On Thursday 08 March 2007 6:20 pm, Matt Newell wrote: > On Thursday 08 March 2007 01:11, Phil Thompson wrote: > > On Thursday 08 March 2007 8:40 am, Matt Newell wrote: > > > On Thursday 08 March 2007 00:07, Ulrich Berning wrote: > > > > [EMAIL PROTECTED] wrote: > > > > >Eh, I have just realized that I have replied directly to Phil > > > > > Thompson, not to this list (this is because I have used unfamiliar > > > > > webmail client). So this is our conversation: > > > > > > > > > >*** Me: *** > > > > >You can look at that example by Zack Rusin, it is very simple, here > > > > > is code: http://ktown.kde.org/~zrusin/examples/argb.tar.bz2 (look > > > > > at main.cpp) > > > > > > > > > >That Display instance come directly from xlib, it is created by > > > > > XOpenDisplay: http://lxr.freedesktop.org/ident?i=XOpenDisplay > > > > > > > > > >In Python, I am using ctypes module to directly access xlib (libX11) > > > > >and call XOpenDisplay. > > > > > > > > > >*** Phil: *** > > > > >I meant, in the context of PyQt. PyQt needs to know about the type. > > > > > > > > > >*** Me: *** > > > > >I can't help you much in this, I don't know much about ctypes, I > > > > > have only learned it because I want to create ARGB windows with > > > > > PyQt (and then I realized that I can't do it because PyQt doesn't > > > > > support it). But you can try this code: > > > > > > > > > >### Python code ### > > > > >import ctypes > > > > > > > > > >class Display(ctypes.Structure): > > > > >pass > > > > > > > > > >xlib = ctypes.CDLL('libX11.so.6') > > > > >xlib.XOpenDisplay.restype = ctypes.POINTER(Display) > > > > >xlib.XOpenDisplay.argtypes = [ctypes.c_char_p] > > > > > > > > > >display = xlib.XOpenDisplay(':0.0') > > > > >### End of Python code ### > > > > > > > > > >This will create 'display' object, which is pointer to 'Display' > > > > > structure (which is derived from standard ctypes.Structure). > > > > > > > > > >But this is all I can tell you, as I said I don't know any details > > > > > about this process, only that it works (I have tried creating > > > > > window with pure xlib). > > > > > > > > > >Ctypes are standard module in python 2.5 (for Python 2.4 it is > > > > > external module), so I think PyQt should support it. > > > > > > > > The ctypes extension doesn't build on AIX, HP-UX, IRIX and Solaris. > > > > With some changes, it may build on IRIX and Solaris, because libffi > > > > has been ported to these platforms. On AIX and HP-UX, you have > > > > definitely lost. I've never understood, why ctypes became a standard > > > > module. > > > > > > > > PyQt works on the above platforms. Making it dependent on the ctypes > > > > extension seems to be a bad idea. > > > > > > Display is just a pointer. I think PyQt could support accepting a > > > ctypes pointer as an arguement without depending on ctypes being > > > available. The ctypes pointer is simply passed as a PyObject * and > > > regular python api calls are used to check that it is indeed a ctypes > > > pointer, and to get the value. > > > > Ironically ctypes doesn't provide the necessary C API to do this. However > > if (in Python) you can get the address of the real data structure as a > > number (ctypes.addressof() ?) then you can create a sip.voidptr from it > > and I can add the ctors to accept that. > > import ctypes > import sip > > class Display(ctypes.Structure): > pass > > xlib = ctypes.CDLL('libX11.so.6') > xlib.XOpenDisplay.restype = ctypes.POINTER(Display) > xlib.XOpenDisplay.argtypes = [ctypes.c_char_p] > > display = xlib.XOpenDisplay(':0.0') > > dvp = ctypes.cast(display,ctypes.c_void_p) > print dvp.value > svp = sip.voidptr(dvp.value) > print int(svp) > > > I think the same thing could also be accomplished entirely in c++, not sure > if it would be worth it.
The attached should work with current snapshots (SIP and PyQt4). I don't know if all the ctypes magic is needed. Phil
ct.py
Description: application/python
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