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view docs/man3/SDL_CreateRGBSurfaceFrom.3 @ 773:da0a2ad35bf4
Date: Sun, 4 Jan 2004 23:48:19 +0100
From: Max Horn
Subject: Re: Again Audio CD patch
Am 04.01.2004 um 22:38 schrieb Sam Lantinga:
>
> Okay, I fixed the buffering problems by simply using a 4 second buffer
> instead of a 1 second buffer. However, using your code I can't play an
> entire CD - the playback stops after the first song.
>
Found the problem: FSReadFork returns eofErr when the file is finished.
However, we check its return value for errors, and if anything but
noErr occurs, the reader thread aborts its current iteration. That is
bad, because it aborts before it can ever set the flag which tells that
the file is over (also, any remaining data which FSRead did return is
lost - so you'd not hear about to 4 seconds from the end of the file.
Furthermore, the computed data size was 8 bytes to high (I forgot to
account for the fact that the size of an (A)IFF chunk always contains
the chunk header & size fields, too). This is enough to make it work.
However, the end condition is rather fragile, so I tuned some other
things to be pessimistic (check for <= 0 instead of == 0, when eofErr
is encountered enforce mReadFilePosition == mFileLength). You never
know...
The attached patch fixes the issue for me.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 05 Jan 2004 00:57:51 +0000 |
parents | e5bc29de3f0a |
children | 546f7c1eb755 |
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.TH "SDL_CreateRGBSurfaceFrom" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" .SH "NAME" SDL_CreateRGBSurfaceFrom\- Create an SDL_Surface from pixel data .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBSDL_Surface *\fBSDL_CreateRGBSurfaceFrom\fP\fR(\fBvoid *pixels, int width, int height, int depth, int pitch, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask\fR); .SH "DESCRIPTION" .PP Creates an SDL_Surface from the provided pixel data\&. .PP The data stored in \fBpixels\fR is assumed to be of the \fBdepth\fR specified in the parameter list\&. The pixel data is not copied into the \fBSDL_Surface\fR structure so it should not be freed until the surface has been freed with a called to \fISDL_FreeSurface\fR\&. \fBpitch\fR is the length of each scanline in bytes\&. .PP See \fI\fBSDL_CreateRGBSurface\fP\fR for a more detailed description of the other parameters\&. .SH "RETURN VALUE" .PP Returns the created surface, or \fBNULL\fR upon error\&. .SH "SEE ALSO" .PP \fI\fBSDL_CreateRGBSurface\fP\fR, \fI\fBSDL_FreeSurface\fP\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01