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------- Comment #1 From Max Horn 2006-04-17 03:08 [reply] ------- Created an attachment (id=106) [edit] Patch for src/joystick/win32/SDL_mmjoystick.c I am not even a Windows user, so take the following with a grain of salt: SDL_mmjoystick.c has a function GetJoystickName which obtains the joystick name by looking at the registry. The way it does that seems very fishy to me. Namely, it uses the parameter "index" to construct a registry value name (BTW, those variables used in the code are really badly named). The value of "index" in turn equals the current value of "numdevs", as called from SDL_SYS_JoystickInit. I read through the MSDN docs at <http://msdn.microsoft.com/archive/default.asp?url=/archive/en-us/dnarinput/html/msdn_extdirect.asp>, and I believe the simple fix is to replace line 183 of said file SYS_JoystickName[numdevs] = GetJoystickName(numdevs, joycaps.szRegKey); by the following: SYS_JoystickName[numdevs] = GetJoystickName(SYS_JoystickID[i], joycaps.szRegKey); However, that is only *hiding* the real issue. Problem is, the list of joysticks as returned by windows may contains "gaps", and the code deals incorrectly with that. Namely those gaps occur if joysticks are removed/(re)added, as the reporter observed. The attached patch fixes this and another (off-by-one) issue in the code. But since I have no Windows machine, I can't even test-compile it, so use with caution.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 29 Apr 2006 20:22:31 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_AudioSpec" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_AudioSpec\- Audio Specification Structure
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef 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;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBfreq\fR
Audio frequency in samples per second
.TP 20
\fBformat\fR
Audio data format
.TP 20
\fBchannels\fR
Number of channels: 1 mono, 2 stereo
.TP 20
\fBsilence\fR
Audio buffer silence value (calculated)
.TP 20
\fBsamples\fR
Audio buffer size in samples
.TP 20
\fBsize\fR
Audio buffer size in bytes (calculated)
.TP 20
\fBcallback(\&.\&.)\fR
Callback function for filling the audio buffer
.TP 20
\fBuserdata\fR
Pointer the user data which is passed to the callback function
.SH "DESCRIPTION"
.PP
The \fBSDL_AudioSpec\fR structure is used to describe the format of some audio data\&. This structure is used by \fI\fBSDL_OpenAudio\fP\fR and \fI\fBSDL_LoadWAV\fP\fR\&. While all fields are used by \fBSDL_OpenAudio\fP only \fBfreq\fR, \fBformat\fR, \fBsamples\fR and \fBchannels\fR are used by \fBSDL_LoadWAV\fP\&. We will detail these common members here\&.
.TP 20
\fBfreq\fR
The number of samples sent to the sound device every second\&. Common values are 11025, 22050 and 44100\&. The higher the better\&.
.TP 20
\fBformat\fR
Specifies the size and type of each sample element 
.IP "\fBAUDIO_U8\fP" 10Unsigned 8-bit samples
.IP "\fBAUDIO_S8\fP" 10Signed 8-bit samples
.IP "\fBAUDIO_U16\fP or \fBAUDIO_U16LSB\fP" 10Unsigned 16-bit little-endian samples
.IP "\fBAUDIO_S16\fP or \fBAUDIO_S16LSB\fP" 10Signed 16-bit little-endian samples
.IP "\fBAUDIO_U16MSB\fP" 10Unsigned 16-bit big-endian samples
.IP "\fBAUDIO_S16MSB\fP" 10Signed 16-bit big-endian samples
.IP "\fBAUDIO_U16SYS\fP" 10Either \fBAUDIO_U16LSB\fP or \fBAUDIO_U16MSB\fP depending on you systems endianness
.IP "\fBAUDIO_S16SYS\fP" 10Either \fBAUDIO_S16LSB\fP or \fBAUDIO_S16MSB\fP depending on you systems endianness
.TP 20
\fBchannels\fR
The number of seperate sound channels\&. 1 is mono (single channel), 2 is stereo (dual channel)\&.
.TP 20
\fBsamples\fR
When used with \fI\fBSDL_OpenAudio\fP\fR this refers to the size of the audio buffer in samples\&. A sample a chunk of audio data of the size specified in \fBformat\fR mulitplied by the number of channels\&. When the \fBSDL_AudioSpec\fR is used with \fI\fBSDL_LoadWAV\fP\fR \fBsamples\fR is set to 4096\&.
.SH "SEE ALSO"
.PP
\fI\fBSDL_OpenAudio\fP\fR, \fI\fBSDL_LoadWAV\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58