new MouseRotate();
behavior.setTransformGroup(viewTransformGroup);
rootGroup.addChild(behavior);
behavior.setSchedulingBounds(bounds);
}
public static void main(String[] args) {
(new Java3DExample()).init();
}
}
Regards
Rafael Sobek
Technorati Tags: Java3D
Very nice! Java3D depends on openGL for hardware acceleration, right?