machine 68020				;Optimize for 020

	* I hope you can cope with this :)

	* Size of routine: 72-80 bytes
	* (or 74 if I remove 2 instructions but get less
	* accuracy. Set the REMASL to 1 to enable it. If
	* it's allowed, PLEASE use that routine. If it isn't,
	* leave the REMASL untouched. With no asl's within the
	* calculation, it wraps in x when size is larger than
	* 125.)

	* CORRECTION adjusts the offsets so that radius 127 doesn't
	* get outside the buffer. Set this to zero if not needed.

	* Also choose of which of the ACCURACY modes you think
	* fits best. With ACCURACY disabled the routine will become
	* 2 bytes smaller (76/72).

	* Speed: On my 030/50 I can render approx. 7100 random
	* circles per second.

	* // ChiP ^ PowerLine

FASTEST = 0
CLEAR = 1
REMASL = 0
ACCURACY = 1
CORRECTION = 1

prg_DrawCircle

*** CUT HERE

* d0.l/d1.l - x/y
* d2.l - radius	(1-n(?))
* d3.b - color
* a0 - cbuffer

	* set initial positions

	add.l	d0,a0		;2
	asl.l	#8,d1		;6
	add.l	d1,a0		;2

	moveq.l	#0,d4		;2
	move.l	d2,d5		;2
	moveq.l	#1,d6		;2

	IFNE	ACCURACY

	asl.l	#1,d2		;6

	ENDIF

	sub.l	d2,d6		;2

.CircleLoop

	* calculate and set pixel position

	move.l	a0,a1		;2
	move.l	d5,d7		;2
	asl.l	#8,d7		;6
	sub.l	d7,a1		;2
	move.l	a1,a2		;2

	sub.l	d4,a1		;2
	add.l	d4,a2		;2

	* plot chunky pixels

	IFNE	CORRECTION

	move.b	d3,(1,a1)	;4
	move.b	d3,(a2)		;4
	move.b	d3,(1,a1,d7*2)	;9
	move.b	d3,(a2,d7*2)	;9

	ELSE

	move.b	d3,(a1)	;4
	move.b	d3,(a2)		;4
	move.b	d3,(a1,d7*2)	;9
	move.b	d3,(a2,d7*2)	;9

	ENDIF

	* calculate new positions

	move.l	d5,d7		;2
	add.l	d6,d7		;2
	bmi.s	.nofix_y	;8/4

	subq.l	#1,d5		;2
	bmi.s	.EndCircleLoop	;8/4

	move.l	d5,d7		;2

	IFEQ	REMASL

	asl.l	#2,d7		;6

	ENDIF

	sub.l	d7,d6		;2
	subq.l	#1,d6		;2

.nofix_y

	move.l	d4,d7		;2
	sub.l	d6,d7		;2
	bmi.s	.nofix_x	;8/4

	addq.l	#1,d4		;2
	move.l	d4,d7		;2

	IFEQ	REMASL

	asl.l	#2,d7		;6

	ENDIF

	add.l	d7,d6		;2
	subq.l	#1,d6		;2

.nofix_x

	bra.s	.CircleLoop	;8
.EndCircleLoop

*** CUT HERE

	rts			;11
.