X11R4

NAME

XtAddExposureToRegion − merge exposure events into a region

SYNOPSIS

void XtAddExposureToRegion(event, region)
  XEvent ∗event;
  Region region;

PARAMETERS

eventSpecifies a pointer to the Expose or GraphicsExpose event.

regionSpecifies 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). 

RELATED INFORMATION

X Window System Toolkit: The Complete Programmer’s Guide and Specification, Paul J. Asente and Ralph Swick
X Window System: The Complete Reference, Second Edition, Robert W. Scheifler and James Gettys