1991-2006
Silicon Graphics, Inc.
glXCreateNewContext
3G

# glXCreateNewContext

create a new GLX rendering context

## C Specification

                    GLXContext glXCreateNewContext
                    Display * dpy
                    GLXFBConfig config
                    int render_type
                    GLXContext share_list
                    Bool direct

## Parameters

`dpy`

  Specifies the connection to the X server.

`config`

  Specifies the GLXFBConfig structure with the desired attributes for the context.

`render_type`

  Specifies the type of the context to be created. Must be one of `GLX_RGBA_TYPE` or `GLX_COLOR_INDEX_TYPE`.

`share_list`

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

`share_list`

  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

`glXCreateNewContext` creates a GLX rendering context and returns its handle. This context can be used to render into GLX windows, pixmaps, or pixel buffers. If `glXCreateNewContext` fails to create a rendering context, `NULL` is returned.

If `render_type` is `GLX_RGBA_TYPE`, then a context that supports RGBA rendering is created. If `config` is `GLX_COLOR_INDEX_TYPE`, then context supporting color-index rendering is created.

If `render_type` is not `NULL`, then all display-list indexes and definitions are shared by context `render_type` 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 `share_list` 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 `share_list` is `True`.) If `share_list` 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.

## Notes

`glXCreateNewContext` is available only if the GLX version is 1.3 or greater.

If the GLX version is 1.1 or 1.0, the GL version must be 1.0. If the GLX version is 1.2, then the GL version must be 1.1. If the GLX version is 1.3, then the GL version must be 1.2.

## Errors

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

`GLXBadContext` is generated if `render_type` is not a GLX context and is not `NULL`.

`GLXBadFBConfig` is generated if `config` is not a valid GLXFBConfig.

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

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

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

## See Also

glXChooseFBConfig, glXCreateContext, glXDestroyContext, glXGetFBConfigs, glXGetFBConfigAttrib, glXIsDirect, glXMakeContextCurrent

## Copyright

Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.