I'm just wondering how TeX labels in metapost pictures are generated when using mplib: if the set of pictures are all build through the library which saves loading time and hd read/writes, it would be strange to launch another TeX compiler.
i'm not sure what you mean .. in mkiv there are no tex compilers launched, everything happens internally
In the case of a standalone metapost graphic, if some label requires TeX typesetting, the metapost file is first processed by mpost, then the need for TeX typesetting is discovered and TeX is launched to produce the labels and they are incorporated back into the metapost figure, right? So in the case of mplib who takes care of the label typesetting? Does your already running instance of TeX (LuaTeX and mkiv) handles the job of typesetting the labels? Even if this is completely disconnected from the flow of the document currently processed? Olivier