view docs/html/sdllistmodes.html @ 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 e5bc29de3f0a
children 355632dca928
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><H1
><A
NAME="SDLLISTMODES"
>SDL_ListModes</A
></H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN776"
></A
><H2
>Name</H2
>SDL_ListModes&nbsp;--&nbsp;Returns a pointer to an array of available screen dimensions for 
the given format and video flags</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN779"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN780"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_Rect **<B
CLASS="FSFUNC"
>SDL_ListModes</B
></CODE
>(SDL_PixelFormat *format, Uint32 flags);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN786"
></A
><H2
>Description</H2
><P
>Return a pointer to an array of available screen dimensions for the given
format and video flags, sorted largest to smallest.  Returns
<TT
CLASS="LITERAL"
>NULL</TT
> if there are no dimensions available for a particular
format, or <SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if any dimension is okay for
the given format.</P
><P
>If <TT
CLASS="PARAMETER"
><I
>format</I
></TT
> is <TT
CLASS="LITERAL"
>NULL</TT
>, the mode list
will be for the format returned by <A
HREF="sdlgetvideoinfo.html"
>SDL_GetVideoInfo()</A
>-&#62;<TT
CLASS="STRUCTFIELD"
><I
>vfmt</I
></TT
>. The <TT
CLASS="PARAMETER"
><I
>flag</I
></TT
> parameter is an OR'd combination of <A
HREF="sdlsurface.html"
>surface</A
> flags. The flags are the same as those used <A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
> and they play a strong role in deciding what modes are valid. For instance, if you pass <TT
CLASS="LITERAL"
>SDL_HWSURFACE</TT
> as a flag only modes that support hardware video surfaces will be returned.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN801"
></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>SDL_Rect **modes;
int i;
.
.
.

/* Get available fullscreen/hardware modes */
modes=SDL_ListModes(NULL, SDL_FULLSCREEN|SDL_HWSURFACE);

/* Check is there are any modes available */
if(modes == (SDL_Rect **)0){
  printf("No modes available!\n");
  exit(-1);
}

/* Check if or resolution is restricted */
if(modes == (SDL_Rect **)-1){
  printf("All resolutions available.\n");
}
else{
  /* Print valid modes */
  printf("Available Modes\n");
  for(i=0;modes[i];++i)
    printf("  %d x %d\n", modes[i]-&#62;w, modes[i]-&#62;h);
}
.
.</PRE
></DIV
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><A
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><H2
>See Also</H2
><P
><A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>,
<A
HREF="sdlgetvideoinfo.html"
><TT
CLASS="FUNCTION"
>SDL_GetVideoInfo</TT
></A
>,
<A
HREF="sdlrect.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Rect</SPAN
></A
>,
<A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
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