Mercurial > sdl-ios-xcode
view docs/html/sdlaudiospec.html @ 2842:97ba0be8b565
Date: Sat, 06 Dec 2008 15:27:00 +0100
From: Couriersud
Subject: SDL: Relative mouse movements
The patch below will reenable processing of relative mouse movements.
The DirectFB drivers generates those in "grabbed" mode. These ensure,
that even in fullscreen mode relative movements are reported. SDLMAME
depends on this for games with trackballs.
Looking at the code I ask myself whether relative movements should be
handled in the drivers (x11, directfb). Both x11 and directfb are able
to report relative movements. This would leave it to the driver to use
the most appropriate method for relative movements when at the border of
a fullscreen window or being "grabbed".
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 06 Dec 2008 17:50:50 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_AudioSpec</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="Audio" HREF="audio.html"><LINK REL="PREVIOUS" TITLE="Audio" HREF="audio.html"><LINK REL="NEXT" TITLE="SDL_OpenAudio" HREF="sdlopenaudio.html"></HEAD ><BODY CLASS="REFENTRY" 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="audio.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlopenaudio.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLAUDIOSPEC" ></A >SDL_AudioSpec</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN6507" ></A ><H2 >Name</H2 >SDL_AudioSpec -- Audio Specification Structure</DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6510" ></A ><H2 >Structure Definition</H2 ><PRE CLASS="PROGRAMLISTING" >typedef struct{ int freq; Uint16 format; Uint8 channels; Uint8 silence; Uint16 samples; Uint32 size; void (*callback)(void *userdata, Uint8 *stream, int len); void *userdata; } SDL_AudioSpec;</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6513" ></A ><H2 >Structure Data</H2 ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN6515" ></A ><P ></P ><TABLE BORDER="0" CLASS="CALSTABLE" ><TBODY ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >freq</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Audio frequency in samples per second</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >format</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Audio data format</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >channels</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Number of channels: 1 mono, 2 stereo</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >silence</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Audio buffer silence value (calculated)</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >samples</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Audio buffer size in samples</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >size</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Audio buffer size in bytes (calculated)</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >callback(..)</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Callback function for filling the audio buffer</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >userdata</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >Pointer the user data which is passed to the callback function</TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6550" ></A ><H2 >Description</H2 ><P >The <SPAN CLASS="STRUCTNAME" >SDL_AudioSpec</SPAN > structure is used to describe the format of some audio data. This structure is used by <A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio</TT ></A > and <A HREF="sdlloadwav.html" ><TT CLASS="FUNCTION" >SDL_LoadWAV</TT ></A >. While all fields are used by <TT CLASS="FUNCTION" >SDL_OpenAudio</TT > only <TT CLASS="STRUCTFIELD" ><I >freq</I ></TT >, <TT CLASS="STRUCTFIELD" ><I >format</I ></TT >, <TT CLASS="STRUCTFIELD" ><I >samples</I ></TT > and <TT CLASS="STRUCTFIELD" ><I >channels</I ></TT > are used by <TT CLASS="FUNCTION" >SDL_LoadWAV</TT >. We will detail these common members here.</P ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN6564" ></A ><P ></P ><TABLE BORDER="0" CLASS="CALSTABLE" ><TBODY ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >freq</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><P >The number of samples sent to the sound device every second. Common values are 11025, 22050 and 44100. The higher the better.</P ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >format</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><P >Specifies the size and type of each sample element <P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="LITERAL" >AUDIO_U8</TT ></DT ><DD ><P >Unsigned 8-bit samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_S8</TT ></DT ><DD ><P >Signed 8-bit samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_U16</TT > or <TT CLASS="LITERAL" >AUDIO_U16LSB</TT ></DT ><DD ><P >Unsigned 16-bit little-endian samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_S16</TT > or <TT CLASS="LITERAL" >AUDIO_S16LSB</TT ></DT ><DD ><P >Signed 16-bit little-endian samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_U16MSB</TT ></DT ><DD ><P >Unsigned 16-bit big-endian samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_S16MSB</TT ></DT ><DD ><P >Signed 16-bit big-endian samples</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_U16SYS</TT ></DT ><DD ><P >Either <TT CLASS="LITERAL" >AUDIO_U16LSB</TT > or <TT CLASS="LITERAL" >AUDIO_U16MSB</TT > depending on you systems endianness</P ></DD ><DT ><TT CLASS="LITERAL" >AUDIO_S16SYS</TT ></DT ><DD ><P >Either <TT CLASS="LITERAL" >AUDIO_S16LSB</TT > or <TT CLASS="LITERAL" >AUDIO_S16MSB</TT > depending on you systems endianness</P ></DD ></DL ></DIV ></P ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >channels</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >The number of seperate sound channels. 1 is mono (single channel), 2 is stereo (dual channel).</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >samples</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >When used with <A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio</TT ></A > this refers to the size of the audio buffer in samples. A sample a chunk of audio data of the size specified in <TT CLASS="PARAMETER" ><I >format</I ></TT > mulitplied by the number of channels. When the <SPAN CLASS="STRUCTNAME" >SDL_AudioSpec</SPAN > is used with <A HREF="sdlloadwav.html" ><TT CLASS="FUNCTION" >SDL_LoadWAV</TT ></A > <TT CLASS="STRUCTFIELD" ><I >samples</I ></TT > is set to 4096.</TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6639" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio</TT ></A >, <A HREF="sdlloadwav.html" ><TT CLASS="FUNCTION" >SDL_LoadWAV</TT ></A ></P ></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="audio.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="sdlopenaudio.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Audio</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="audio.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_OpenAudio</TD ></TR ></TABLE ></DIV ></BODY ></HTML >