This sample demonstrates how to use OpenGL ES 3.0 from JNI/native code.

The sample can be built two different ways:
  * Compatible with API level 11 and later [*1]
  * Require API level 18 or later.
Both versions include an OpenGL ES 2.0 fallback path for devices that don't
support OpenGL ES 3.0.

To build and install the sample:
$ ln -s AndroidManifest-$N.xml AndroidManifest.xml
$ ln -s Android-$N.mk jni/Android.mk
$ $ANDROID_SDK/tools/android update project --path . --target android-$N
$ ../../ndk-build
$ ant debug
$ adb install bin/GLES3JNIActivity-debug.apk
where $N is '11' or '18' and
ANDROID_SDK is the root of your SDK installation.

The OpenGL ES 3.0 rendering path uses a few new features compared to the
OpenGL ES 2.0 path:

* Instanced rendering and vertex attribute divisor to reduce the number of
  draw calls and uniform changes.
* Vertex array objects to reduce the number of calls required to set up
  vertex attribute state on each frame.
* Explicit assignment of attribute locations, eliminating the need to query
  assignments.


[*1] The only dependency on API level 11 is the call to
     setEGLContextClientVersion in GLES3JNIView. With a custom
     EGLConfigChooser and EGLContextFactory the sample would be compatible
     with older API levels.