view docs/html/sdlvideoinfo.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="SDLVIDEOINFO"
>SDL_VideoInfo</A
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><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN3006"
></A
><H2
>Name</H2
>SDL_VideoInfo&nbsp;--&nbsp;Video Target information</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3009"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  Uint32 hw_available:1;
  Uint32 wm_available:1;
  Uint32 blit_hw:1;
  Uint32 blit_hw_CC:1;
  Uint32 blit_hw_A:1;
  Uint32 blit_sw:1;
  Uint32 blit_sw_CC:1;
  Uint32 blit_sw_A:1;
  Uint32 blit_fill;
  Uint32 video_mem;
  SDL_PixelFormat *vfmt;
} SDL_VideoInfo;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3012"
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><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
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><TT
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><I
>hw_available</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Is it possible to create hardware surfaces?</TD
></TR
><TR
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><TT
CLASS="STRUCTFIELD"
><I
>wm_available</I
></TT
></TD
><TD
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>Is there a window manager available</TD
></TR
><TR
><TD
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><TT
CLASS="STRUCTFIELD"
><I
>blit_hw</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Are hardware to hardware blits accelerated?</TD
></TR
><TR
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ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>blit_hw_CC</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Are hardware to hardware colorkey blits accelerated?</TD
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><TR
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><TT
CLASS="STRUCTFIELD"
><I
>blit_hw_A</I
></TT
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><TD
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>Are hardware to hardware alpha blits accelerated?</TD
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><TT
CLASS="STRUCTFIELD"
><I
>blit_sw</I
></TT
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><TD
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>Are software to hardware blits accelerated?</TD
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><TT
CLASS="STRUCTFIELD"
><I
>blit_sw_CC</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Are software to hardware colorkey blits accelerated?</TD
></TR
><TR
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ALIGN="LEFT"
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><TT
CLASS="STRUCTFIELD"
><I
>blit_sw_A</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Are software to hardware alpha blits accelerated?</TD
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><TT
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><I
>blit_fill</I
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>Are color fills accelerated?</TD
></TR
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><TT
CLASS="STRUCTFIELD"
><I
>video_mem</I
></TT
></TD
><TD
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>Total amount of video memory in Kilobytes</TD
></TR
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><TT
CLASS="STRUCTFIELD"
><I
>vfmt</I
></TT
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><A
HREF="sdlpixelformat.html"
>Pixel format</A
> of the video device</TD
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><A
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></A
><H2
>Description</H2
><P
>This (read-only) structure is returned by <A
HREF="sdlgetvideoinfo.html"
><TT
CLASS="FUNCTION"
>SDL_GetVideoInfo</TT
></A
>. It contains information on either the 'best' available mode  (if called before <A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>) or the current video mode.</P
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><H2
>See Also</H2
><P
><A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
>,
<A
HREF="sdlgetvideoinfo.html"
><TT
CLASS="FUNCTION"
>SDL_GetVideoInfo</TT
></A
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