3D compass is a sample Android application showing how to use a
SurfaceView to display a dynamically-updated 3D arrow with OpenGL that
takes its direction from the orientation sensor, composited on top of
a live camera preview image. The source code includes the following
utility classes:
  * CameraUseful: some routines for managing the camera and decoding
    image data
  * EGLUseful: management of EGL context and doing offscreen OpenGL
    rendering using pbuffers
  * GeomBuilder: basic management of 3D object geometry and rendering
  * Lathe: uses GeomBuilder to construct objects with rotational symmetry
  * Compass: how to use the orientation sensor data to draw a 3D
    compass arrow

Note that the compass direction is sometimes inaccurate--at least, on
my HTC Desire it is. However, turning the phone this way and that will
often nudge it back into a sensible reading.

Contents:
    src/ -- Java sources for the Android app
    res/ -- resources for the Android app
    AndroidManifest.xml, build.xml, *.properties -- for driving
        Google's Android build tools (note that you will have to
        provide a couple more of these--see INSTALL for details)
    README -- this file
    INSTALL -- build/installation instructions
    LICENSE -- licence (Apache 2.0, same as Google's sample code)

Lawrence D'Oliveiro <ldo@geek-central.gen.nz>