I’m a member of the JEDI project (Joint Endeavour of Delphi Innovators). The original goal of the project was to provide Pascal conversions of C/C++ header files, and objects based on these conversions, as well as documentation and help files. Also components to aid in the use of the conversions, were planned.
In the mean time, JEDI has become the home of many Open Source projects for Delphi, and it is still growing. The best known projects are probably the JCL (JEDI Code Library) and JVCL (JEDI Visual Component Library).
You can find some conversions I have made, either on the JEDI site, or on my download page.