title: How to use android-ndk?
body: <p>I use PTAM code taken from <a href="https://github.com/BeLioN-github/PTAM" rel="nofollow">here</a>. I try to make an android application with this code.</p>
  
  <p>The PTAM code uses libcvd, TooN, gvars3 library. I generate a .so file from my c++ test file using <code>ndk-build</code>.</p>
  
  <p>Firstly, I try to run below code on android phone : </p>
  
  <pre><code>#include &lt;string.h&gt;
  #include &lt;jni.h&gt;
  
  extern "C" {
  
      int returnInt()
      {
  
          int returnVal = 4;
          return returnVal;
      }
  }
  </code></pre>
  
  <p>It can generate .so file without any errors. If I add     <code>#include &lt; TooN/TooN.h &gt;</code> , `ndk-build says that  </p>
  
  <pre><code>fatal error: TooN/TooN.h: No such file or directory
   #include &lt;TooN/TooN.h&gt;
                         ^
  compilation terminated.
  </code></pre>
  
  <p>Android.mk is :</p>
  
  <pre><code>LOCAL_PATH := $(call my-dir)
  
  include $(CLEAR_VARS)
  
  LOCAL_MODULE    := test-jni
  LOCAL_SRC_FILES := test-jni.cpp
  
  include $(BUILD_SHARED_LIBRARY)
  </code></pre>
  
  <p>How can I solve this error message?</p>