Chase H.Q.: Routine at B76C

B76C: Masked sprite plotter which flips

Used by the routine at draw_object_right.
plot_masked_sprite_flipped	B76C	LD D,$00	DE = A
	B76E	LD E,A	DE = A
	B76F	ADD HL,DE	HL += DE
This entry point is used by the routine at sub_b67c.
plot_masked_sprite_flipped_0	B770	EX DE,HL
	B771	LD ($B792),SP	Save SP for restoration on exit
	B775	LD IX,$B79C	Point IX at jump table
	B779	CPL	Subtract 8
	B77A	ADD A,$09	Subtract 8
	B77C	RLCA	Multiply by 8 -- length of jump table sequences
	B77D	RLCA
	B77E	RLCA
	B77F	LD C,A	Add to IX
	B780	LD B,$00
	B782	ADD IX,BC
	B784	LD H,$EF	H = $EF
	B786	EXX
	B787	LD D,$00
	B789	JR plot_masked_sprite_flipped_4
plot_masked_sprite_flipped_1	B78B	EX AF,AF'
	B78C	LD E,A
plot_masked_sprite_flipped_2	B78D	EX AF,AF'
	B78E	EXX	Bank
	B78F	DJNZ plot_masked_sprite_flipped_3	Next scanline
	B791	LD SP,$0000	Restore SP (self modified)
	B794	RET	Return
plot_masked_sprite_flipped_3	B795	ADD HL,DE	Calculate address of next bitmap scanline
plot_masked_sprite_flipped_4	B796	LD SP,HL	Put it in SP (so we can use POP for speed)
	B797	EXX	Unbank
	B798	LD A,E
	B799	EX AF,AF'
	B79A	JP (IX)	Jump
pmsf_jumptable	B79C	POP BC	Load a bitmap and mask pair (B,C)
	B79D	LD L,C	Set flip table index (assuming table is aligned)
	B79E	LD A,(DE)	Load the screen pixels
	B79F	AND (HL)	AND screen pixels with flipped mask
	B7A0	LD L,B	Set flip table index
	B7A1	OR (HL)	OR in new flipped pixels
	B7A2	LD (DE),A	Store back to the screen
	B7A3	DEC E	Move to next screen pixel (downwards in memory)
	B7A4	POP BC	<Repeat 9 times>
	B7A5	LD L,C
	B7A6	LD A,(DE)
	B7A7	AND (HL)
	B7A8	LD L,B
	B7A9	OR (HL)
	B7AA	LD (DE),A
	B7AB	DEC E
	B7AC	POP BC
	B7AD	LD L,C
	B7AE	LD A,(DE)
	B7AF	AND (HL)
	B7B0	LD L,B
	B7B1	OR (HL)
	B7B2	LD (DE),A
	B7B3	DEC E
	B7B4	POP BC
	B7B5	LD L,C
	B7B6	LD A,(DE)
	B7B7	AND (HL)
	B7B8	LD L,B
	B7B9	OR (HL)
	B7BA	LD (DE),A
	B7BB	DEC E
	B7BC	POP BC
	B7BD	LD L,C
	B7BE	LD A,(DE)
	B7BF	AND (HL)
	B7C0	LD L,B
	B7C1	OR (HL)
	B7C2	LD (DE),A
	B7C3	DEC E
	B7C4	POP BC
	B7C5	LD L,C
	B7C6	LD A,(DE)
	B7C7	AND (HL)
	B7C8	LD L,B
	B7C9	OR (HL)
	B7CA	LD (DE),A
	B7CB	DEC E
	B7CC	POP BC
	B7CD	LD L,C
	B7CE	LD A,(DE)
	B7CF	AND (HL)
	B7D0	LD L,B
	B7D1	OR (HL)
	B7D2	LD (DE),A
	B7D3	DEC E
	B7D4	POP BC
	B7D5	LD L,C
	B7D6	LD A,(DE)
	B7D7	AND (HL)
	B7D8	LD L,B
	B7D9	OR (HL)
	B7DA	LD (DE),A
	B7DB	LD A,D
	B7DC	DEC D
	B7DD	AND $0F
	B7DF	JP NZ,plot_masked_sprite_flipped_1
	B7E2	EX AF,AF'
	B7E3	SUB $20
	B7E5	LD E,A
	B7E6	JR C,plot_masked_sprite_flipped_2	Loop
	B7E8	LD A,D
	B7E9	ADD A,$10
	B7EB	LD D,A
	B7EC	JP plot_masked_sprite_flipped_2	Loop