is there a way to convert pd patches to rough C or C++ language lines?
not at this time.
but you have the source code of pure data... If you're brave...
Last autumn I did start work on a Pd patch to Pd external converter (written in Java), but didn't get very far. I started writing this pd2external compiler because I wrote a synthesizing patch that worked in control-time (necessary because I needed to sync the oscillators) and it became too complex for my 1.4GHz Athlon to run in realtime (gave great results with writesf~ though). It wouldn't ever have generated pretty C code, like expressions and such, but the code would be able to be optimised to machine code quite well by a C compiler.
As far as I can remember, given a Pd patch restricted to some simple objects ([trigger], [+], [float], [inlet], [outlet], [loadbang]), it would print out whether the variables at the inlets of each object were local variables (used only by each path of execution) or state variables (can be read by a different path of execution from the one that writes to it).
http://puredata.info/Members/claudiusmaximus is where you'll find what little progress I made.
Anyone could tell me how can I use in PD an object working as SEQ in Max?