Posted by wenlinm on Jun 05, 2019; 9:38am
URL: https://forum.jogamp.org/Java3d-Nothing-is-Rendered-tp4039834.html

Hi everyone,

I currently received a job to fix a project that was developed 15 years ago and was still running 2 years ago. It was using an ancient version of Java3d 1.5.2 before and it is no longer work on the Mac OSX. So I ported this project to Java3d 1.6.0 from here and Java 1.8.

The problem is that everything works fine with no warning or errors but only a black background is rendered in the window.

I attached the code I used to test. It should render a color cube however nothing is actually rendered. Only a window with black background is shown.

I am new to Java3d so please correct me if I am wrong. I feel the problem happens with the GraphicsContext3D's draw method as I tried with several different test code snippet and only the code uses GraphicsContext3D failed to render. However, I have no idea how to fix this problem without changing the structure too much.

I tried this project on both Mac Mojave, High Sierra, and El Capitan but none of the operating system worked.

Any suggestion would be helpful. Thanks in advance.

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import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.GraphicsConfiguration;

import javax.media.j3d.Alpha;
import javax.media.j3d.Appearance;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.Geometry;
import javax.media.j3d.GraphicsContext3D;
import javax.media.j3d.Transform3D;

import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.ColorCube;
import com.sun.j3d.utils.universe.SimpleUniverse;

/**
 * Pure immediate mode example program. In pure immediate mode, the renderer
 * must be stopped on the Canvas being rendered into. In our example, this is
 * done immediately after the canvas is created. A separate thread is started up
 * to do the immediate mode rendering.
 */
public class PureImmediate extends Applet implements Runnable {

    private Canvas3D canvas;

    private GraphicsContext3D gc = null;

    private Geometry cube = null;

    private Transform3D cmt = new Transform3D();

    // One rotation (2*PI radians) every 6 seconds
    private Alpha rotAlpha = new Alpha(-1, 6000);

    private SimpleUniverse u = null;

    //
    // Renders a single frame by clearing the canvas, drawing the
    // geometry, and swapping the draw and display buffer.
    //
    public void render() {
        if (gc == null) {
            // Set up Graphics context
            gc = canvas.getGraphicsContext3D();
            gc.setAppearance(new Appearance());

            // Set up geometry
            cube = new ColorCube(0.4).getGeometry();
        }

        // Compute angle of rotation based on alpha value
        double angle = rotAlpha.value() * 2.0 * Math.PI;
        cmt.rotY(angle);

        // Render the geometry for this frame
        gc.clear();
        gc.setModelTransform(cmt);
        gc.draw(cube);
        canvas.swap();
    }

    //
    // Run method for our immediate mode rendering thread.
    //
    public void run() {
        System.out.println("PureImmediate.run: starting main loop");
        while (true) {
            render();
            Thread.yield();
        }
    }

    public PureImmediate() {
    }

    //
    // init: create the canvas, stop the renderer,
    // create the universe, and start the drawing thread.
    //
    public void init() {
        setLayout(new BorderLayout());
        GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();

        canvas = new Canvas3D(config);
        canvas.stopRenderer();
        add("Center", canvas);

        // Create the universe and viewing branch
        u = new SimpleUniverse(canvas);

        // This will move the ViewPlatform back a bit so the
        // objects in the scene can be viewed.
        u.getViewingPlatform().setNominalViewingTransform();

        // // Start a new thread that will continuously render
        new Thread(this).start();
    }

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

    //
    // The following allows PureImmediate to be run as an application
    // as well as an applet
    //
    public static void main(String[] args) {
        System.setProperty("sun.awt.noerasebackground", "true");
        new MainFrame(new PureImmediate(), 256, 256);

    }
}