Mercurial > sdl-ios-xcode
view docs/index.html @ 4216:5b99971a27b4 SDL-1.2
Fixed bug #698
Hans de Goede 2009-02-13 01:10:52 PST
Since the new "glitch free" version of pulseaudio (used in Fedora 10 amongst
others), the sound of SDL using apps (like a simple playmus call) has been
crackling.
While looking in to fixing this I noticed that the current pulseaudio code in
SDL uses pa_simple. However pa_simple uses a thread to pump pulseaudio events
and ipc, given that SDL already has its own thread for audio handling this is
clearly suboptimal, leading to unnecessary context switching IPC, etc. Also
pa_simple does not allow one to implement the WaitAudio() callback for SDL
audiodrivers properly.
Given that my work is mostly a rewrite (although some original pieces remain)
I'm attaching the new .c and .h file, as that is easier to review then the huge
diff.
Let me know if you also want the diff.
This new version has the following features:
-no longer use an additional thread next to the SDL sound thread
-do not crackle with glitch free audio
-when used with a newer pulse, which does glitch free audio, the total latency
is
the same as with the alsa driver
-proper WaitAudio() implementation, saving another mixlen worth of latency
-adds a WaitDone() implementation
This patch has been written in consultancy with Lennart Poetering (the
pulseaudio author) and has been reviewed by him for correct use of the pa API.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 21 Sep 2009 09:27:08 +0000 |
parents | c6a447c98584 |
children |
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<!DOCTYPE HTML PUBLIC "-//Norman Walsh//DTD DocBook HTML 1.0//EN"> <HTML> <HEAD><TITLE>Simple DirectMedia Layer Introduction</TITLE></HEAD> <BODY BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000"> <DIV CLASS="NAVHEADER"> <HR ALIGN="LEFT" WIDTH="100%"> </DIV> <DIV CLASS="PREFACE"> <H2><A NAME="AEN8">Simple DirectMedia Layer Introduction</A></H2> <P> This library is designed to make it easy to write games that run on many different platforms using the various native high-performance media interfaces, (for video, audio, etc) and presenting a single source-code level API to your application. This is a fairly low level API, but using this, completely portable applications can be written with a great deal of flexibility. </P><P> An introduction to SDL can be found online at: <A HREF="http://www.libsdl.org/intro.php" TARGET="_top"> http://www.libsdl.org/intro.php</A> </P><P> Tutorials on a variety of topics can be found online at: <A HREF="http://www.libsdl.org/tutorials.php" TARGET="_top"> http://www.libsdl.org/tutorials.php</A> </P><P> Documentation in Wiki form can be found online at: <A HREF="http://www.libsdl.org/cgi/docwiki.cgi/" TARGET="_top"> http://www.libsdl.org/cgi/docwiki.cgi/</A> </P><P> Enjoy! </P><P> Sam Lantinga <TT CLASS="EMAIL"><<A HREF="mailto:slouken@libsdl.org"><A HREF="mailto:slouken@libsdl.org" TARGET="_top" >slouken@libsdl.org</A></A>></TT> </P> <P> <br><br><HR> <H1>Table of Contents</H1> <UL> <LI><A HREF="html/index.html">Full Table of Contents</A></LI> <LI><A HREF="html/guide.html">The SDL Guide</A></LI> <LI><A HREF="html/reference.html">The SDL Reference</A></LI> <UL> <LI><A HREF="html/general.html">Initialization</A></LI> <LI><A HREF="html/video.html">Video</A></LI> <LI><A HREF="html/wm.html">Window Manager</A></LI> <LI><A HREF="html/event.html">Event Handling</A></LI> <LI><A HREF="html/joystick.html">Joystick</A></LI> <LI><A HREF="html/audio.html">Audio</A></LI> <LI><A HREF="html/cdrom.html">CDROM</A></LI> <LI><A HREF="html/thread.html">Threads</A></LI> <LI><A HREF="html/time.html">Timers</A></LI> </UL> </UL> </DIV ></BODY ></HTML >