view src/video/photon/SDL_ph_modes.c @ 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 f72cc0c7305f
children c07c6ef7c93e
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2004 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

#include "SDL_error.h"
#include "SDL_ph_modes_c.h"

static unsigned long key1, key2;
static PgVideoModeInfo_t mode_info;
static PgVideoModes_t mode_list;

/* The current list of available video modes */
SDL_Rect  SDL_modelist[PH_MAX_VIDEOMODES];
SDL_Rect* SDL_modearray[PH_MAX_VIDEOMODES];

static int compare_modes_by_res(const void* mode1, const void* mode2)
{
    PgVideoModeInfo_t mode1_info;
    PgVideoModeInfo_t mode2_info;

    if (PgGetVideoModeInfo(*(unsigned short*)mode1, &mode1_info) < 0)
    {
        return 0;
    }

    if (PgGetVideoModeInfo(*(unsigned short*)mode2, &mode2_info) < 0)
    {
        return 0;
    }

    if (mode1_info.width == mode2_info.width)
    {
        return mode2_info.height - mode1_info.height;
    }
    else
    {
        return mode2_info.width - mode1_info.width;
    }
}

SDL_Rect **ph_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags)
{
    int i = 0;
    int j = 0;
    SDL_Rect Amodelist[PH_MAX_VIDEOMODES];

    for (i=0; i<PH_MAX_VIDEOMODES; i++)
    {
        SDL_modearray[i]=&SDL_modelist[i];
    }

    if (PgGetVideoModeList(&mode_list) < 0)
    {
       SDL_SetError("ph_ListModes(): PgGetVideoModeList() function failed !\n");
       return NULL;
    }

    mode_info.bits_per_pixel = 0;

    for (i=0; i < mode_list.num_modes; i++) 
    {
        if (PgGetVideoModeInfo(mode_list.modes[i], &mode_info) < 0)
        {
            SDL_SetError("ph_ListModes(): PgGetVideoModeInfo() function failed on mode: 0x%X.\n", mode_list.modes[i]);
            return NULL;
        }
        if(mode_info.bits_per_pixel == format->BitsPerPixel)
        {
            Amodelist[j].w = mode_info.width;
            Amodelist[j].h = mode_info.height;
            Amodelist[j].x = 0;
            Amodelist[j].y = 0;
            j++;	
        }
    }
	
    /* reorder biggest for smallest, assume width dominates */

    for(i=0; i<j; i++)
    {
        SDL_modelist[i].w = Amodelist[j - i - 1].w;
        SDL_modelist[i].h = Amodelist[j - i - 1].h;
        SDL_modelist[i].x = Amodelist[j - i - 1].x;
        SDL_modelist[i].y = Amodelist[j - i - 1].y;
    }
    SDL_modearray[j]=NULL;
	
    return SDL_modearray;
}

void ph_FreeVideoModes(_THIS)
{
   return;
}

/* return the mode associated with width, height and bpp */
/* if there is no mode then zero is returned             */
int ph_GetVideoMode(int width, int height, int bpp)
{
    int i;
    int modestage=0;
    int closestmode=0;

    if (PgGetVideoModeList(&mode_list) < 0)
    {
        return -1;
    }

    /* special case for the double-sized 320x200 mode */
    if ((width==640) && (height==400))
    {
       modestage=1;
    }

    /* search list for exact match */
    for (i=0; i<mode_list.num_modes; i++)
    {
        if (PgGetVideoModeInfo(mode_list.modes[i], &mode_info) < 0)
        {
            return 0;
        }

        if ((mode_info.width == width) && (mode_info.height == height) && 
            (mode_info.bits_per_pixel == bpp))
        {
            return mode_list.modes[i];
        }
        else
        {
           if ((modestage) && (mode_info.width == width) && (mode_info.height == height+80) && 
               (mode_info.bits_per_pixel == bpp))
           {
              modestage=2;
              closestmode=mode_list.modes[i];
           }
        }
    }

    /* if we are here, then no 640x400xbpp mode found and we'll emulate it via 640x480xbpp mode */
    if (modestage==2)
    {
       return closestmode;
    }

    return (i == mode_list.num_modes) ? 0 : mode_list.modes[i];
}

/* return the mode associated with width, height and bpp               */
/* if requested bpp is not found the mode with closest bpp is returned */
int get_mode_any_format(int width, int height, int bpp)
{
    int i, closest, delta, min_delta;

    if (PgGetVideoModeList(&mode_list) < 0)
    {
        return -1;
    }

    qsort(mode_list.modes, mode_list.num_modes, sizeof(unsigned short), compare_modes_by_res);

    for(i=0;i<mode_list.num_modes;i++)
    {
        if (PgGetVideoModeInfo(mode_list.modes[i], &mode_info) < 0)
        {
            return 0;
        }
        if ((mode_info.width == width) && (mode_info.height == height))
        {
           break;
        }
    }

    if (i<mode_list.num_modes)
    {
        /* get closest bpp */
        closest = i++;
        if (mode_info.bits_per_pixel == bpp)
        {
            return mode_list.modes[closest];
        }

        min_delta = abs(mode_info.bits_per_pixel - bpp);

        while(1)
        {
            if (PgGetVideoModeInfo(mode_list.modes[i], &mode_info) < 0)
            {
                return 0;
            }

            if ((mode_info.width != width) || (mode_info.height != height))
            {
                break;
            }
            else
            {
                if (mode_info.bits_per_pixel == bpp)
                {
                    closest = i;
                    break;
                }
                else
                {
                    delta = abs(mode_info.bits_per_pixel - bpp);
                    if (delta < min_delta)
                    {
                        closest = i;
                        min_delta = delta;
                    }
                    i++;
                }
            }
        }
        return mode_list.modes[closest];
    }

    return 0;
}

int ph_ToggleFullScreen(_THIS, int on)
{
    return -1;
}

int ph_EnterFullScreen(_THIS, SDL_Surface* screen, int fmode)
{
    PgDisplaySettings_t settings;
    int mode;
    char* refreshrate;
    int refreshratenum;

    if (!currently_fullscreen)
    {
        /* Get the video mode and set it */
        if (screen->flags & SDL_ANYFORMAT)
        {
            if ((mode = get_mode_any_format(screen->w, screen->h, screen->format->BitsPerPixel)) == 0)
            {
                SDL_SetError("ph_EnterFullScreen(): can't find appropriate video mode !\n");
                return 0;
            }
        }
        else
        {
            if ((mode = ph_GetVideoMode(screen->w, screen->h, screen->format->BitsPerPixel)) == 0)
            {
                SDL_SetError("ph_EnterFullScreen(): can't find appropriate video mode !\n");
                return 0;
            }
            if (PgGetVideoModeInfo(mode, &mode_info) < 0)
            {
                SDL_SetError("ph_EnterFullScreen(): can't get video mode capabilities !\n");
                return 0;
            }
            if (mode_info.height != screen->h)
            {
               if ((mode_info.height==480) && (screen->h==400))
               {
                  videomode_emulatemode=1;
               }
            }
            else
            {
               videomode_emulatemode=0;
            }
        }

        /* save old video mode caps */
        PgGetVideoMode(&settings);
        old_video_mode=settings.mode;
        old_refresh_rate=settings.refresh;

        /* setup new video mode */
        settings.mode = mode;
        settings.refresh = 0;
        settings.flags = 0;

        refreshrate=getenv("SDL_PHOTON_FULLSCREEN_REFRESH");
        if (refreshrate!=NULL)
        {
           if (sscanf(refreshrate, "%d", &refreshratenum)==1)
           {
               settings.refresh = refreshratenum;
           }
        }

        if (PgSetVideoMode(&settings) < 0)
        {
            SDL_SetError("ph_EnterFullScreen(): PgSetVideoMode() call failed !\n");
            return 0;
        }

        if (this->screen)
        {
            if ((this->screen->flags & SDL_OPENGL)==SDL_OPENGL)
            {
#ifdef HAVE_OPENGL
    #if (_NTO_VERSION < 630)
                return 0;
    #endif /* 6.3.0 */
#else
                return 0;
#endif /* HAVE_OPENGL */
            }
        }

        if (fmode==0)
        {
            if (OCImage.direct_context==NULL)
            {
                OCImage.direct_context=(PdDirectContext_t*)PdCreateDirectContext();
                if (!OCImage.direct_context)
                {
                    SDL_SetError("ph_EnterFullScreen(): Can't create direct context !\n");
                    ph_LeaveFullScreen(this);
                    return 0;
                }
            }
            OCImage.oldDC=PdDirectStart(OCImage.direct_context);
        }

        currently_fullscreen = 1;
    }
    PgFlush();

    return 1;
}

int ph_LeaveFullScreen(_THIS)
{
    PgDisplaySettings_t oldmode_settings;
       
    if (currently_fullscreen)
    {
        if ((this->screen) && ((this->screen->flags & SDL_OPENGL)==SDL_OPENGL))
        {
#ifdef HAVE_OPENGL
    #if (_NTO_VERSION < 630)
            return 0;
    #endif /* 6.3.0 */
#else
            return 0;
#endif /* HAVE_OPENGL */
        }

        /* release routines starts here */
        {
            if (OCImage.direct_context)
            {
                PdDirectStop(OCImage.direct_context);
                PdReleaseDirectContext(OCImage.direct_context);
                OCImage.direct_context=NULL;
            }
            if (OCImage.oldDC)
            {
                PhDCSetCurrent(OCImage.oldDC);
                OCImage.oldDC=NULL;
            }

            currently_fullscreen=0;

            /* Restore old video mode */
            if (old_video_mode != -1)
            {
                oldmode_settings.mode = (unsigned short) old_video_mode;
                oldmode_settings.refresh = (unsigned short) old_refresh_rate;
                oldmode_settings.flags = 0;
                
                if (PgSetVideoMode(&oldmode_settings) < 0)
                {
                    SDL_SetError("Ph_LeaveFullScreen(): PgSetVideoMode() function failed !\n");
                    return 0;
                }
            }

            old_video_mode=-1;
            old_refresh_rate=-1;
        }
    }
    return 1;
}