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GLXCREATECONTEXT()                                          GLXCREATECONTEXT()

NAME
       glXCreateContext - create a new GLX rendering context

C SPECIFICATION
       GLXContext glXCreateContext( Display *dpy,
                                    XVisualInfo *vis,
                                    GLXContext shareList,
                                    Bool direct )

PARAMETERS
       dpy        Specifies the connection to the X server.

       vis        Specifies the visual that defines the frame buffer resources
                  available to the rendering context.  It is a pointer to an
                  XVisualInfo structure, not a visual ID or a pointer to a
                  Visual.

       shareList  Specifies the context with which to share display lists.
                  NULL indicates that no sharing is to take place.

       direct     Specifies whether rendering is to be done with a direct
                  connection to the graphics system if possible (True) or
                  through the X server (False).

DESCRIPTION
       glXCreateContext creates a GLX rendering context and returns its
       handle.  This context can be used to render into both windows and GLX
       pixmaps.  If glXCreateContext fails to create a rendering context, NULL
       is returned.

       If direct is True, then a direct rendering context is created if the
       implementation supports direct rendering, if the connection is to an X
       server that is local, and if a direct rendering context is available.
       (An implementation may return an indirect context when direct is True).
       If direct is False, then a rendering context that renders through the X
       server is always created.  Direct rendering provides a performance
       advantage in some implementations.  However, direct rendering contexts
       cannot be shared outside a single process, and they may be unable to
       render to GLX pixmaps.

       If shareList is not NULL, then all display-list indexes and definitions
       are shared by context shareList and by the newly created context.  An
       arbitrary number of contexts can share a single display-list space.
       However, all rendering contexts that share a single display-list space
       must themselves exist in the same address space.  Two rendering
       contexts share an address space if both are nondirect using the same
       server, or if both are direct and owned by a single process.  Note that
       in the nondirect case, it is not necessary for the calling threads to
       share an address space, only for their related rendering contexts to
       share an address space.

       If the GL version is 1.1 or greater, then all texture objects except
       object 0, are shared by any contexts that share display lists.

NOTES
       XVisualInfo is defined in Xutil.h. It is a structure that includes
       visual, visualID, screen, and depth elements.

       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.

       It may not be possible to render to a GLX pixmap with a direct
       rendering context.

ERRORS
       NULL is returned if execution fails on the client side.

       BadMatch is generated if the context to be created would not share the
       address space or the screen of the context specified by shareList.

       BadValue is generated if vis is not a valid visual (for example, if a
       particular GLX implementation does not support it).

       GLXBadContext is generated if shareList is not a GLX context and is not
       NULL.

       BadAlloc is generated if the server does not have enough resources to
       allocate the new context.

SEE ALSO
       glXDestroyContext, glXGetConfig, glXIsDirect, glXMakeCurrent

                                                            GLXCREATECONTEXT()