CHAPTER 9
Working With Mobile 3D Graphics
This chapter provides a brief overview of working with 3D graphics content.
9.1JSR 184 Overview
JSR 184 is a specification that defines the Mobile 3D Graphics (M3G) API for J2ME. This API provides 3D functionality in a compact package that’s appropriate for CLDC/MIDP devices. The API provides two methods for displaying 3D graphics content. The immediate mode API makes it possible for applications to directly create and manipulate 3D elements. Layered on top of this is a scene graph API, also called retained mode, that makes it possible to load and display entire 3D scenes that have been designed ahead of time. Applications are free to use whichever approach is most appropriate or to use a combination of the retained mode and immediate mode APIs. The JSR 184 specification also defines a file format (.m3g) for scene graphs.
For more information, consult the JSR 184 specification:
http://jcp.org/en/jsr/detail?id=184
JSR 184 provides a standard API for CLDC/MIDP devices, enabling a new generation of 3D applications. The immediate mode API, in turn, is compatible with OpenGL ES, a standard lightweight API for 3D graphics. See http:// khronos.org/ for more information on OpenGL ES.
9.2Immediate Mode
Immediate mode is appropriate for applications that generate 3D graphics content algorithmically, like scientific visualizations or statistical graphs. The application creates 3D objects and manipulates them directly.
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