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xcb_damage_create(3) XCB Requests xcb_damage_create(3)
NAME
xcb_damage_create - Creates a Damage object to monitor changes to a
drawable.
SYNOPSIS
#include <xcb/damage.h>
Request function
xcb_void_cookie_t xcb_damage_create(xcb_connection_t *conn,
xcb_damage_damage_t damage, xcb_drawable_t drawable,
uint8_t level);
REQUEST ARGUMENTS
conn The XCB connection to X11.
damage The ID with which you will refer to the new Damage object,
created by xcb_generate_id.
drawable The ID of the drawable to be monitored.
level The level of detail to be provided in Damage events.
DESCRIPTION
This creates a Damage object to monitor changes to a drawable, and
specifies the level of detail to be reported for changes.
We call changes made to pixel contents of windows and pixmaps 'damage'
throughout this extension.
Damage accumulates as drawing occurs in the drawable. Each drawing
operation are guaranteed to include the set of pixels modified by each
operation, but may include significantly more than just those pixels.
The desire is for the damage to strike a balance between the number of
rectangles reported and the extraneous area included. A reasonable
goal is for each primitive object drawn (line, string, rectangle) to be
represented as a single rectangle and for the damage area of the
operation to be the union of these rectangles.
The DAMAGE extension allows applications to either receive the raw
rectangles as a stream of events, or to have them partially processed
within the X server to reduce the amount of data transmitted as well as
reduce the processing latency once the repaint operation has started.
The Damage object holds any accumulated damage region and reflects the
relationship between the drawable selected for damage notification and
the drawable for which damage is tracked.
RETURN VALUE
Returns an xcb_void_cookie_t. Errors (if any) have to be handled in the
event loop.
If you want to handle errors directly with xcb_request_check instead,
use xcb_damage_create_checked. See xcb-requests(3) for details.
ERRORS
This request does never generate any errors.
X Version 11 libxcb 1.17.0 xcb_damage_create(3)