OpenGL man pages
glXMakeCurrent - attach a GLX context to a window or a GLX pixmap
Bool glXMakeCurrent( Display *dpy,
GLXContext ctx )
dpy Specifies the connection to the X server.
drawable Specifies a GLX drawable. Must be either an X window ID or a GLX
ctx Specifies a GLX rendering context that is to be attached to
glXMakeCurrent does two things: It makes ctx the current GLX rendering
context of the calling thread, replacing the previously current context if
there was one, and it attaches ctx to a GLX drawable, either a window or a
GLX pixmap. As a result of these two actions, subsequent OpenGL rendering
calls use rendering context ctx to modify GLX drawable drawable. Because
glXMakeCurrent always replaces the current rendering context with ctx,
there can be only one current context per thread.
Pending commands to the previous context, if any, are flushed before it is
The first time ctx is made current to any thread, its viewport is set to
the full size of drawable. Subsequent calls by any thread to
glXMakeCurrent with ctx have no effect on its viewport.
To release the current context without assigning a new one, call
glXMakeCurrent with drawable and ctx set to None and NULL respectively.
glXMakeCurrent returns True if it is successful, False otherwise. If False
is returned, the previously current rendering context and drawable (if any)
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 subprocess group is
equivalent to a process.
BadMatch is generated if drawable was not created with the same X screen
and visual as ctx. It is also generated if drawable is None and ctx is not
BadAccess is generated if ctx was current to another thread at the time
glXMakeCurrent was called.
GLXBadDrawable is generated if drawable is not a valid GLX drawable.
GLXBadContext is generated if ctx is not a valid GLX context.
GLXBadContextState is generated if glXMakeCurrent is called between a
glBegin and the corresponding call to glEnd.
GLXBadContextState is also generated if the rendering context current to
the calling thread has OpenGL renderer state GL_FEEDBACK or GL_SELECT.
GLXBadCurrentWindow is generated if there are pending OpenGL commands for
the previous context and the current drawable is a window that is no longer
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.
Fri Dec 6 11:18:03 EST 1996
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