h5. ivp-extend

We start in the ivp-extend directory of the hovergroup svn.  The svn can be viewed or checked out by anyone at [https://code.google.com/p/hovergroup/].

{code}
↓hovergroup
  ↓ivp-extend
    →base
    →josh
    →missions
    →trunk
{code}

The {{missions}} directory contains all of the configuration files used to run a MOOS mission on the vehicles.  For more information check out [hovergroup:Mission File Organization].  Ignore the {{project_files}} directories and any files located immediately in the {{ivp-extend}} directory.

The remaining directories are all for source code. {{trunk}} contains the majority of the hovergroup applications and libraries.  Individuals also have their own directories for programs that are specific to their experiments.  The {{base}} directory can be copied and renamed to create new individual directories.

h5. ivp-extend \-> base

Let's look at the basic structure of one of these directories.

{code}
↓hovergroup
  ↓ivp-extend
    ↓base
      →bin
      →build
      →data
      →docs
      →lib
      →missions
      →scripts
      →src
       build_proto.sh
       CMakeLists.txt
{code}

Here's what you should know:

{{bin}} \- Where built executables are placed.

{{data}} \- If you need to associate some sort of data file with your program that doesn't depend on the mission, this might be the place for it.

{{docs}} \- For documentation, though usually the wiki is preferred.

{{lib}} \- Where built libraries are placed.

{{missions}} \- You can use this directory for testing mission files, but actual missions should use the {{ivp-extend/missions}} directory.

{{scripts}} \- For command line scripts, which we'll come back to.

{{src}} \- The source code itself.

{{build_proto.sh}} and {{CMakeLists.txt}} are both part of the build process, which we'll also come back to.

Within the {{src}} directory you'll see that each library or application has its own folder, and within those folder are header and source files.  Folders for libraries are prefixed with {{lib\_}}.  Almost every folder also contains a {{CMakeLists.txt}}.

h5. Building

Let's switch to {{ivp-extend/trunk}} now to look at how the code gets built. {{make}} is responsible for building the c+\+ source code into an executable, but it needs a {{Makefile}} to tell it what to do.  We use {{cmake}} to create these {{Makefiles}}.

Cmake is run in the top directory ({{ivp-extend/trunk}}) using the command {highlight:#a0a0a0}{{cmake .}}{highlight} or {#a0a0a0}{{ccmake .}}{highlight} if you need a user interface.  It drills down through the source tree looking at every {{CMakeLists.txt}} file on the way.