xcreateregion(3) [centos man page]

XCreateRegion(3)						  XLIB FUNCTIONS						  XCreateRegion(3)

NAME

       XCreateRegion, XSetRegion, XDestroyRegion - create or destroy regions

SYNTAX

       Region XCreateRegion(void);

       int XSetRegion(Display *display, GC gc, Region r);

       int XDestroyRegion(Region r);

ARGUMENTS

       display	 Specifies the connection to the X server.

       gc	 Specifies the GC.

       r	 Specifies the region.

DESCRIPTION

       The XCreateRegion function creates a new empty region.

       The XSetRegion function sets the clip-mask in the GC to the specified region.  The region is specified relative to the drawable's origin.
       The resulting GC clip origin is implementation-dependent.  Once it is set in the GC, the region can be destroyed.

       The XDestroyRegion function deallocates the storage associated with a specified region.

SEE ALSO

       XEmptyRegion(3), XIntersectRegion(3)
       Xlib - C Language X Interface

X Version 11							   libX11 1.6.0 						  XCreateRegion(3)

XPolygonRegion()														  XPolygonRegion()

Name
  XPolygonRegion - generate a region from points in a polygon.

Synopsis
  Region XPolygonRegion(points, n, fill_rule)
	XPoint points[];
	int n;
	int fill_rule;

Arguments
  points    Specifies a pointer to an array of points.

  n	    Specifies the number of points in the polygon.

  fill_rule Specifies  whether	areas overlapping an odd number of times should be part of the region (WindingRule) or not part of the region
	    (EvenOddRule).  See Volume One, Chapter 5, The Graphics Context, for a description of the fill rule.

Returns
  The created region.

Description
  XPolygonRegion() creates a region defined by connecting the specified points, and returns a pointer to be used to refer to the region.

  Regions are located relative to a point (the region origin) which is common to all regions.  In XPolygonRegion(), the coordinates specified
  in points are relative to the region origin.	By specifying all points relative to the drawable in which they will be used, the region ori-
  gin can be coincident with the drawable origin.  It is up to the application whether to interpret the location of the region relative to  a
  drawable or not.

  If  the  region  is to be used as a clip_mask by calling XSetRegion(), the upper-left corner of the region relative to the drawable used in
  the graphics request will be at (xoffset + clip_x_origin, yoffset + clip_y_origin), where xoffset and yoffset are the offset of the  region
  (if  any)  and  clip_x_origin  and clip_y_origin are elements of the GC used in the graphics request.  The fill_rule can be either of these
  values:

  EvenOddRule	 Areas overlapping an odd number of times are not part of the region.

  WindingRule	 Overlapping areas are always filled.

  For more information on structures, see Volume One, Chapter 6, Drawing Graphics and Text.

Structures
  Region is a pointer to an opaque structure type.

See Also
  XClipBox(), XCreateRegion(),	XDestroyRegion(),  XEmptyRegion(),  XEqualRegion(),  XIntersectRegion(),  XOffsetRegion(),  XPointInRegion(),
  XRectInRegion(), XSetRegion(), XShrinkRegion(), XSubtractRegion(), XUnionRectWithRegion(), XUnionRegion(), XXorRegion().

Xlib - Regions															  XPolygonRegion()