view src/video/photon/SDL_ph_modes.c @ 765:4c2ba6161939

Editors Note: The original patch was modified to use SDL_Delay() instead of nanosleep because nanosleep may not be portable to all systems using SDL with the ALSA backend. This may be a moot point with the switch to blocking writes anyway... Date: Sat, 27 Dec 2003 21:47:36 +0100 From: Michel Daenzer To: Debian Bug Tracking System Subject: [SDL] Bug#225252: [PATCH] ALSA fixes Package: libsdl1.2debian-all Version: 1.2.6-2 Severity: normal Tags: patch For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU usage, interrupted sound and stuttering in some games here. Taking a nanosleep whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more efficient to use blocking mode for the actual sound playback. Feedback from the SDL and ALSA lists appreciated. The patch also fixes the default ALSA device to be used.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 04 Jan 2004 15:40:50 +0000
parents 04dd6c6d7c30
children b8d311d90021
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

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

    key1 = mode_info.width * mode_info.height;

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

    key2 = mode_info.width * mode_info.height;

    if (key1 > key2)
    {
        return 1;
    }
    else
    {
        if (key1 == key2)
        {
           return 0;
        }
        else
        {
            return -1;
        }
    }
}

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;

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

    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)
{
    PgDisplaySettings_t settings;
    int mode;

    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;
            }
        }

        /* 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;

        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
#endif /* HAVE_OPENGL */
                return 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
#endif /* HAVE_OPENGL */
           return 0;
        }
        else
        {
            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;
}