Sample Android app giving 3D display of GPS satellite directions
Java C++ C Makefile
Latest commit 6c678c7 Jul 19, 2016 Lawrence D'Oliveiro fix signing with OpenJDK 8


GPS Sat Pointer is a sample Android application demonstrating how to
use OpenGL-ES 2.0 to display a dynamically-updated set of 3D arrows
showing the position of GPS satellites and the current compass orientation.

The source code includes the following utility classes:
  * GeomBuilder: basic management of 3D object geometry and rendering
  * GLUseful: useful OpenGL-related stuff, including error-checking
    and management of shader programs
  * GLView: takes an image rendered via a Canvas to an offscreen
    Bitmap and displays it as a texture on a planar rectangle in
  * Lathe: uses GeomBuilder to construct objects with rotational symmetry
  * Mat4f: functional operations on matrices representing 3D
    homogeneous coordinates
  * PaintBuilder: convenient construction of Paint objects by chaining
    setup calls
  * Vec3f: functional operations on vectors representing 3D coordinates

Note that the compass direction is often inaccurate to begin with.
However, turning the phone this way and that will often nudge it
back into a sensible reading.

    art/ -- artwork for icon
    src/ -- Java sources for the Android app
    res/ -- resources for the Android app
    jni/ -- C sources 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 <>