XtAddExposureToRegion(3) merge exposure events into a region

SYNTAX

void XtAddExposureToRegion(XEvent *event, Region region);

ARGUMENTS

event
Specifies a pointer to the Expose or GraphicsExpose event.
region
Specifies the region object (as defined in <X11/Xutil.h>).

DESCRIPTION

The XtAddExposureToRegion function computes the union of the rectangle defined by the exposure event and the specified region. Then, it stores the results back in region. If the event argument is not an Expose or GraphicsExpose event, XtAddExposureToRegion returns without an error and without modifying region.

This function is used by the exposure compression mechanism (see Section 7.9.3).