Source documentation

The FreeCAD source code is commented to allow automatic programming documentation generation using Doxygen, a popular source code documentation system. Doxygen can document both the C++ and Python parts of FreeCAD, resulting in HTML pages with hyperlinks to each documented function and class.

The documentation is hosted online at the FreeCAD API website. Please note that this documentation may not always be up to date; if you need more details, download FreeCAD's latest source code and compile the documentation yourself. If you have pressing questions about the code please ask in the developer section of the FreeCAD forum.

Compiling the API documentation follows the same general steps as compiling the FreeCAD executable, as indicated in the compile on Unix page.



Build source documentation
If you have Doxygen installed, it is very easy to build the documentation. Also install Graphviz to be able to produce diagrams showing the relationships between different classes and libraries in the FreeCAD code. Graphviz is also used by FreeCAD's dependency graph to show the relationships between different objects.

Then follow the same steps you would do to compile FreeCAD, as described on the compile on Unix page, and summarized here for convenience.
 * Get the source code of FreeCAD and place it in its own directory.
 * Create another directory in which you will compile FreeCAD and its documentation.
 * Configure the sources with, making sure you indicate the source directory, and specify the required options for your build.
 * Trigger the creation of the documentation using.

While you are inside the build directory issue the following instruction to create only the documentation.

As mentioned in compiling (speeding up), the option sets the number of CPU cores used for compilation. The resulting documentation files will appear in the directory

The point of entrance to the documentation is the file, which you can open with a web browser:

The target will generate a significant amount of data, around 5 GB of new files, particularly due to the diagrams created by Graphviz.

An alternative, smaller version of the documentation which takes only around 600 MB can be generated with a different target. This is the version displayed on the FreeCAD API website.

Other versions
FreeCAD 0.12 documentation hosted in Sourceforge.

FreeCAD 0.16 development documentation built by qingfeng.xia.

FreeCAD 0.19 development documentation built by qingfeng.xia.

Integrate Coin3D documentation
On Unix systems it is possible to link Coin3D source documentation with FreeCAD's. This allows for easier navigation and complete inheritance diagrams for Coin derived classes.


 * Install the, , or similarly named package.
 * Unpack the archive located in ; the files may be already unpacked in your system.
 * Generate again the source documentation.

If you don't install the documentation package for Coin, the links will be generated to access the online documentation at BitBucket. This will happen if a Doxygen tag file can be downloaded at configure time with.

Using Doxygen
See the Doxygen page for an extensive explanation on how to comment C++ and Python source code so that it can be processed by Doxygen to automatically create the documentation.

Essentially, a comment block, starting with or  for C++, or  for Python, needs to appear before every class or function definition, so that it is picked up by Doxygen. Many special commands, which start with or, can be used to define parts of the code and format the output. Markdown syntax is also understood within the comment block, which makes it convenient to emphasize certain parts of the documentation.