section text,code

	xref	_Mask
	xref	_gplane

	procstart
	xdef	@GetWall
@GetWall:
	movem.l D2/D3,-(sp)

	move.w	D2,D0
	asr.w	#$03,D0

	mulu	#40,D3
	add.w	D3,D0

	not.b	D2

	lea	_Mask(A4),A0
	btst	D2,(A0,D0)
	bne	set

notset	moveq	#0,D0
	movem.l (sp)+,D2/D3
	rts

set	moveq	#1,D0
	movem.l (sp)+,D2/D3
	rts
	procend

	procstart
	xdef	@ClearWall
@ClearWall:
	movem.l D2/D3,-(sp)

	move.w	D2,D0
	asr.w	#$03,D0

	mulu	#40,D3
	add.w	D3,D0

	not.b	D2

	lea	_Mask(A4),A0
	bclr	D2,(A0,D0)

	movem.l (sp)+,D2/D3
	rts
	procend

	procstart
	xdef	@WritePixel
@WritePixel:
	movem.l D3,-(sp)

	move.w	D0,D3
	asr.w	#$03,D3

	mulu	#40,D1
	add.w	D1,D3

	not.b	D0

	moveq	#0,D1
	lea.l	_gplane(A4),A0
wploop	move.l	(A0)+,A1

	btst	D1,D2
	beq	wpclear

wpset	bset	D0,(A1,D3)
	bra	wpend

wpclear bclr	D0,(A1,D3)

wpend	addq.w	#1,D1
	cmp.w	#4,D1
	bmi	wploop

	movem.l (sp)+,D3
	rts
	procend

	END