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1.1 Strengths

The foremost strength of Java 3D for Java developers is that it allows them to program in 100 percent Java. In any sizeable 3D application, the rendering code will compose only a fraction of the total application. It is therefore very attractive to have all the application code, persistence, and user interface (UI) code in an easily portable language, such as Java. Although Sun’s promise of Write−Once−Run−Anywhere is arguably more of a marketing dream than a reality, especially for client−side programming, Java has made important inroads toward enabling application developers to write applications that can be easily moved between platforms. The platforms of most interest today are Microsoft Windows 98/NT/2000, Sun Solaris, LINUX, and Macintosh OS X.


Java has arguably become the language of networked computing and the Internet. High−level support for remote method invocation (RMI), object serialization, platform independent data types, UNICODE string encoding, and the security model all provide persuasive arguments for adopting the Java language for applications that are increasingly gravitating away from a desktop−centric worldview. Many of the state−of−the−art 3D graphics applications being built with Java 3D today are leveraging the strengths of Java as a language for the Internet.


The Java 3D API itself has much to offer the application developer. By allowing the programmer to describe the 3D scene using coarser−grained graphical objects, as well as by defining objects for elements such as appearances, transforms, materials, lights, and so forth, code is more readable, maintainable, reusable, and easier to write. Java 3D uses a higher level scene description model, the scenegraph, which allows scenes to be easily described, transformed, and reused.


Java 3D includes a view model designed for use with head−mounted displays (HMDs) and screen projectors. By insulating the programmer from much of the complex trigonometry required for such devices, Java 3D eases the transition from a screen−centric rendering model to a projected model, where rendering in stereo allows for greater realism.


Java 3D also includes built−in support for sampling 3D input devices and rendering 3D spatial sound. By combining all of the above elements into a unified API, Java 3D benefits from a uniformity of design that few other APIs can match.


Java 3D’s higher level of abstraction from the mechanics of rendering the scene have also opened the field of interactive 3D graphics to a new class of audience, people who would typically have been considered 3D content creators. Think of 3D graphics creation as a spectrum, with resources and talents distributed across a variety of tasks, as illustrated in figure 1.1.

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Figure 1.1 Java 3D fills an important gap between VRML, which is centered around describing 3D content, and OpenGL, which is a C API for rendering points, lines, and triangles

Many new programmers have moved from Virtual Reality Modeling Language (VRML) into Java 3D. They are 3D content creation specialists; and they require the greater flexibility offered by a programming API, though they are reluctant to learn OpenGL and C. For this audience, Java 3D fills an important niche, allowing them to concentrate on content creation and application logic, without choking on the details of rendering and arcane programming syntax.