1991-2006
Silicon Graphics, Inc.
glXCopyContext
3G
glXCopyContext
copy state from one rendering context to another
C Specification
void glXCopyContext
Display * dpy
GLXContext src
GLXContext dst
unsigned long mask
Parameters
dpy
Specifies the connection to the X server.
src
Specifies the source context.
dst
Specifies the destination context.
mask
Specifies which portions of src state are to be copied to dst.
Description
glXCopyContext copies selected groups of state variables from src to dst.
mask indicates which groups of state variables are to be copied.
mask contains the bitwise OR of the same symbolic names that are
passed to the GL command glPushAttrib.
The single symbolic constant GLX_ALL_ATTRIB_BITS can be used to
copy the maximum possible portion of rendering state.
The copy can be done only if the renderers named by src and dst
share an 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.
Not all values for GL state can be copied.
For example,
pixel pack and unpack state,
render mode state,
and select and feedback state are not copied.
The state that can be copied is exactly the state that is manipulated
by the GL command
glPushAttrib.
An implicit glFlush is done by glXCopyContext if src is the current
context for the calling thread.
Notes
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
BadMatch is generated if rendering contexts src and dst
do not share an address space
or were not created with respect to the same screen.
BadAccess is generated if dst is current to any thread
(including the calling thread) at the time glXCopyContext is called.
GLXBadCurrentWindow is generated if src is the current
context and the current drawable is a window that is no longer valid.
GLXBadContext is generated if either src or dst is not
a valid GLX context.
See Also
glPushAttrib,
glXCreateContext,
glXIsDirect
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/.