How to load math.c?

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I am successfully compiling the code and am having great success with the 
tutorials, thanks for keeping this updated.

I am moving on to the newer tutorials however, that include the math.c file and 
I am having difficulty loading this file into my eclipse project.  I am finding 
a few pages online, but they are definitely beyond my current scope of 
experience, and I have a feeling they are overcomplicating the problem.

I am using Mac OSX and an Eclipse environment, testing and debugging on a 
TMobile G1 using the 1.5/1.6 SDK.  Thank you so much and keep up the good work!

Original issue reported on code.google.com by kevingra...@gmail.com on 30 Jun 2010 at 7:17

[GoogleCodeExporter]

SOLVED
Short Answer: You need to use the Android Native Development Kit (NDK) to 
compile a native shared library, which will be included in the Android 
Application Package.

Long Answer:
1) Download and install the NDK (you will also need Cygwin if using Windows).

2) I suggest you compile, build, deploy and run at lest the hello-jni sample to 
test the install and learn the tools.

2a) Optional, if using Eclipse, install the XML and C/C++ plug-ins (Web Tools 
and CDT) if you plan on using the NDK to develop native code.

3) Basicly, follow the instructions in part "III. NDK development in practice" 
from OVERVIEW.TXT in the NDK docs:
3a) Make JNI directory under /OpenGLdemos
3b) Copy math.c to the JNI directory.
3c) Copy Android.mk from the <NDK>/samples/hello-jni/jni
3d) Edit Android.mk as follows:
      LOCAL_MODULE    := opengl-math
      LOCAL_SRC_FILES := math.c

4) Compile and Build the same way you did for hello-jni

Additional Notes:
If Eclipse gives you "Build Path" errors, go to "OpenGLdemos->properties->Java 
Build Path->Order and Export".  Make sure "Android 1.5" is UN-CHECKED and 
listed LAST.  Why? I have no idea, but it fixed it.

In your java file(s) You must explicitly load the shared library and prototype 
the library routines using the 'native' keyword.  See common/GlMatrix.java

The library created is actually named lib<LOCAL_MODULE>.so, but the package 
manager deals with it for you. 

By default, native code is compiled using 16-bit "thumb" instructions.  Set the 
"Module-description variable"
  LOCAL_ARM_MODE := arm
in Android.mk to force the compiler to use 32-bit "arm" instructions.  I saw a 
noticeable performance gain on my MOTO Droid! (See the file ANDROID-MK.TXT for 
details) 

Development Tools:
Eclipse 3.5.2
Android SDK r6
ADT 0.9.7
USB Drivers r3
NDK r4 (+Cygwin)

Cheers!
-RWZ

Original comment by robert.z...@gmail.com on 6 Jul 2010 at 7:29