view src/video/ps2gs/SDL_gsvideo.h @ 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 e8157fcb3114
children c9b51268668f
line wrap: on
line source

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

#ifndef _SDL_gsvideo_h
#define _SDL_gsvideo_h

#include <sys/types.h>
#include <termios.h>
#include <linux/ps2/dev.h>
#include <linux/ps2/gs.h>

#include "SDL_mouse.h"
#include "SDL_mutex.h"
#include "SDL_sysvideo.h"

/* Hidden "this" pointer for the video functions */
#define _THIS	SDL_VideoDevice *this


/* Private display data */
struct SDL_PrivateVideoData {
	/* Gotta love that simple PS2 graphics interface. :) */
	int console_fd;
	int memory_fd;
	struct ps2_screeninfo saved_vinfo;

	/* Ye olde linux keyboard code */
	int current_vt;
	int saved_vt;
	int keyboard_fd;
	int saved_kbd_mode;
	struct termios saved_kbd_termios;

	/* Ye olde linux mouse code */
	int mouse_fd;
	int cursor_drawn;

	/* The memory mapped DMA area and associated variables */
	caddr_t mapped_mem;
	int pixels_len;
	int mapped_len;
	struct ps2_image screen_image;
	int screen_image_size;
	unsigned long long *head_tags_mem;
	unsigned long long *image_tags_mem;
	unsigned long long *tex_tags_mem;
	unsigned long long *scale_tags_mem;
	int dma_pending;
};
/* Old variable names */
#define console_fd		(this->hidden->console_fd)
#define memory_fd		(this->hidden->memory_fd)
#define saved_vinfo		(this->hidden->saved_vinfo)
#define current_vt		(this->hidden->current_vt)
#define saved_vt		(this->hidden->saved_vt)
#define keyboard_fd		(this->hidden->keyboard_fd)
#define saved_kbd_mode		(this->hidden->saved_kbd_mode)
#define saved_kbd_termios	(this->hidden->saved_kbd_termios)
#define mouse_fd		(this->hidden->mouse_fd)
#define cursor_drawn		(this->hidden->cursor_drawn)
#define mapped_mem		(this->hidden->mapped_mem)
#define pixels_len		(this->hidden->pixels_len)
#define mapped_len		(this->hidden->mapped_len)
#define screen_image		(this->hidden->screen_image)
#define screen_image_size	(this->hidden->screen_image_size)
#define head_tags_mem		(this->hidden->head_tags_mem)
#define image_tags_mem		(this->hidden->image_tags_mem)
#define tex_tags_mem		(this->hidden->tex_tags_mem)
#define scale_tags_mem		(this->hidden->scale_tags_mem)
#define dma_pending		(this->hidden->dma_pending)

/* Shared between the mouse and video code for screen update scaling */
extern int scaleimage_nonblock(int fd,
                               unsigned long long *tm, unsigned long long *sm);
#endif /* _SDL_gsvideo_h */