glXCopyContext: copy state from one rendering context to another.
C Specification |
unsigned long mask)
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 GL_ALL_ATTRIB_BITS can be used to copy the
maximum possible portion of rendering state.
- Specifies the connection to the X server.
- Specifies the source context.
- Specifies the destination context.
- Specifies which portions of src state are to be copied to
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
An implicit glFlush is done by
glXCopyContext if src is the current context for the
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.
- 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
- GLXBadContext is generated if either src
or dst is not a valid GLX context.