* 
* Copyright (C) 1996-1997 Id Software, Inc. 
* 
* This program is free software; you can redistribute it and/or 
* modify it under the terms of the GNU General Public License 
* as published by the Free Software Foundation; either version 2 
* of the License, or (at your option) any later version. 
* 
* This program is distributed in the hope that it will be useful, 
* but WITHOUT ANY WARRANTY; without even the implied warranty of 
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.   
* 
* See the GNU General Public License for more details. 
* 
* You should have received a copy of the GNU General Public License 
* along with this program; if not, write to the Free Software 
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. 
* 

**
** vid_turboupd68k.s
**
** turbo video buffer update for Quake-Amiga68k (68040/060 only!)
**
** Written by Frank Wille <frank@phoenix.owl.de>
**

	code

	xdef	_TurboUpdate68k
	xdef	_ChunkyCopy68k


	cnop	0,4
_ChunkyCopy68k:
; 4(sp) = ModeScreen
; 8(sp) = gfxaddr
; 12(sp) = vid_buffer
; rest is irrelevant

	movem.l	d2-d4,-(sp)
	move.l	12+4(sp),a0
	moveq	#0,d1
	move.l	8(a0),d4	; ms.bpr
	moveq	#0,d0
	move.l	544(a0),d2	; ms.SCREENWIDTH
	mulu	d4,d1
	move.l	548(a0),d3	; ms.SCREENHEIGHT
	sub.l	d2,d4
	move.l	12+8(sp),a1
	lsr.l	#6,d2
	move.l	12+12(sp),a0
	add.l	d0,a1
	add.l	d1,a1
1$:	move.l	d2,d0
2$:	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	subq.l	#1,d0
	bne.b	2$
	add.l	d4,a1
	subq.l	#1,d3
	bne.b	1$
	movem.l	(sp)+,d2-d4
	rts


	cnop	0,4
_TurboUpdate68k:
; a0 = vid_buffer
; a1 = gfxaddr
; d4 = bytesperrow
; d0 = x
; d1 = y
; d2 = width
; d3 = height

	mulu	d4,d1
	add.l	d0,a1
	sub.l	d2,d4
	add.l	d1,a1
	lsr.l	#6,d2
1$:	move.l	d2,d0
2$:	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	move16	(a0)+,(a1)+
	subq.l	#1,d0
	bne.b	2$
	add.l	d4,a1
	subq.l	#1,d3
	bne.b	1$
	rts