The libsmartfactory is a free and open source software solution which provides several easy to use interfaces for
Smart Factory/Industry 4.0 applications:
The sources of libsmartfactory are available in public GIT at https://sourceforge.net/p/oapc/code/ci/master/tree/libsmartfactory/ in a variant for wxWidgets (using wxString and wxXML) and in a variant which uses std::string and PugiXML.
The libsmartfactory API is described in detail in manual from https://sourceforge.net/p/oapc/code/ci/master/tree/sdk_manual.pdf in section "Shared library libsmartfactory".
For the Smart Interface there is also an Android-App available which can be used to visualise machine states announced by a device or machine which uses the libsmartfactory:
More information including downloads and full sources are available at the Sourceforge™ project page at https://sourceforge.net/projects/oapc/