Knight Lore: Routine at C0DD

C0DD: Put the charm under the player

Used by the routine at room_to_drop. The charm takes the player's x, y and z, and the player -- both records, at $5C08 and $5C28 -- goes up 12 units, the height of a charm, so the player ends up standing on it. This is how charms can be stacked into steps.
place_under_player	C0DD	PUSH HL	HL = $5BE5: the rest of the slot, for drop_object
	C0DE	LD BC,$0003	copy x, y, z from the player to the charm
	C0E1	PUSH IX
	C0E3	POP HL
	C0E4	PUSH IY
	C0E6	POP DE
	C0E7	INC DE
	C0E8	INC HL
	C0E9	LDIR
	C0EB	LD A,(IX+$03)	lift both of the player's records by 12
	C0EE	ADD A,$0C
	C0F0	LD (IX+$03),A
	C0F3	LD A,(IX+$23)
	C0F6	ADD A,$0C
	C0F8	LD (IX+$23),A
	C0FB	PUSH IX	the charm's screen position
	C0FD	PUSH IY
	C0FF	POP IX
	C101	CALL calc_pixel_XY
	C104	POP IX