NAME
        SwapBitsRastPortClipRect -- Swap bits between common bitmap
                                    and obscured cliprect

    SYNOPSIS
        SwapBitsRastPortClipRect( rp, cr )
                                  a0  a1

        void SwapBitsRastPortClipRect( struct rastport *, struct cliprect *);

    FUNCTION
        Support routine useful for those that need to do some
        operations not done by the layer library.  Allows programmer
        to swap the contents of a small bitmap with a subsection of
        the display. This is accomplished without using extra memory.
        The bits in the display rastport are exchanged with the
        bits in the ClipRect's bitmap.

        Note: the cliprect structures which the layer library allocates are
        actually a little bigger than those described in the graphics/clip.h
        include file.  So be warned that it is not a good idea to have
        instances of cliprects in your code.

    INPUTS
        rp - pointer to rastport
        cr - pointer to cliprect to swap bits with

    NOTE
        Because the blit operation started by this function is done asynchronously,
        it is imperative that a waitblit() be performed before releasing or using
        the processor to modify any of the associated structures.

    BUGS

    SEE ALSO
        graphics/clip.h, graphics/rastport.h, graphics/clip.h