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glXCreateContext()
NAME
  glXCreateContext - create a new GLX rendering context

SYNOPSIS
  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(3), glXGetConfig(3), glXIsDirect(3), glXMakeCurrent(3)

Index for Section 3

Alphabetical listing for G

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