view src/video/ataricommon/SDL_ikbdinterrupt.S @ 1287:15a89a0c52bf

Date: Tue, 15 Feb 2005 21:28:48 +0900 (JST) From: "Michael Leonhard" Subject: [SDL] resize bug on Win32 and patch This is my first post to this mailing list. In this email I will detail a bug in the behavior of resizable SDL windows on Win32. Then I will explain the solution and provide a patch. Symptoms: Under Windows, an SDL display created with the SDL_RESIZABLE flag exhibits quirky behavior when being maximized. The window is resized to the proper size, but it is shifted upwards about half the height of the title bar. Similarly, a window whose origin is above the top of the screen will spontaneously move its upper-left origin upon being resized. After two such resize-induced moves, the title bar will be entirely off the top edge of the screen. Subsequently, when the mouse is clicked and released on the window border, the window will shrink its height spontaneously. This height shrinkage occurs even if the user did not resize the border. To observe this curious situation, please invoke: SDL-1.2.8/test/testwm.exe -resize Cause: A pair of integers, SDL_windowX and SDL_windowY, are defined in video/wincommon/SDL_sysevents.c. They are used by the DirectX video driver and the DIB video driver: video/windx5/SDL_dx5video.c video/windib/SDL_dibvideo.c As I understand the source code, the primary use of these variables is to create a rectangle that represents the surface area in CLIENT SPACE. Client space refers to a coordinate system that originates at the upper left corner of a Win32 Window's drawable area. This is just inside the window border and title bar. This client space rectangle, called bounds, is subsequently converted to screen space with a call to AdjustWindowRectEx. The problem is found in SDL's handling of the WM_WINDOWPOSCHANGED message. According to MSDN, "The WM_WINDOWPOSCHANGED message is sent to a window whose size, position, or place in the Z order has changed as a result of a call to the SetWindowPos function or another window-management function." I have confirmed that this message is indeed being sent to the SDL window when the mouse is clicked on the window border, even if the window border is not dragged. In video/wincommon/SDL_sysevents.c, on line 464, in response to the WM_WINDOWPOSCHANGED message, the (potentially) new client rectangle is obtained. This rectangle is translated into screen coordinates and THEN assigned to the SDL_windowX and Y variables. Thus screen coordinates are being assigned to client coordinate variables. Once this is understood, the solution is apparent: assign SDL_windowX and Y before translating the rectangle to screen coordinates. This is accomplished by the following patch. -Mike_L
author Sam Lantinga <slouken@libsdl.org>
date Sun, 29 Jan 2006 08:50:06 +0000
parents b6fdf299a2f3
children c9b51268668f
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id$";
#endif

/*
 *	IKBD 6301 interrupt routine
 *
 *	Patrice Mandin
 */

	.text

	.globl	_SDL_AtariIkbdInstall
	.globl	_SDL_AtariIkbdUninstall

	.globl	_SDL_AtariIkbd_keyboard
	.globl	_SDL_AtariIkbd_mouseb
	.globl	_SDL_AtariIkbd_mousex
	.globl	_SDL_AtariIkbd_mousey
	.globl	_SDL_AtariIkbd_joystick

	.globl	_SDL_AtariIkbd_enabled

/*--- Install our IKBD vector ---*/

_SDL_AtariIkbdInstall:
	moveml	d0-d1/a0-a1,sp@-

	| Disable interrupts

	movew	#0x2700,sr

	| Save MFP registers used for keyboard

	lea	0xfffffa00:w,a0
	btst	#6,a0@(0x09)
	sne		ikbd_ierb
	btst	#6,a0@(0x15)
	sne		ikbd_imrb

	| Set our routine

	movel	0x118:w,old_ikbd
	movel	#ikbd,0x118:w
	bset	#6,0xfffffa09:w	| IERB
	bset	#6,0xfffffa15:w	| IMRB

	| Set mouse relative mode

	moveb	#8,0xfffffc02:w

	| Reenable interrupts

	movew	#0x2300,sr

	| Interrupts done

	movew	#0xffff,_SDL_AtariIkbd_enabled

	moveml	sp@+,d0-d1/a0-a1
	rts

/*--- Uninstall our IKBD vector ---*/

_SDL_AtariIkbdUninstall:
	movel	a0,sp@-

	| Disable interrupts

	movew	#0x2700,sr

	| Restore previous MFP registers

	lea	0xfffffa00:w,a0

	bclr	#6,a0@(0x09)
	tstb	ikbd_ierb
	beqs	ikbd_restoreierb
	bset	#6,a0@(0x09)
ikbd_restoreierb:

	bclr	#6,a0@(0x15)
	tstb	ikbd_imrb
	beqs	ikbd_restoreimrb
	bset	#6,a0@(0x15)
ikbd_restoreimrb:

	movel	old_ikbd,0x118:w

	| Clear keyboard buffer

	lea	0xfffffc00:w,a0
ikbd_videbuffer:
	btst	#0,a0@
	beqs	ikbd_finbuffer
	tstb	a0@(0x02)
	bras	ikbd_videbuffer
ikbd_finbuffer:

	| Reenable interrupts

	movew	#0x2300,sr

	movel	sp@+,a0
	rts

	.bss

	.even
	.comm	ikbd_ierb,1
	.comm	ikbd_imrb,1

/*--- Our custom IKBD vector ---*/

	.text
	.even
	.ascii	"XBRA"
	.ascii	"LSDL"
	.comm	old_ikbd,4*1
ikbd:
	| Check if source is IKBD or MIDI
	btst	#0,0xfffffc00.w
	beqs	ikbd_oldmidi

	moveml	d0-d1/a0,sp@-
	moveb	0xfffffc02:w,d0

	| Joystick packet ?
	
	cmpb	#0xff,d0
	beqs	ikbd_yes_joystick

	| Mouse packet ?

	cmpb	#0xf8,d0
	bmis	ikbd_no_mouse
	cmpb	#0xfc,d0
	bpls	ikbd_no_mouse

	| Mouse packet, byte #1

ikbd_yes_mouse:
	andw	#3,d0
	movew	d0,_SDL_AtariIkbd_mouseb

	movel	#ikbd_mousex,0x118:w
	bras	ikbd_endit_stack

	| Joystick packet, byte #1

ikbd_yes_joystick:
	movel	#ikbd_joystick,0x118:w
	bras	ikbd_endit_stack

	| Keyboard press/release

ikbd_no_mouse:
	moveb	d0,d1
	lea		_SDL_AtariIkbd_keyboard,a0
	andw	#0x7f,d1
	tas		d0
	spl		a0@(0,d1:w)

	| End of interrupt

ikbd_endit_stack:
	moveml	sp@+,d0-d1/a0
ikbd_endit:
	bclr	#6,0xfffffa11:w
	rte

	| Call old MIDI interrupt

ikbd_oldmidi:
	movel	old_ikbd,sp@-
	rts

	| Mouse packet, byte #2

ikbd_mousex:

	| Check if source is IKBD or MIDI
	btst	#0,0xfffffc00.w
	beqs	ikbd_oldmidi

	movew	d0,sp@-

	moveb	0xfffffc02:w,d0
	extw	d0
	addw	d0,_SDL_AtariIkbd_mousex

	movew	sp@+,d0

	movel	#ikbd_mousey,0x118:w
	bras	ikbd_endit

	| Mouse packet, byte #3

ikbd_mousey:

	| Check if source is IKBD or MIDI
	btst	#0,0xfffffc00.w
	beqs	ikbd_oldmidi

	movew	d0,sp@-

	moveb	0xfffffc02:w,d0
	extw	d0
	addw	d0,_SDL_AtariIkbd_mousey

	movew	sp@+,d0

	movel	#ikbd,0x118:w
	bras	ikbd_endit

	| Joystick packet, byte #2

ikbd_joystick:

	| Check if source is IKBD or MIDI
	btst	#0,0xfffffc00.w
	beqs	ikbd_oldmidi

	moveb	0xfffffc02:w,_SDL_AtariIkbd_joystick+1

	movel	#ikbd,0x118:w
	bras	ikbd_endit

	.data
	
	.even
_SDL_AtariIkbd_enabled:
	.word	0

	.bss

	.even
	.comm	_SDL_AtariIkbd_keyboard,128
	.comm	_SDL_AtariIkbd_mousex,2
	.comm	_SDL_AtariIkbd_mousey,2
	.comm	_SDL_AtariIkbd_mouseb,2
	.comm	_SDL_AtariIkbd_joystick,2