Build a plugin

This page presents how to build an external plugin, i.e. a plugin which is not provided in the source code of SOFA.

⚠️ WARNING: In most cases, the version of a plugin follows the version of SOFA. For compatibility reasons, it is preferable to compile the version of the plugin corresponding to your SOFA version. For example, if you have the SOFA v23.06 binaries, you will need to compile plugins using their v23.06 version (i.e. their v23.06 branch).

Two ways of building a plugin are possible:

• you are compiling SOFA and you integrate your plugin project along SOFA (aka in-tree build).
• you have an install of SOFA (either you downloaded a pre-built configuration, or you installed by yourself from a SOFA build), and you want to use this installation to build your plugin (aka out-of-tree build)

In-tree build

Preferred file architecture

If you use the source code of SOFA, you want compile and use one or more external plugins it is preferred to create one specific repository outside SOFA where you can checkout all these external plugins. This structure is preferred since it will allow a clean organization of external plugins in one single repository. Let’s note the path to this repository /ext_plugin_repo/.

In this directory, the structure is:

• ext_plugin_repo/
  • plugin1/
  • plugin2/
  • …

CMakeList of the repository

In order to handle this repository as one single set of external plugins, you need to write a short CMakeList.txt file as follows:

cmake_minimum_required(VERSION 2.8.12)

find_package(SofaFramework)

sofa_add_subdirectory(plugin path_to_plugin1/  name_of_project_plugin1)
sofa_add_subdirectory(plugin path_to_plugin2/  name_of_project_plugin2)

CMake option in SOFA

To compile all the external plugins located in this repository, all you need to do is to set the path to this repository (/ext_plugin_repo/) in the CMake variable: SOFA_EXTERNAL_DIRECTORIES.

This will directly configure and allow to compile all specified plugins from SOFA.

Out-of-tree build

Your plugin will be considered as a standalone project, and SOFA will be simply a dependency for your CMake project.

CMake configuration

The main CMakeFile.txt of the plugin will not be different from the in-tree way.

Afterwards, in CMake (cmake, ccmake, cmake-gui), you just set the source to the root of your plugin, as any project based on CMake.

The only mandatory requirement for your project to find SOFA is to edit the CMake variable CMAKE_PREFIX_PATH and set the value to the path of the lib/cmake directory of your SOFA installation:

After setting the eventual third-party libraries (Qt, Eigen, etc), you will be able to build your plugin.

Finally, you are advised to install directly your plugin into the SOFA installation, essentially to load it more easily with runSofa. This is possible by setting the CMake variable CMAKE_INSTALL_PREFIX in your plugin configuration.