Now WIDL is good enough to generate a drop-in replacement for Wine's wtypes.h (attached) from a suitably crafted Wine-compatible wtypes.idl (also attached). I've included all the definitions that were already in Wine's wtypes.h (but I was too lazy to do everything that's in Microsoft's wtypes.idl yet).
What do you think, is this good enough to go into Wine? Are there some desirable changes to widl or wtypes.idl? And should IDL files go into the main include dir along with the other Win32 headers?
IDL-generated files would also eventually obsolete all the current wine/obj_*.h files, but those obj_* files seem to be somewhat more logically structured than MS's own IDL files, should we craft Wine's IDL files accordingly, and maybe have some top-level .idl files in include/ and some sub-.idl files under include/wine/, like it's done now in e.g. objidl.h?
Note that I will work on ReWind, not directly on Wine, so I probably won't be able to submit massive "change all files to include this instead of that" patches (that apply to Wine) with any new files.