To generate HTML documentation from sources contained in dox subdirectory, you need to have Doxygen 1.8.4 (or above) installed on your system. Tcl/Tk is required when configuring a full OCCT build with DRAW enabled.
OCCT documentation is generated via CMake targets. Enable -DBUILD_DOC_Overview=ON
when configuring the build, then build the desired target:
To generate Overview documentation:
cmake --build . --target Overview
To generate Reference manual:
cmake --build . --target RefMan
To generate all documentation:
cmake --build . --target doc
See @ref occt_contribution__documentation for prerequisites and details on OCCT documentation system.