V M e c h . c o m
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Fighting immechanacy on the Web

Site Map

  1. Introduction
  2. Java3D Models
    1. Sun's HelloUniverse
    2. Simple Crank
    3. Crank Rocker
    4. Drag Link
    5. Four Bar Linkage Beta
  3. Papers (in progress)
    1. Machines in Java3D
    2. Inverse Kinematics on the Scene Graph
    3. Simulations on the Web
    4. 'Time' in Java3D
  4. Appendices

A.     Installing the Java2 Plug-in and Java3D

B.     Security and Java applets

  1. References
  2. About VMech.com

Appendix A Installing the Java2 Plug-in and Java3D

Contents:

Note: See also the Java3D FAQ at www.j3d.org. The latest version of the Java3D installation instructions for Users (people who just want to view Java3D applets on the web or downloaded applications) and for Developers (people who want to write and deploy Java programs) are at http://www.j3d.org/installing.html.

A.1 Background

The applets presented on this site were created using Java2 with the Java3D optional extension, so to view them, you must have installed on your computer the following software:

  • Operating system. Unix, Linux?, Windows NT4.0 (no 3.5), Windows 95, 98, 2000. No Mac?
  • A browser (Microsoft Internet Explorer 4.0 or later or Netscape Communicator 4.0 or later)
  • Sun's Java2 support. When they come from the manufacturer, the browsers listed above can run only 'old' Java (without the '2') applets (produced by Java Development Kits JDK1.0 and JDK1.1, not that you have to care, but a lot of the stuff written in FAQs and installation instructions assumes that you do.) Running Java2 applets (developed using JDK 1.2 or later) requires that you install a browser "Plug-in" on your computer.

    The Plug-in is a browser add-in that is part of the Java Runtime Environment (JRE), and it is installed and set up at the same time that you install the JRE. For more information, try Sun's Plug-in     FAQ. Unfortunately, it buries what you need to know under piles of stuff written for developers. Sun also provides a plug-in troubleshooting FAQ here.
  • Sun's Java3D support. Java3D is not a part of what's called 'core Java.' Rather, it's an 'extension,' and the standard JRE (including the standard Plug-in) won't run Java3D applets unless the Java3D extension files are installed on your computer. General installation notes are here.

    Unfortunately, some versions of Sun-supplied installation software may place Java3D extension files in a folder where the Plug-in can't find them. The instructions for installation of Windows listed below are intended to avoid those potential problems.
  • OpenGL support. If you have early Windows95, you have to download and install support from here. OpenGL is a mid-level graphics language that Java3D needs for communication with your computer graphics hardware, and support for it must be provided on your computer. Here's what the OpenGl.org says about Windows: "Windows NT v4.0, Windows 2000, Windows 98, and Windows 95 (OSR2) all ship with OpenGL v1.1, so if you are using one of these operating systems, you're all set." There are other options for Windows 2000, but for that you're on your own.

A.2 Windows Installation Sequence for Users

Here are installation instructions (applicable in August 2000, when the JRE is at 1.3.0 and the Java3D is at 1.2) for Windows 95, Windows 95 (OSR2), Windows 98, Windows 2000, Windows NT4.0. The details are for Windows NT. Email me with suggestions for details on other OSs.

Windows (except original Windows 95)

  1. Download the 'Java(TM) 2 Runtime Environment 1.3.0' installation file from Sun's Java2 Plug-in page. In early August 2000, the file name is j2re1_3_0-win.exe = 5,088,456 bytes.
  2. Download the 'Java 3D Windows Runtime for the JRE' from Sun's Java3D page. In early August 2000, the file name is java3d-1_2-win-opengl-rt.exe = 2,237,931 bytes.
  3. Install the Java2 Runtime Environment (includes the browser Plug-in) by executing j2re1_3_0-win.exe. Installation is automatic. The installation should offer the default folder: C:\Program Files\Javasoft\JRE\1.3.
  4. Check the 'Java (TM) Plug-in Properties' by examining Start->Settings->Control Panel->Java Plug-in->About. Verify that the default Virtual Machine Version is 1.3.0. Click Basic tab on panel. Check all boxes.
  5. Test the Java2 Plug-in installation by running demo applets.
  6. Install the Java3D support by running java3d-1_2-win-opengl-rt.exe. The installation may offer to install 3D in C:\Program Files\JavaSoft\JRE\1.2. Don't do it. Click the 'Browse' button, find, and select the folder into which you installed the Plug-in in step 3. above - probably
    C:\Program Files\Javasoft\JRE\1.3.    )
  7. Check the directory structure. It should look something like this:

    C:\Program Files\JavaSoft\JRE\1.3
    - bin <===========    (note 1)
    - - hotspot
    - lib
    - - applet
    - - cmm
    - - ext <=========    (note 2)
    - - fonts
    - - images
    - - - cursors
    - - security

    note 1: Java3D files J3D.dll and j3daudio.dll should appear here.

    note 2: Java3D files     j3daudio.jar, j3dcore.jar, j3dutils.jar, and vecmath.jar should appear here.
  8. Test the installation by running a copy of Sun's HelloUniverse demo here.
  9. Test the installation by running the VMech Simple Crank demo.

A.3 If It Still Doesn't Work

  • Black screen with no messages
    • Browser security settings. In order to run Java applets, you must have scripting enabled in your browser.
      • To check whether scripting is enabled on Microsoft Internet Explorer, on its menu click Tools -> Internet Options -> Security -> Internet -> Custom Level -> Run ActiveX Controls and plug-ins. Check Enable or Prompt.
      • I admit it. I frankly don't understand the way that security defaults are set in Netscape Navigator. Evidently by default, Java applets are enabled in Navigator. Eventually, I'll provide signed security for my site, but I don't understand that process well enough to explain it to anyone else.
    • Firewalls. Some corporate or office computer networks are protected from outside (Internet) attack by 'firewalls' - software that reads and analyzes network traffic, and identifies viruses or other security threats. Firewalls may grant or deny access for Java applets. Ask your system administrator about security settings. If you are the system administrator, I can't offer any help other than RTFM. ( Many thanks to Carl Smotricz for debugging his firewall and reporting his success.)
  • Messages:
    • "WARNING: Canvas3D constructed with a null GraphicsConfiguration" in the Java Console when an applet starts. Ignore it. This is a normal condition for any applet that builds on one of Sun's demonstration programs.

Return to the Introduction.

Last revision
December 7, 2000
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