view docs/html/sdlcdopen.html @ 2042:3908e1f808e1

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 15:56:36 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_CDOpen</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
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><H1
><A
NAME="SDLCDOPEN"
></A
>SDL_CDOpen</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN7274"
></A
><H2
>Name</H2
>SDL_CDOpen&nbsp;--&nbsp;Opens a CD-ROM drive for access.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN7277"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN7278"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_CD *<B
CLASS="FSFUNC"
>SDL_CDOpen</B
></CODE
>(int drive);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7284"
></A
><H2
>Description</H2
><P
>Opens a CD-ROM drive for access.  It returns a <A
HREF="sdlcd.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_CD</SPAN
></A
> structure on success, or <TT
CLASS="LITERAL"
>NULL</TT
> if the drive was invalid or busy.  This newly opened CD-ROM becomes the default CD used when other CD functions are passed a <TT
CLASS="LITERAL"
>NULL</TT
> CD-ROM handle. </P
><P
>Drives are numbered starting with 0.  
Drive 0 is the system default CD-ROM.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN7292"
></A
><H2
>Examples</H2
><PRE
CLASS="PROGRAMLISTING"
>SDL_CD *cdrom;
int cur_track;
int min, sec, frame;
SDL_Init(SDL_INIT_CDROM);
atexit(SDL_Quit);

/* Check for CD drives */
if(!SDL_CDNumDrives()){
  /* None found */
  fprintf(stderr, "No CDROM devices available\n");
  exit(-1);
}

/* Open the default drive */
cdrom=SDL_CDOpen(0);

/* Did if open? Check if cdrom is NULL */
if(!cdrom){
  fprintf(stderr, "Couldn't open drive: %s\n", SDL_GetError());
  exit(-1);
}

/* Print Volume info */
printf("Name: %s\n", SDL_CDName(0));
printf("Tracks: %d\n", cdrom-&#62;numtracks);
for(cur_track=0;cur_track &#60; cdrom-&#62;numtracks; cur_track++){
  FRAMES_TO_MSF(cdrom-&#62;track[cur_track].length, &#38;min, &#38;sec, &#38;frame);
  printf("\tTrack %d: Length %d:%d\n", cur_track, min, sec);
}

SDL_CDClose(cdrom);</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlcd.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_CD</SPAN
></A
>,
<A
HREF="sdlcdtrack.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_CDtrack</SPAN
></A
>,
<A
HREF="sdlcdclose.html"
><TT
CLASS="FUNCTION"
>SDL_CDClose</TT
></A
></P
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