Mercurial > sdl-ios-xcode
view include/SDL_version.h @ 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 | 453587d6dc87 |
children | 4c4113c2162c |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2009 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ /* This header defines the current SDL version */ #ifndef _SDL_version_h #define _SDL_version_h #include "SDL_stdinc.h" #include "begin_code.h" /* Set up for C function definitions, even when using C++ */ #ifdef __cplusplus extern "C" { #endif /* Printable format: "%d.%d.%d", MAJOR, MINOR, PATCHLEVEL */ #define SDL_MAJOR_VERSION 1 #define SDL_MINOR_VERSION 2 #define SDL_PATCHLEVEL 14 typedef struct SDL_version { Uint8 major; Uint8 minor; Uint8 patch; } SDL_version; /* This macro can be used to fill a version structure with the compile-time * version of the SDL library. */ #define SDL_VERSION(X) \ { \ (X)->major = SDL_MAJOR_VERSION; \ (X)->minor = SDL_MINOR_VERSION; \ (X)->patch = SDL_PATCHLEVEL; \ } /* This macro turns the version numbers into a numeric value: (1,2,3) -> (1203) This assumes that there will never be more than 100 patchlevels */ #define SDL_VERSIONNUM(X, Y, Z) \ ((X)*1000 + (Y)*100 + (Z)) /* This is the version number macro for the current SDL version */ #define SDL_COMPILEDVERSION \ SDL_VERSIONNUM(SDL_MAJOR_VERSION, SDL_MINOR_VERSION, SDL_PATCHLEVEL) /* This macro will evaluate to true if compiled with SDL at least X.Y.Z */ #define SDL_VERSION_ATLEAST(X, Y, Z) \ (SDL_COMPILEDVERSION >= SDL_VERSIONNUM(X, Y, Z)) /* This function gets the version of the dynamically linked SDL library. it should NOT be used to fill a version structure, instead you should use the SDL_Version() macro. */ extern DECLSPEC const SDL_version * SDLCALL SDL_Linked_Version(void); /* Ends C function definitions when using C++ */ #ifdef __cplusplus } #endif #include "close_code.h" #endif /* _SDL_version_h */