Mercurial > sdl-ios-xcode
view docs/html/guideaudioexamples.html @ 4106:12bb6311fd5d SDL-1.2
Hans de Goede fixed bug #495
When running boswars: http://www.boswars.org/ on a machine with intel
integrathed graphics it crashes when it tries to play the initial theora
splashscreen video:
X Error of failed request: BadAlloc (insufficient resources for operation)
Major opcode of failed request: 140 (XVideo)
Minor opcode of failed request: 19 ()
Serial number of failed request: 25
Current serial number in output stream: 26
boswars: xcb_xlib.c:41: xcb_xlib_lock: Assertion `!c->xlib.lock' failed.
Aborted
I recognized this problem from a few years back, when I encountered it while
working on the Xv blitter for xmame. The problem is that for some reason
creation the Xvport and XvImage succeeds, and failure (lack of resources / hw
capability?) is only indicated during the first XvPut[Shm]Image. I've written a
patch for SDL using the work around for this I developed for xmame (and which
is still used successfully in xmame after many years of usage).
I'll admit it isn't very pretty, but after investigating several possibilities
this was the best option, any other fixes would need changes to the SDL api and
abi.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 29 Dec 2007 02:23:48 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >Audio Examples</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Examples" HREF="guideexamples.html"><LINK REL="PREVIOUS" TITLE="Event Examples" HREF="guideeventexamples.html"><LINK REL="NEXT" TITLE="CDROM Examples" HREF="guidecdromexamples.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="guideeventexamples.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 4. Examples</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="guidecdromexamples.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="GUIDEAUDIOEXAMPLES" ></A >Audio Examples</H1 ><P ></P ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN382" ></A >Opening the audio device</H2 ><P ><PRE CLASS="PROGRAMLISTING" > SDL_AudioSpec wanted; extern void fill_audio(void *udata, Uint8 *stream, int len); /* Set the audio format */ wanted.freq = 22050; wanted.format = AUDIO_S16; wanted.channels = 2; /* 1 = mono, 2 = stereo */ wanted.samples = 1024; /* Good low-latency value for callback */ wanted.callback = fill_audio; wanted.userdata = NULL; /* Open the audio device, forcing the desired format */ if ( SDL_OpenAudio(&wanted, NULL) < 0 ) { fprintf(stderr, "Couldn't open audio: %s\n", SDL_GetError()); return(-1); } return(0);</PRE ></P ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN386" ></A >Playing audio</H2 ><P ><PRE CLASS="PROGRAMLISTING" > static Uint8 *audio_chunk; static Uint32 audio_len; static Uint8 *audio_pos; /* The audio function callback takes the following parameters: stream: A pointer to the audio buffer to be filled len: The length (in bytes) of the audio buffer */ void fill_audio(void *udata, Uint8 *stream, int len) { /* Only play if we have data left */ if ( audio_len == 0 ) return; /* Mix as much data as possible */ len = ( len > audio_len ? audio_len : len ); SDL_MixAudio(stream, audio_pos, len, SDL_MIX_MAXVOLUME); audio_pos += len; audio_len -= len; } /* Load the audio data ... */ ;;;;; audio_pos = audio_chunk; /* Let the callback function play the audio chunk */ SDL_PauseAudio(0); /* Do some processing */ ;;;;; /* Wait for sound to complete */ while ( audio_len > 0 ) { SDL_Delay(100); /* Sleep 1/10 second */ } SDL_CloseAudio();</PRE ></P ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="guideeventexamples.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="guidecdromexamples.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Event Examples</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="guideexamples.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >CDROM Examples</TD ></TR ></TABLE ></DIV ></BODY ></HTML >