Blizzard Pass: Routine at 7428

7428: Draw Horizontal Run

Used by the routine at DispatchShape. Opcode F0 draws a horizontal run of pixels, patching its own length and shift bytes, then steps on by five.
HorizontalRun	7428	LD C,(IX+$01)
	742B	LD B,(IX+$02)
	742E	LD A,(IX+$03)
	7431	LD ($7424),A
	7434	LD A,(IX+$04)
	7437	LD ($73FE),A
	743A	CALL PixelRow_3
	743D	LD DE,$0005
	7440	ADD IX,DE
	7442	JP PictureRecord
HorizontalRun_0	7445	PUSH BC
	7446	PUSH HL
	7447	LD B,$00
	7449	PUSH HL
	744A	POP DE
HorizontalRun_1	744B	RR (HL)
	744D	INC HL
	744E	DJNZ HorizontalRun_1
	7450	EX DE,HL
	7451	RES 7,(HL)
	7453	JR NC,HorizontalRun_2
	7455	SET 7,(HL)
HorizontalRun_2	7457	POP HL
	7458	POP BC
	7459	INC H
	745A	DJNZ HorizontalRun_0
	745C	RET
This entry point is used by the routine at VerticalRun.
HorizontalRun_3	745D	PUSH BC
	745E	CALL PixelRow
	7461	LD B,$08
	7463	CALL HorizontalRun_0
	7466	POP BC
	7467	INC B
	7468	LD A,B
	7469	CP $00
	746B	JR NZ,HorizontalRun_3
	746D	RET