VGMTool Code

VGM input plugin 0.35
=====================

PROBLEMS
========

Here are the things that can go wrong, right at the start so you can 
find them easily.

1. VGM files play too fast

If you have in_gym then disable its VGM handling. It is weird.

2. Anything else

Please contact me!


Introduction
============

This is a Winamp (2.xx and 5.xx) plugin for playing VGM files. VGM is a
standard for frame-accurate logging of SN76489/SN76496 and various
YMxxxx writes, originated by Dave, allowing various systems' games'
music to be stored. See http://www.smspower.org/music for more
information, and to download VGM music files.

Open this URL in Winamp to hear a demo:

http://www.smspower.org/music/vgm/demo/Golvellius.m3u

To use: put in_vgm in Winamp's plugins\ folder, and restart Winamp. If 
you got the self-installing version then it should already be working.

Load .vgm or .vgz files in Winamp; go to the "File types" preferences
page to associate these extensions:

1. Open the Preferences dialogue box (press Ctrl+P, or right-click and
   choose Options -> Preferences...)
2. Choose "File types" from the tree on the left (it's the second item
   unless Winamp has changed since I wrote this)
3. Make sure "vgm" and "vgz" are selected in the "Associated extensions"
   list (if they aren't in the list it's because you have another buggy
   plugin installed)

Be sure to check out the file info and plugin configuration dialogues.

The YM2413 emulation engine is EMU2413 by Mitsutaka Okazaki 
(http://www.angel.ne.jp/~okazaki/ym2413). The PSG engine is by me. The 
YM2612 engine is from Gens by Stephane Dallongeville 
(http://gens.consolemul.com). The YM2151 engine is from MAME 
(http://www.mame.net) and was added by BlackAura. ZLib decompression
is by Jean-loup Gailly and Mark Adler.


Dialogue boxes
==============

1. VGM file & GD3 tag information

To open:
- In the main window, press Alt+3; or double-click on the track title;
  or right-click on the track title and choose "File info".
- In the playlist editor, select some files and press Alt+3; or right-
  click and choose "File info"; or press the "MISC" button, choose
  "FILE INF" and then "File info..."; or right-click the "MISC" button,
  choose " File info" and then "File info...".

This shows you information about the file and, if it has a GD3
information tag, it shows you information from there too. It's similar
to the ID3 information box for MP3s, except that you can't edit the GD3
tag from within Winamp.

Choose "English" or "Japanese" to display the GD3 information for that
language, if available.

If you see something like "????" for a GD3 entry then your version of
Windows doesn't support Unicode, or translation from Unicode to a valid
MBCS.

Click on "View GD3 in browser" to open either "Now Playing" (the
MiniBrowser in older versions of Winamp) or your regular web browser,
with a page showing the GD3 tag. The reason this is done is, HTML 4.0
compliant browsers *do* generally have the ability to display Unicode
text. You'll need to have appropriate fonts installed (Arial Unicode is 
a good one to have).

Click on "Configure plugin..." to open the plugin configuration
dialogue box.

If you open this dialogue box for several files in the playlist editor,
it will appear once for each file. Press Esc or press the [X] button to
abort showing it once per file.


2. VGM plugin configuration

To open:
- Open the "VGM file & GD3 tag information" dialogue box; then press the
  "Configure plugin..." button or press Alt+P.
- Or open the Winamp Preferences dialogue box (Right-click or menu
  button -> Options -> Preferences...; or press Ctrl+P), choose the
  Plug-ins -> Input page, then double-click on the "VGM input plugin
  v0.xx ( IN_VGM.DLL)" item, or select it and click on the Configure
  button.
  
Playback tab:

- Looping:
  "Repeat looped section x times"
    Choose how many times to play the looped section in a VGM file, if
    it has one. A value of 0 will play through the looped section once.
  "Then fade out over x ms"
    When repeating looped sections, there is no "end" to the music.
    Enter a time in ms (1000ms = 1s) over which the music will fade out
    after looping the desired number of times. A setting of 0 will give
    no fadeout.
  "Loop forever"
    Ignore the looping counter and loop forever. Note that this disables
    seeking (in Winamp) and thus also the "Immediate update" option.

- Pause after non-looped tracks
  "Pause x ms"
    Even when a track does have an end, it does not sound good if the
    next track follows on immediately. Enter a time in ms (1000ms = 1s)
    to pause at the end of each track.

- Playback rate:
  "Recorded rate"
    If this is selected, all VGM v1.01+ files will be played at the
    rate specified in the file. VGM 1.00 files will be played at 60Hz.
  "50Hz"
  "60Hz"
    If 50Hz or 60Hz is selected, all files will be played at that rate -
    50Hz corresponds to PAL/SECAM home systems used in Europe and
    Australia/NZ; 60Hz corresponds to NTSC/PAL-M systems used in Asia
    and the Americas.
  "Other: x Hz"
    If you choose this you can enter any rate, to play files extra
    slowly or quickly. Extreme values and fractional values are not
    allowed. Note that seeking is buggy with unusual rates.

  The effect will only be heard when you restart the track, or when the
  next track starts.

- Volume, muting and panning
  "Overdrive"
    Amplifies all sound to levels that are in danger of being clipped,
    but are similar to regular MP3s so visualisations work better.
  "Keep muting when track changes"
    If checked, per-muting will remain when the track changes; otherwise
    all channels are unmuted.
  "Randomise panning on track start"
    For chanels with configurable fake stereo, this will apply a
    Guassian randomisation to the stereo panning for every channel.

GD3 tags tab:

- Data formatting:
  "Prefer Japanese text"
    If checked, the media library and advanced title formatting will
    use Japanese text if available, otherwise English. If unchecked,
    English text is used in preference to Japanese.
  "Append (FM) to game name for YM2413"
    To make it easier to tell FM and PSG soundtracks apart, this will
    make the returned game name (given as the album name) end with
    "(FM)". Note that some emulators incorrectly specify an FM clock in
    the VGM file, causing this to be displayed wrongly.

- File Type:
  "Return file type ID"
    Winamp's Media Library comes by default with filtered views for
    "Audio" and "Video", as well as other views for htings like
    recently played files. If you right-click on the tree you can edit
    them and add new views for more advanced filters.

    If, like me, you don't want VGMs to play mixed in with your regular
    MP3s, you can use this to make it very easy to filter VGMs out of
    the "Audio" view and into another. Here's the procedure:

    1. Change the number to another value (I use 262144)
    2. Add a new view to the Media Library
    3. On the advanced tab, change the query to TYPE=262144 (or whatever
       number you chose)
    4. Refresh your Media Library from the Library button.

    Note that Winamp does not define meanings for values other than 0
    (audio) and 1 (video). It might in later versions, so try to use a
    value that is unlikely to be used in the future (2 is more likely
    to be used than 262144).

- Now Playing:
  "Display GD3 tags as HTML in "Now Playing""
    If checked, displaying a GD3 tag as HTML (using the "View GD3 in 
    browser" button described above) will use Now Playing. If unckecked, 
    it will use your regular web browser.
  "Display them automatically"
    If checked, GD3 tags will automatically be displayed in Now Playing
    when tracks start. This will also block most other parts of Winamp
    from changing the Now Playing page while a VGM file is playing.
  "Open "Now Playing" if it is closed"
    If checked, when auto-displaying GD3 tags, Now Playing will be
    opened if it is closed.
  Note that in older versions of Winamp, the MiniBrowser is the
  equivalent of Now Playing.

- Legacy title formatting
    Enter text to control what title Winamp shows for the file. Enter
    special codes like "%t" to insert various GD3 entries. If the file
    has no GD3 tag then the filename will be used as the title.
    Winamp 5's Advanced Title Formatting bypasses this, instead using
    data from the Media Library.

PSG tab:

- Chip control
  You can choose the relative volume of the chip (default: centre = 1.00)
  and globally enable/disable it.
  
- Channel control
  If the current track includes PSG data, the checkboxes will allow you
  to enable and disable indivisual sound channels.
  The trackbars allow you to apply "fake" stereo to the channels. This
  can result in a more pleasing sound but is totally inaccurate :) The
  original chip was strictly mono.
  That is, apart from the Game Gear's extended version which allows
  "digital" stereo (where the sound is either 100% left, centre or 100%
  right). If the track includes such data then the "fake" stereo for the
  affected channel is overridden.
  Press the "Centre all" button to reset all channels to a centre
  position.

- Emulation
  "Smooth PSG vol curve"
    Applies a smooth logarithmic volume curve to the PSG volume levels;
    if unchecked, values taken from a real SMS's output are used
    instead. These values have reduced definition at high volume levels.

YM2413 tab:

- Chip control
  You can choose the relative volume of the chip (default: centre = 1.00)
  and globally enable/disable it.

- Channel control
  If the current track includes PSG data, the checkbozes will allow you
  to enable and disable indivisual sound channels. You can also apply
  "fake" stereo as above.
  
- Emulation
  "High quality YM2413"
    This runs the YM2413 engine at the true clock rate and resamples to
    44100Hz. The effect is marginal.
    
YM2612/YM2151 tab:

- YM2612
  You can choose the relative volume of the chip (default: 0.25)
  and globally enable/disable it. You can also enable and disable
  individual channels. "Fake" stereo is unavailable because the YM2612
  supports real stereo.
  
- YM2151
  Relative volume and global enabling as above.


Bottom part of window:

"Immediate update"
  If this is selected, the effect of changing some of the settings will 
  be instant, but it may introduce jumps or pauses to the sound, 
  depending on the output plugin and the type of VGM file playing. If
  it is not selected then the effect will take the length of the output
  buffer (usually two seconds) to be heard.


Note that cancelling this dialogue box does *not* restore the previous
settings for many options.


Actually asked questions
========================

> y doesnt the winamp show vgms as associted files? i always have to
> select .vgm .vgz from the drop down menu.

This is a bug in old versions of Winamp, fixed in version 2.77. If your
Winamp is older you should update.

> FM music is not based on SINE waves, is it?!

Yes, it is. "Frequency modulation" means using one sine wave to change
the frequency of another, thereby producing quite complex waveforms
from two simple sine waves, a Good Thing when it comes to making cheap
sound chips. Although one source says "Note that the name 'FM' is a
misnomer; in actual fact the Yamaha chips all use phase modulation (PM)
to create their sounds." So now you know.

> The latest VGM plugin is much slower on my p133. The last one works
> fine, but with the new one the songs stops and then continues after a
> second all the time. Why?

Because FM emulation is a lot more complicated than PSG emulation, so
it takes more time. You might like to get VGMTool to optimise any VGMs
with unnecessary chip data in them, or possibly re-download the files
if they've been updated with optimised versions.


How to play VGM files direct from your webpage
==============================================

You can make it so people can click on a link and have a VGM played in
Winamp the same way as you can do it for MP3s...

1. Make a playlist file for the file(s) you want, listed as full URLs
2. Link to that

Winamp sets it up so IE will download and open the playlist without
prompting the user; the plugin then downloads the file itself and plays
it. I think Netscape does a similar thing, because most servers have
the MIME types properly set up for playlist files.


Known issues:
=============

You can choose to loop a VGM a lot of times. However, Winamp doesn't
like that...

- the playlist will either display the wrong track length or nothing,
  if it is over about 500 minutes
- some output plugins don't like it - eg. in Winamp 2.77, the waveOut
  plugin will display the wrong time while playing past 202:53
- very high values will make the main window/posbar length wrong too

On my computer, turning on the equaliser will make it use 3 times as
much CPU for PSG tunes, and 1.8 times as much for FM.

The equaliser does not process square waves well. I recommend you turn
it off if you can.

I tried a DSP plugin, "Dee". It crashes Winamp whenever you turn on the
3D thing, I have no idea why. So don't do that.

I tried another, "AlienDSP". It works quite well, and the "Pseudo
Stereo" is quite cool.

Fake stereo for SN76489 and YM2413 changes the apparent volume of the
channel being panned. I need to learn about panning laws and constant 
power output; I didn't do that yet. Please help me if you can!

History:
========

0.35 26/3/05
============

+ Fixed crash reading extended file info on files with no GD3 tag
+ Added per-chip enabling and preamplification controls
+ Settings saving is now updated for Winamp's user profile support
+ Added per-channel muting for YM2612
+ Added "loop forever" option
+ Improved HTML information display

0.34 7/12/05
============

+ Added high-pass filter for PCM to Gens sound core (by Blargg)
+ Pausing after non-looped tracks was broken in 0.33
+ This also broke skipping with short tracks
+ Fixed a couple of typos in the readme
+ Improved HTML information display

0.33 20/11/05
=============

+ Added support for YM2612 sample banks and VGM 1.50
+ Fixed some stupid old bugs with unlooped VGMs that nobody ever noticed
+ Updated ZLib to latest version
+ (Hopefully) removed dependency on MSVCRT*.DLL
+ Added file sniffer functionality so it will automagically play VGM
  files even if you change the extension (although that's not
  recommended)
+ Improved file info box chip usage display
+ Added tag caching for tag queries, to speed up media library tag
  retrieval
+ Changed to NSIS installer and packed in another demo VGM

0.32 30/10/05
=============

+ Added icons to config dialogue
+ Fixed issue with Now Playing loading information pages over the HTML
  information display
+ Added file length information into HTML information display
+ Updated downloader code to use Winamp's built-in downloader instead of
  using IE
+ Added msvcrt71.dll to installer
+ Enabled support for VGM 1.10
+ Re-integrated and extended Charles' MAME-style SMS Plus conversion of
  sn76489.c to hopefully make it more discoverable and re-usable by
  others
+ Added PSG panning support
+ Reorganised config interface
+ Added magical track number extraction for the Media Library by
  guessing the filename of the associated playlist file and finding
  which number entry it is in there - works well for most SMS Power
  releases, at least
+ Fixed Media Library year problems
+ Improved time formatting
+ Added YM2413 panning support
+ Added panning Gaussian randomisation
+ Improved emulation of non-Sega variant SN76489 for the Beeb fans

0.31 12/12/04
=============

+ Added Media Library extended title support and lots of associated
  options
+ And various other stuff too

0.30 28/5/03
============

+ Added pause between tracks and looping fadeout options
+ Updated to EMU2413 0.60: "Fixed HH&CYM generator and all voice datas."
+ Unupdated back to EMU2413 0.55 - percussion sounds terrible!
+ Added support for VGM v1.02 (custom PSG noise feedback)
+ Replaced MAME YM2612 core with Gens 2.10

0.29 31/10/02
=============

+ Added PSG noise boost option
+ Added PSG smooth volume curve option
+ Fixed bug in GD3 tag display

0.28 12/9/02
============

+ Configuration now uses a tabbed dialogue
+ Added WinXP "visual styles" support
+ Japanese text now shows under WinXP (hopefully)
+ Seeking bugs fixed
+ Cancelling the File Info dialogue box for a group of files now works
  properly
+ Improved mixing
+ Volume levels now match better for different chips
+ Fixed a typo which caused the YM2162 core not to be closed
+ Added some documentation to this file
+ Added a Help button which opens this file

0.27 1/5/02
===========

+ Fixed a bug with invalid GD3s
+ Updated to YM2413 0.55, which included a higher quality mode (12%
  higher sampling rate plus conversion). Use "High quality YM2413"
  checkbox to control it.
+ Modified PSG core to produce output similar to FM cores, ie. much
  quieter
+ Added Overdrive mode which amplifies the sound to levels similar to a
  typical MP3 file. It can cause clipping, though.

0.26 14/4/02
============

+ Added MAME YM2151 FM core thanks again to BlackAura
+ Fixed credits in About box

0.25 8/4/02
===========

+ Fixed PSG 2-byte noise write behaviour based on chip tests
+ Added MAME 0.36 YM2612 core thanks to BlackAura
+ Finally fixed the seek bug

0.24 25/3/02
============

+ Improved PSG tone channel oversampling (or rather sub-sample accuracy)
  a huge amount - aliasing is gone and it sounds great. It's now always
  turned on.
+ Rewrote PSG noise simulation to be 100% accurate to how the real chip
  works
+ Reverse engineered SMS SN76489 (PSG) feedback network so noise
  pattern is bit-accurate
+ Updated to ZLib 1.1.4

0.23 17/3/02
============

+ Added PSG oversampling, hoping to reduce aliasing effects but it
  doesn't.
+ Improved channel selection, it now remembers it if you stop and re-
  play a track.
+ Released early as I had broken the self-installer last time

0.22 12/2/02
============

+ Total/loop lengths in file info box are now to 1 decimal place,
  rather than rounded down to the nearest second
+ Added some protection for truncated (broken) files
+ Looked into why VGZ files don't show up on the Open dialogue until
  you select them from the dropdown list... it's a Winamp bug, see the
  AAQ above.
+ Worked on the internet download code a bit... note that when you
  close the minibrowser, it tends to switch off IE's offline mode :(

0.21 6/1/02
===========

+ Added HTML display of GD3 information, hopefully allowing Japanese
  text to be displayed on all systems
+ Fixed a memory leak
+ Loads of other stuff
+ Never actually got around to releasing this one

0.2 20/11/01
============

+ Ported the plugin to C
  + so now the YM2413 is emulated via EMU2413
  + ported my SN76489 emulator
  + ported playback engine, including variable-speed playback and
    seeking
  + Re-implemented file downloader using URLMon.dll (makes code simpler)
+ Implemented loop skipping when seeking, so you can seek through a
  file looped a lot of times much faster than before
+ Change title formatting - now you can display Japanese text too (if
  supported).
+ Fixed a bug when stopping/skipping just before the end of the track
+ Moved settings to plugin.ini in the plugins folder. You can delete
  the section from winamp.ini if you like. You'll have to re-set your
  preferences if you don't like my defaults.
+ Changed FM/PSG mixing so the Japanese BIOS music sounds better... if
  anyone can send me a recording (from a real SMS with an FM chip) of
  the Japanese BIOS music (or any game using both the PSG and FM chip)
  I'd be grateful.
+ Added some stuff to the file info dialogue
+ Added YM2413 channel muting
+ Updated to EMU2413 0.51, with modifications

0.12 1/10/01
============

+ Fixed typo in About box (0.1 -> 1.0)
+ Added user-configurable playback rate - now you can choose to play
  music at the speed you remember.
+ Made it so PSG flip-flops don't get stuck at zero frequency (made it
  sound strange sometimes)
+ Changed config dialogue to Verdana font (file info already was)
+ Added useless icon to config dialogue. If anyone wants to design a
  logo I can show it this way :)
+ Fixed tab order in file info dialogue
+ Added SMS Power URL button to file info dialogue
+ Fixed a bug caused by the flip-flop fix
+ Cleaned up source code a lot
+ DLL is now compressed as well as WinAligned
+ Ported EMU2413 to Delphi... but it doesn't work yet
+ Removed the above flip-flop thing because it broke voices...
    On a real SMS, quite often a channel's frequency is set to 0
    without turning it off. On my simulated PSG that leaves a permanent
    DC offset; on a real SMS that offset decays in a fraction of a
    second. The effect of this is to make the wave appear to "move" up
    and down; it has a small effect on the sound, as speakers operate
    better without a DC offset. Unfortunately the same effect is used
    for voices, so when I activate the code to remove the offset,
    voices stop working. To see this in effect, try "Out Run 3D -
    Magical Sound Shower" or "Micro Machines - Title Screen", among
    others.
+ Added HTTP downloading via WinINet.dll... which is part of IE, but
  should be on almost every PC

0.11 4/9/01
===========

+ Fixed a bug in the PSG tone emulation that caused problems with Micro
  Machines.
+ Relaxed version checking, now it only insists on VGM and GD3 1.xx and
  still offers to play other files.

0.1 3/9/01
==========

+ Added a button to set MIME types in the registry. If a server is set
  up to descibe VGM/VGZ files as "Content-Type: audio/vgm" and these
  values are set, Netscape will be able to play VGM files from URLs. IE
  doesn't need it, it ignores the MIME type when it sees the file
  association with Winamp and will open the file properly (after a
  prompt).
+ VGM is verging on going public, so it's reset to 1.00 and the plugin
  gets out of alpha

Alpha 13 26/8/01
================

+ Fixed a worse bug in the previous bugfix :P
+ Added track title formatting stuff
+ Increased play thread priority to stop skipping when the CPU is busy

Alpha 12a 25/8/01
=================

+ Fixed looping bug

Alpha 12 25/8/01
================

+ For some reason the GZip code limited the path to 79 characters,
  causing "Not an AYM file" errors on files with long paths. I fixed it.
+ Switched to VGM instead of AYM. ****DELETE IN_AYM.DLL****
+ Added configuration dialogue; the tone channel checkboxes have moved
  there from the file info box
+ Added looping support
+ Updated to VGM 1.12
+ Added loop configuration to config dialogue, saving the loop count to
  winamp.ini
+ Added a button in the file info dialogue for the config dialogue, so
  you can get at it quicker
+ Setting the loop to a high value allows me to test seeking speed. 400
  minutes in 8 seconds is 3000x...

Alpha 11 20/8/01
================

+ Synchronous noise tested against a real system. Apart from the
  different sound due to the real system's imperfections, it works
  properly now.
+ Updated to use the GD3 tag location properly. Decrease the offset by
  0x14 in existing files for it to work. I'm not going to code for it
  to handle both, sorry...
+ Volumes use values measured from a real SMS. I may switch to
  logarithmic values, or maybe have an option eventually?
+ Speed modifying code added. If you want to play back at 120Hz or 13.
  47Hz, you can. Except you can't, I commented that code out. Thanks to
  Bock for pointing out how to do it.

Alpha 10 19/8/01
================

+ It now looks for and uses the .ayz file extension. It actually 
  doesn't matter which extension you give a file, compressed or not.
+ AYM 1.11, plus you can now choose to try and play versions not in the
  supported range (1.08-1.11).

Alpha 9 19/8/01
===============

+ Switched to AYM instead of DYM
+ Invalid files were displaying a track length before, they don't now
+ Added GZip support. There are problems with the .aym.gz extension -
  Winamp won't automatically pass it to the plugin, because it sees the
  extension as .gz. That has been worked around. Windows won't
  associate . aym.gz files with Winamp, because it too sees them just
  as .gz files. I don't see any way around this. GZip also ballooned
  the DLL size a bit... WinAligning makes it seem even bigger. (Was:
  ~42KB -> 64KB aftar aligning, now it's ~75KB -> 92KB after aligning.)

Alpha 8a 17/8/01
================

+ Fixed problem with DirectSound output plugin
+ Fixed EQ problem


Alpha 8 17/8/01
===============

+ Fixed an error which cause all sound to be half the correct frequency
  (1 octave lower than it should)
+ That also fixed voices


Alpha 7 16/8/01
===============

+ DYM 1.10, with GG stereo port writes. It's untested because there is
  no test stream yet :)
+ Improved method of muting channels, although as far as the sound is
  concerned it's the same.
+ Tweaked volume so the (theoretical) maximum is now 98% of the
  available volume. It seems this is the "right" thing to do...
+ Since compatibility hasn't broken since DYM 1.08 (it uses default
  values for older versions), the version checking now accepts a range
  of values.


Alpha 6 15/8/01
===============

+ DYM 1.09, with the PSG clock rate in the header. That is all.


Alpha 5 15/8/01
===============

+ Fixed up the channel disabling, although it's still in the info box 
  (it'll probably end up somewhere else). Before it took until the next
  volume change on that channel to mute, now it's only the output
  plugin' s buffer length that stops it being instant. Noise can be
  disabled too. Unmuting still needs a volume change though.
+ DYM 1.08 already...
+ Added noise emulation according to the MAME/Hiro-shi method. It's
  terrible, completely inaccurate.
+ Dave's Sonic DYM highlighted a problem - out of laziness, I was not
  buffering the file myself, hoping that Windows would do enough. So,
  every byte read was actually using quite a lot of CPU. I've now got a
  32KB buffer - voices work now (almost... I'm not sure what the
  problem is now, it could be an issue with DYM itself), and seeking is
  incredibly fast! It took 6 seconds to seek 1 minute into the GG
  Shinobi DYM before, now it's instant! Seeking nearly 3 minutes into
  the Sonic DYM takes a fraction of a second. And now, CPU use is way
  down. It depends on the DYM file, but it's typically around 4%, a
  quarter what alpha 4 used :)
+ I switched to my determined PSG clock speed, but it seems to cause
  some problems (with voice) if it's not what the DYM creator used. DYM
  1.09 addition?
+ WinAligned DLL... it's 64KB instead of 45, but it now executes from
  the disk cache on Win98 and higher.


Alpha 4 13/8/01
===============

+ Added proper file info box, without invoking Delphi's RTTI filesize
  overhead. It's a lot more hassle :( but it's kept the plugin at 44KB.
+ Rewrote tone generators to act EXACTLY like the hardware (counters
  and flip-flops). The last version used another method which I thought
  up based on maths and stuff like that, which sounded OK until the
  sound started using vibrato, in which case it sounded terrible. Now
  it sounds perfect (except for emulation of the "fading" 
  flip-flops...). As an added bonus it seems to be a bit faster too,
  the decoding thread uses about 16.2% CPU for me now.
+ Added VERY quick and dirty noise emulation. It's just volume*random(),
  and sounds crappy. It's better than nothing though. It also accounts
  for about 25% of the CPU use...
+ Added DYM version checking, because some people were trying to play
  old DYM files and crashing Winamp... :)


Alphas 1 to 3
=============

I didn't record what I did then...

...but I ought to thank Jason for help translating the C.
    while (! *((int *)b) )
is quite confusing, I think
    while integer(b^)=0 do
is much more readable :) (translation: while what pointer b points to,
typecast as an integer, is zero, do...)


Maxim
http://mwos.cjb.net
http://www.smspower.org