glXSelectEvent(3G) OpenGL Reference - GLX glXSelectEvent(3G)NAMEglXSelectEvent - select GLX events for a window or a GLX pixel buffer
C SPECIFICATION
void glXSelectEvent( Display *dpy,
GLXDrawable drawable,
unsigned long event_mask )
PARAMETERS
dpy Specifies the connection to the X server.
drawable Specifies a GLX drawable. Must be a GLX pixel buffer or a
window.
event_mask Specifies the events to be returned for drawable.
DESCRIPTIONglXSelectEvent sets the GLX event mask for a GLX pixel buffer or a
window. Calling glXSelectEvent overrides any previous event mask that was
set by the client for drawable. Note that it does not affect the event
masks that other clients may have specified for drawable since each
client rendering to drawable has a separate event mask for it.
Currently, only one GLX event, GLX_PBUFFER_CLOBBER_MASK, can be selected.
The following data is returned to the client when a
GLX_PBUFFER_CLOBBER_MASK event occurs:
typdef struct {
int event_type; /* GLX_DAMAGED or GLX_SAVED */
int draw_type; /* GLX_WINDOW or GLX_PBUFFER */
unsigned long serial; /* # of last request processed by server */
Bool send_event; /* true if this came for SendEvent request */
Display *display; /* display the event was read from */
GLXDrawable drawable; /* i.d. of Drawable */
unsigned int buffer_mask; /* mask indicating affectedbuffers */
int x, y;
int width, height;
int count; /* if nonzero, at least this many more */
} GLXPbufferClobberEvent;
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glXSelectEvent(3G) OpenGL Reference - GLX glXSelectEvent(3G)
The valid bit masks used in buffer_mask are:
_____________________________________________________
Bitmask Corresponding Buffer
_____________________________________________________
GLX_FRONT_LEFT_BUFFER_BIT Front left color buffer
GLX_FRONT_RIGHT_BUFFER_BIT Front right color buffer
GLX_BACK_LEFT_BUFFER_BIT Back left color buffer
GLX_BACK_RIGHT_BUFFER_BIT Back right color buffer
GLX_AUX_BUFFERS_BIT Auxillary buffer
GLX_DEPTH_BUFFER_BIT Depth buffer
GLX_STENCIL_BUFFER_BIT Stencil buffer
GLX_ACCUM_BUFFER_BIT Accumulation buffer
_____________________________________________________
A single X server operation can cause several buffer clobber events to be
sent. (e.g., a single GLX pixel buffer may be damaged and cause multiple
buffer clobber events to be generated). Each event specifies one region
of the GLX drawable that was affected by the X Server operation. The
buffer_mask field indicates which color buffers and ancillary buffers
were affected. All the buffer clobber events generated by a single X
server action are guaranteed to be contiguous in the event queue. The
conditions under which this event is generated and the event_type varies,
depending on the type of the GLX drawable.
When the GLX_AUX_BUFFERS_BIT is set in buffer_mask, then aux_buffer is
set to indicate which buffer was affected. If more than one aux buffer
was affected, then additional events are generated as part of the same
contiguous event group. Each additional event will have only the
GLX_AUX_BUFFERS_BIT set in buffer_mask, and the aux_buffer field will be
set appropriately. For nonstereo drawables, GLX_FRONT_LEFT_BUFFER_BIT and
GLX_BACK_LEFT_BUFFER_BIT are used to specify the front and back color
buffers.
For preserved GLX pixel buffers, a buffer clobber event with type
GLX_SAVED is generated whenever the contents of the GLX pixel buffer is
moved out of offscreen memory. The event(s) describes which portions of
the GLX pixel buffer were affected. Clients who receive many buffer
clobber events, referring to different save actions, should consider
freeing the GLX pixel buffer resource in order to prevent the system from
thrashing due to insufficient resources.
For an unpreserved GLXPbuffer, a buffer clobber event, with type
GLX_DAMAGED, is generated whenever a portion of the GLX pixel buffer
becomes invalid. The client may wish to regenerate the invalid portions
of the GLX pixel buffer.
For Windows, buffer clobber events, with type GLX_SAVED, occur whenever
an ancillary buffer, associated with the window, gets clobbered or moved
out of offscreen memory. The event contains information indicating which
color buffers and ancillary buffers-and which portions of those buffers-
were affected.
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glXSelectEvent(3G) OpenGL Reference - GLX glXSelectEvent(3G)NOTESglXSelectEvent 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
GLXBadDrawable is generated if drawable is not a valid window or a valid
GLX pixel buffer.
ASSOCIATED GETS
glXGetSelectedEvent
SEE ALSO
glXCreatePbuffer
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