This function sets the low-level graphics pixel replacement rule. The valid replacement rules are
REP_FORCE 0.
REP_AND 1.
REP_OR 2.
REP_XOR 3.
REP_NOTFORCE 4.
REP_NOTAND 5.
REP_NOTOR 6.
REP_NOTXOR 7.
REP_BITBLT 8.