C SPECIFICATION

       Bool glXMakeCurrent( Display *dpy,
                            GLXDrawable drawabl )

PARAMETERS

       dpy      Specifies the connection to the X server.

       drawabl  Specifies  a GLX drawable.  Must be either an X window ID or a
                GLX pixmap ID.

       _param3  Specifies a GLX rendering context that is to  be  attached  to
                drawabl.

DESCRIPTION

       glXMakeCurrent  does  two things: It makes _param3 the current GLX ren-
       dering context of the calling thread, replacing the previously  current
       context  if  there  was one, and it attaches _param3 to a GLX drawable,
       either a window or a GLX pixmap.  As a result  of  these  two  actions,
       subsequent  GL  rendering calls use rendering context _param3 to modify
       GLX drawable drawabl (for reading and writing).  Because glXMakeCurrent
       always  replaces  the current rendering context with _param3, there can
       be only one current context per thread.

       Pending commands to the previous context, if any, are flushed before it
       is released.

       The  first  time _param3 is made current to any thread, its viewport is
       set to the full size of drawabl.  Subsequent calls  by  any  thread  to
       glXMakeCurrent with _param3 have no effect on its viewport.

       To  release  the  current  context  without  assigning  a new one, call
       glXMakeCurrent with drawabl set None and _param3 set to NULL

       glXMakeCurrent returns True if it is successful, False  otherwise.   If
       False  is  returned, the previously current rendering context and draw-
       able (if any) remain unchanged.

NOTES

       A process is a single-execution environment, implemented  in  a  single
       address space, consisting of one or more threads.

       A  thread  is  one of a set of subprocesses that share a single address
       space, but maintain separate program counters, stack spaces, and  other
       related  global  data.  A thread that is the only member of its subpro-
       cess group is equivalent to a process.

ERRORS

       BadMatch is generated if drawabl was not created with the same X screen
       and  visual  as  _param3.   It is also generated if drawabl is None and
       _param3 is not NULL.
       GLXBadCurrentWindow  is  generated if there are pending GL commands for
       the previous context and the current drawable is a window  that  is  no
       longer valid.

       BadAlloc  may  be  generated  if  the  server has delayed allocation of
       ancillary buffers until glXMakeCurrent is called, only to find that  it
       has insufficient resources to complete the allocation.

SEE ALSO

       glXCreateContext,        glXCreateGLXPixmap       glXGetCurrentContext,
       glXGetCurrentDisplay, glXGetCurrentDrawable, glXGetCurrentReadDrawable,
       glXMakeContextCurrent



                                                            GLXMAKECURRENT(3G)