Sat, 21 Aug 2004 13:49:22 +0000*** empty log message ***
Sam Lantinga <> [Sat, 21 Aug 2004 13:49:22 +0000] rev 945
*** empty log message ***

Sat, 21 Aug 2004 13:10:58 +0000Date: Wed, 28 Jul 2004 14:56:57 +0800
Sam Lantinga <> [Sat, 21 Aug 2004 13:10:58 +0000] rev 944
Date: Wed, 28 Jul 2004 14:56:57 +0800
From: Aaron Perez
Subject: [SDL] Fwd: SDL not checking malloc returning NULL

I was reading through the code and i found that in several places does a
malloc and without checking if it is NULL just use the pointer.

Sat, 21 Aug 2004 12:38:50 +0000Date: Sun, 18 Jul 2004 00:22:07 -0400
Sam Lantinga <> [Sat, 21 Aug 2004 12:38:50 +0000] rev 943
Date: Sun, 18 Jul 2004 00:22:07 -0400
From: "Philippe Anctil"
Subject: [SDL] odd mouse event generated on init

The mouse relative and absolute coordinates appear to be always equal for
the first mouse event.

Sat, 21 Aug 2004 12:27:02 +0000Here are patches for SDL12 and SDL_mixer for 4 or 6 channel
Sam Lantinga <> [Sat, 21 Aug 2004 12:27:02 +0000] rev 942
Here are patches for SDL12 and SDL_mixer for 4 or 6 channel
surround sound on Linux using the Alsa driver. To use them, naturally
you need a sound card that will do 4 or 6 channels and probably also a
recent version of the Alsa drivers and library. Since the only SDL
output driver that knows about surround sound is the Alsa driver,
you���ll want to choose it, using:


There are no syntactic changes to the programming API. No new
library calls, no differences in arguments.

There are two semantic changes:

(1) For library calls with number of channels as an argument, formerly
you could use only 1 or 2 for the number of channels. Now you
can also use 4 or 6.

(2) The two "left" and "right" arguments to Mix_SetPanning, for the
case of 4 or 6 channels, no longer simply control the volumes of
the left and right channels. Now the "left" argument is converted
to an angle and Mix_SetPosition is called, and the "right" argu-
ment is ignored.

With two exceptions, so far as I know, the modified SDL12 and
SDL_mixer work the same way as the original versions, when opened for
1 or 2 channel output. The two exceptions are bugs which I fixed.
Well, the first, anyway, is a bug for sure. When rate conversions up
or down by a factor of two are applied (in src/audio/SDL_audiocvt.c),
streams with different numbers of channels (that is, mono and stereo)
are treated the same way: either each sample is copied or every other
sample is omitted. This is ok for mono, but for stereo, it is frames
that should be copied or omitted, where by "frame" I mean a portion of
the stream containing one sample for each channel. (In the SDL source,
confusingly, sometimes frames are called "samples".) So for these
rate conversions, stereo streams have to be treated differently, and
they are, in my modified version.

The other problem that might be characterized as a bug arises
when SDL_mixer is passed a multichannel chunk which does not have an
integral number of frames. Due to the way the effect_position code
loops over frames, when the chunk ends with a partial frame, memory
outside the chunk buffer will be accessed. In the case of stereo,
it���s possible that because malloc may give more memory than requested,
this potential problem never actually causes a segment fault. I don���t
know. For 6 channel chunks, I do know, and it does cause segment

If SDL_mixer is passed defective chunks and this causes a segment
fault, arguably, that���s not a bug in SDL_mixer. Still, whether or not
it counts as a bug, it���s easy to protect against, so why not? I added
code in mixer.c to discard any partial frame at the end of a chunk.

Then what about when SDL or SDL_mixer is opened for 4 or 6 chan-
nel output? What happens with the parts of the current library
designed for stereo? I don���t know whether I���ve covered all the bases,
but I���ve tried:

(1) For playing 2 channel waves, or other cases where SDL knows it has
to match up a 2 channel source with a 4 or 6 channel output, I���ve
added code in SDL_audiocvt.c to make the necessary conversions.

(2) For playing midis using timidity, I���ve converted timidity to do 4
or 6 channel output, upon request.

(3) For playing mods using mikmod, I put ad hoc code in music.c to
convert the stereo output that mikmod produces to 4 or 6 chan-
nels. Obviously it would be better to change the mikmod code to
mix down into 4 or 6 channels, but I have a hard time following
the code in mikmod, so I didn���t do that.

(4) For playing mp3s, I put ad hoc code in smpeg to copy channels in
the case when 4 or 6 channel output is needed.

(5) There seems to be no problem with .ogg files - stereo .oggs can be
up converted as .wavs are.

(6) The effect_position code in SDL_mixer is now generalized to in-
clude the cases of 4 and 6 channel streams.

I���ve done a very limited amount of compatibility testing for some
of the games using SDL I happen to have. For details, see the file

I���ve put into a separate archive, Surround-SDL-testfiles.tgz, a
couple of 6 channel wave files for testing and a 6 channel ogg file.
If you have the right hardware and version of Alsa, you should be able
to play the wave files with the Alsa utility aplay (and hear all
channels, except maybe lfe, for chan-id.wav, since it���s rather faint).
Don���t expect aplay to give good sound, though. There���s something
wrong with the current version of aplay.

The canyon.ogg file is to test loading of 6 channel oggs. After
patching and compiling, you can play it with playmus. (My version of
ogg123 will not play it, and I had to patch mplayer to get it to play
6 channel oggs.)

Greg Lee <>
Thus, July 1, 2004

Sat, 21 Aug 2004 11:34:24 +0000Date: Mon, 12 Jul 2004 14:17:47 -0500
Sam Lantinga <> [Sat, 21 Aug 2004 11:34:24 +0000] rev 941
Date: Mon, 12 Jul 2004 14:17:47 -0500
From: Richard Smith
Subject: Re: [SDL] Disableing color depth and mode searching

> Also, I should add that a quick way to get the desired effect is to
> #define BROKEN_MODES on top of the SDL_fbvideo.c file.

Ah yes, I see that looks like that will do what I need. Curious as to
why this is a #define and not an enviroment variable like the other

I would think that finding cards (or chips) with broken modes would be
the norm rather than the execption.

Sat, 21 Aug 2004 05:29:45 +0000Date: Sat, 10 Jul 2004 21:02:33 +0200
Sam Lantinga <> [Sat, 21 Aug 2004 05:29:45 +0000] rev 940
Date: Sat, 10 Jul 2004 21:02:33 +0200
From: "Philippe Plantier (ayin)"
Subject: [SDL] Problems allocating large surfaces

There are problems when allocating large surfaces using SDL_CreateRGBSurface.

When, for example, we try to allocate a surface wider than 16384 pixels,
the calculation of the pitch overflows; this leads to a surface that
has the w and h flags correctly set, but whose "pixels" buffer is too
small. That may lead to heap corruption.

Sat, 21 Aug 2004 04:20:00 +0000Date: Tue, 01 Jun 2004 15:27:44 +0300
Sam Lantinga <> [Sat, 21 Aug 2004 04:20:00 +0000] rev 939
Date: Tue, 01 Jun 2004 15:27:44 +0300
From: Martin_Storsj
Subject: Update for dynamic loading of ALSA

I sent you a patch a few months ago which enables SDL to load ALSA
dynamically. Now I've finally got time to tweak this yet some more. I've
added code from alsa.m4 (from alsa's dev package) to acinclude.m4, and
made the detection of the alsa library name a bit better. I've also
fixed up the loading versioned symbols with dlvsym, so that it falls
back to dlsym.

I wouldn't say the configure script is complete yet, but this is how far
I've come this time, and I'm no expert at those things.

Sat, 21 Aug 2004 03:55:12 +0000Hmm, this should work a little better. :)
Sam Lantinga <> [Sat, 21 Aug 2004 03:55:12 +0000] rev 938
Hmm, this should work a little better. :)

Sat, 21 Aug 2004 03:45:58 +0000Date: Tue, 27 Jul 2004 17:14:00 +0200
Sam Lantinga <> [Sat, 21 Aug 2004 03:45:58 +0000] rev 937
Date: Tue, 27 Jul 2004 17:14:00 +0200
From: "Eckhard Stolberg"
Subject: Controller names in SDL for Windows

I'm working on an Atari 2600 emulator for different systems that uses
the SDL. Some time ago someone created an adaptor that lets you use
your old Atari controllers with your computer through the USB port.
Some of the Atari controllers require special handling by the emulator,
so it would be nice, if it would be possible to detect if any of the
controllers connected to the computer is this adaptor.

SDL would allow that with the SDL_JoystickName function, but unfortunately
it doesn't work properly on Windows. On Linux and MacOSX this function
returns the name of the controller, but on Windows you'll only get the
name of the joystick driver. Most joysticks nowadays use the generic
Microsoft driver, so they all return the same name.

In an old MSDN article
Microsoft describes how to read out the OEM controller names from the registry.
I have implemented this for the SDL controller handler on Windows,
and now reading the joystick name works properly there too.

Sat, 21 Aug 2004 03:21:44 +0000CoreAudio driver works on Mac OSX 10.1
Sam Lantinga <> [Sat, 21 Aug 2004 03:21:44 +0000] rev 936
CoreAudio driver works on Mac OSX 10.1