Mercurial > sdl-ios-xcode
view docs/man3/SDL_CD.3 @ 765:4c2ba6161939
Editors Note: The original patch was modified to use SDL_Delay() instead of
nanosleep because nanosleep may not be portable to all systems
using SDL with the ALSA backend. This may be a moot point with
the switch to blocking writes anyway...
Date: Sat, 27 Dec 2003 21:47:36 +0100
From: Michel Daenzer
To: Debian Bug Tracking System
Subject: [SDL] Bug#225252: [PATCH] ALSA fixes
Package: libsdl1.2debian-all
Version: 1.2.6-2
Severity: normal
Tags: patch
For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with
SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU
usage, interrupted sound and stuttering in some games here. Taking a nanosleep
whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more
efficient to use blocking mode for the actual sound playback. Feedback from the
SDL and ALSA lists appreciated.
The patch also fixes the default ALSA device to be used.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sun, 04 Jan 2004 15:40:50 +0000 |
| parents | e5bc29de3f0a |
| children | 546f7c1eb755 |
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.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