view docs/man3/SDL_CD.3 @ 3880:74e828c64315 SDL-1.2

Fixed bug #292 I might be on crack here. It looks like SDL_ConvertMono() in src/audio/SDL_audiocvt.c adds the left and right channels of a stereo stream together, and clamps the new mono channel if it would overflow. Shouldn't it be dividing by 2 to average the two sample points instead of clamping? Otherwise the mono sample point's volume doubles in the conversion. This would also make the conversion faster, as it replaces two branches per sample frame with a bitwise shift. --ryan.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 15:45:37 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_CD" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_CD\- CDROM Drive Information
.SH "STRUCTURE DEFINITION"
.PP
.nf
\f(CWtypedef struct{
  int id;
  CDstatus status;
  int numtracks;
  int cur_track;
  int cur_frame;
  SDL_CDtrack track[SDL_MAX_TRACKS+1];
} SDL_CD;\fR
.fi
.PP
.SH "STRUCTURE DATA"
.TP 20
\fBid\fR
Private drive identifier
.TP 20
\fBstatus\fR
Drive \fIstatus\fR
.TP 20
\fBnumtracks\fR
Number of tracks on the CD
.TP 20
\fBcur_track\fR
Current track
.TP 20
\fBcur_frame\fR
Current frame offset within the track
.TP 20
\fBtrack\fR[SDL_MAX_TRACKS+1]
Array of track descriptions\&. (see \fI\fBSDL_CDtrack\fR\fR)
.SH "DESCRIPTION"
.PP
An \fBSDL_CD\fR structure is returned by \fI\fBSDL_CDOpen\fP\fR\&. It represents an opened CDROM device and stores information on the layout of the tracks on the disc\&.
.PP
A frame is the base data unit of a CD\&. \fBCD_FPS\fP frames is equal to 1 second of music\&. SDL provides two macros for converting between time and frames: \fBFRAMES_TO_MSF(f, M,S,F)\fP and \fBMSF_TO_FRAMES\fP\&.
.SH "EXAMPLES"
.PP
.nf
\f(CWint min, sec, frame;
int frame_offset;

FRAMES_TO_MSF(cdrom->cur_frame, &min, &sec, &frame);
printf("Current Position: %d minutes, %d seconds, %d frames
", min, sec, frame);

frame_offset=MSF_TO_FRAMES(min, sec, frame);\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_CDOpen\fP\fR, \fI\fBSDL_CDtrack\fR\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58