If doxysphinx doesn't fit your needs maybe there are some other open source tools which might be a better fit:
These seem abandoned:
The tools Breathe and Exhale needs special mention, as doxysphinx was invented in a large C++ project (> 11,000 C++ files) where we started out with these two tools. With the large project size, Exhale did not perform too well and Breathe did not quite support all C++ and Doxygen features that C++ developers expected. Doxysphinx was invented to overcome these limitations.
Breathe is useful for smaller C++ projects when parts of C++ Doxygen documentation needs to be integrated into the Sphinx documentation using Breathe directives. When the complete C++ Doxygen documentation needs to be integrated into Sphinx, the following options are available:
Doxysphinx outperforms the two options w.r.t to speed and features, as it simply reuses Doxygen output.
Also note that Breathe and Doxysphinx can co-exist in the same project.