glXCreateContextWithConfigSGIX(3G) OpenGL Reference - GLX
NAMEglXCreateContextWithConfigSGIX - create a new GLX rendering context with
specified frame buffer configuration
C SPECIFICATION
GLXContext glXCreateContextWithConfigSGIX( Display *dpy,
GLXFBConfigSGIX config,
int render_type,
GLXContext share_list,
Bool direct )
PARAMETERS
dpy Specifies the connection to the X server.
config Specifies the GLX frame buffer configuration that defines
the frame buffer resources available to the rendering
context.
render_type Specifies the type of rendering context desired. Must be one
of GLX_RGBA_TYPE_SGIX or GLX_COLOR_INDEX_TYPE_SGIX.
share_list Specifies the context with which to share display lists and
texture objects. 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).
DESCRIPTIONglXCreateContextWithConfigSGIX creates a GLX rendering context and
returns its handle. If glXCreateContextWithConfigSGIX 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 and the connection is to an X
server that is local. If direct is False, then a rendering context that
renders through the X server is always created. Direct rendering
provides a performance advantage. However, direct rendering contexts
cannot be shared outside a single process, and they cannot be used to
render to GLX pixmaps.
If share_list is not NULL, then all display-list and texture object
indexes and definitions are shared by context share_list and by the newly
created context. An arbitrary number of contexts can share a single
Page 1
glXCreateContextWithConfigSGIX(3G) OpenGL Reference - GLX
display-list and texture object space, as long as these contexts 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.
The context created by glXCreateContextWithConfigSGIX can be used to
render into windows, GLX pixmaps and/or GLX pbuffers. Before rendering,
the context must be made current to a thread and GLX drawable by calling
glXMakeCurrent. The context can only be made current to a drawable that
is compatible with it. This requires the following conditions to be met:
The context's render_type attribute (either GLX_RGBA_TYPE_SGIX or
GLX_COLOR_INDEX_TYPE_SGIX) is supported by the GLXFBConfigSGIX that
the drawable was created with. For example, if the context's
render_type attribute is GLX_RGBA_TYPE_SGIX, then the
GLX_RENDER_TYPE_SGIX attribute of the drawable's GLXFBConfigSGIX
must have the GLX_RGBA_BIT_SGIX bit set.
All color buffers and ancillary buffers that exist in both the
drawable's and context's GLXFBConfigSGIX have the same depth. For
example, a GLXFBConfigSGIX that has a front left buffer and a back
left buffer with red, green and blue sizes of 4 is not compatible
with a GLXFBConfigSGIX that has only a front left buffer with red,
green and blue sizes of 8. However, it is compatible with a
GLXFBConfigSGIX that has only a front left buffer if the red, green
and blue sizes are 4.
NOTESglXCreateContextWithConfigSGIX is part of the GLX_SGIX_fbconfig
extension.
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.
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 share_list.
GLXBadFBConfigSGIX is generated if config is not a valid GLXFBConfig.
Page 2
glXCreateContextWithConfigSGIX(3G) OpenGL Reference - GLX
GLXBadContext is generated if share_list 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.
BadValue if render_type does not refer to a valid rendering type.
SEE ALSO
glXDestroyContext, glXIsDirect, glXCreateContext, glXMakeCurrent,
glXGetFBConfigAttribSGIX, glXChooseFBConfigSGIX
Page 3
