Typically, the handling routine would allocate more memory for the new DC region (when necessary) and call GreGetClipRects (see GreGetClipRects ) to get the set of rectangles that define the new DC region. Also (for display devices only), the handling routine must clear the HDC_IS_DIRTY flag.

On completion, the handling routine must re-dispatch this call to the graphics engine using the pointer supplied in the default dispatch table.