Marsport: Routine at 9EFA

9EFA: Draw a junction or corner

Used by the routine at _a345.
Bg_DrawJunction	9EFA	LD ($5BE0),HL
	9EFD	LD L,(IX+$02)	Get the bitmap to draw.
	9F00	CALL Bitmap_GetData
	9F03	LD HL,($5BE0)
	9F06	LD A,(Bmp_DataBufferHeight)	Get height if image in pixels.
	9F09	AND $7F
	9F0B	RLA
	9F0C	RLA
	9F0D	RLA
	9F0E	LD E,A
	9F0F	LD D,$00
	9F11	ADD HL,DE
	9F12	EX DE,HL
	9F13	LD HL,$0050
	9F16	AND A
	9F17	SBC HL,DE
	9F19	RET C
	9F1A	ADD HL,HL
	9F1B	LD E,L
	9F1C	LD D,H
	9F1D	ADD HL,HL
	9F1E	ADD HL,HL
	9F1F	ADD HL,HL
	9F20	ADD HL,HL
	9F21	ADD HL,DE
	9F22	LD DE,($A339)
	9F26	ADD HL,DE
	9F27	LD ($A33B),HL
	9F2A	LD E,(IX+$00)	Calculate distance between camera and the item in Walk Units in the direction of movement.
	9F2D	LD D,(IX+$01)
	9F30	LD HL,(Position_EW)
	9F33	LD A,(Stage_Compass)
	9F36	BIT 0,A
	9F38	JR Z,Bg_DrawJunction_0
	9F3A	LD HL,(Position_NS)
Bg_DrawJunction_0	9F3D	CALL abs_hl_de
	9F40	EX DE,HL
	9F41	LD A,(Bmp_DataBufferWidth)
	9F44	AND $7F
	9F46	LD L,A
	9F47	LD H,$00
	9F49	LD A,(Hero_LastDir)
	9F4C	CP $02
	9F4E	JR Z,Bg_DrawJunction_1
	9F50	EX DE,HL
	9F51	AND A
	9F52	SBC HL,DE
	9F54	EX DE,HL
	9F55	LD HL,$0020
	9F58	SBC HL,DE
	9F5A	JR Bg_DrawJunction_2
Bg_DrawJunction_1	9F5C	ADD HL,DE	Add width to distance.
	9F5D	LD DE,$0022	Subtracting distance between camera and left hand side of screen will leaving us the amount of the item that is off camera.
	9F60	AND A
	9F61	SBC HL,DE
Bg_DrawJunction_2	9F63	SRL H	Convert from Walk Units to pixels will give us the number of chars in the bitmap that are not visible.
	9F65	RR L
	9F67	EX DE,HL
Fall thru, to draw the visible column of bitmap.