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Date: Mon, 02 May 2005 04:23:16 -0500 From: Jonathan Atkins Subject: Re: [PATCH] *CRITICAL* 8bit direct RGB palette not being created I think that SDL_AllocFormat should create the palette for all 8bit surfaces. And when the RGBAmasks match the normal 3:3:2:0 we need to apply the old behavior. If the mask doesn't match that, then we need to make the right palette assuming the masks are valid (I don't think we validate any masks for high color surfaces...so we wouldn't here) Then there's always a palette available for the 8bit surfaces. This restores the normal behavior and allows for masks to create palettes automatically for odd masks even, which would be a neato thing to have in there, as SDL never did this before.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 16 May 2005 05:34:58 +0000
parents e5bc29de3f0a
children 546f7c1eb755
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.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