Re: DHR graphics can be good (was Re: Bill Budge & pinball)

[sknkwrks@sonny-boy.cs.unlv.edu (Scott Alfter)]

In article <C67qL0.76B@news.iastate.edu> irsman@iastate.edu (Ian Schmidt) writes:
>The IIe has the same sound as a stock PC (actually that's vice-versa :) and
>nice things can be done with it at the expense of CPU time...someone on 
>comp.sys.amiga.audio brought up the spectre of a IIe-based MOD player
>(It could most likely be done with a RamWorks or similar card if someone was
>really masochistic...Scott Alfer has left the building so it doesn't look like
>it's gonna happen though ;)

(Hey bub, that's "Alfter," not "Alfter." :-) )

As it is, SoftDAC is pretty much stretched to the limit just playing
digital audio at ~11.025 kHz.  I don't know all that much about the
MOD format, but I'd guess that non-Amiga MOD players work by
maintaining some sort of timing relationship between up to four
samples at once (out of a maximum of 30 or so), summing the samples at
the proper volume level, and shoving them through some sort of DAC
arrangement, either in hardware or software.  A MOD player for the IIe
might be possible if a hardware DAC is used...it could be a couple of
chips on a card, but how many IIe users have empty slots?  I only had
one slot (3) free in mine before I upgraded the system to a IIGS (I
now have four slots free).  SoftDAC's timing is tight enough as it
is...asking it to play MODs without throwing extra CPU power (not
available for most 8-bit systems) or extra hardware (which defeats the
purpose of a software-only player) would more than likely push things
too far.  (Then again, I'll bet nobody thought SoftDAC could be done
either. :-) )

There's a program available for UNIX boxes, though, called mod2au.
This program will convert MODs into Sun audio files.  sox can then be
used to convert from Sun audio (8.192 kHz 8-bit mu-law) to the format
SoftDAC uses (11.025 kHz 8-bit PCM)...in a roundabout way (read: with
some preprocessing on another system), you can already play MODs with
SoftDAC.  You'll need a shitload of RAM, though...if I recall properly
the way SoftDAC uses memory, each megabyte of RamWorks memory will
give you about 2:20 playing time.  Considering that you can get up to
3 megs onto a RamWorks, that yields a playing time of about 7
minutes...enough to handle most MODs, but who has 3 megs of RAM?
Also, who wants to download up to 4512K files from the local UNIX box
just to play a MOD?

(There's also the consideration that mod2au's output isn't always the
best in the world...batdance.mod sounds particularly nasty after
running it through this conversion.  It's probably the result of the
relatively low sample rate of Sun audio files.)

I'd still like to throw some more features into SoftDAC if I ever get
the time, though...probably the most important would be the ability to
use the program without a shell (even if it's something as crude as
requiring the user to type in a name instead of a nice point-and-shoot
system).  For my own use, I'd like to add the ability to take
advantage of the IIGS's audio hardware if it's available...this would
make SoftDAC a one-stop sound solution for 8-bit and IIGS systems.
(It'd also mean that I wouldn't have to fire up the Finder every time
I want to play a sound...I boot into ProDOS 8 about 90-95% of the time
since it's so much faster (only a second or two) and most of the
software I use is 8-bit anyway.)  Sound-manipulation software is also
a possibility...and who knows--this could even mean a MOD-conversion
routine.  Don't take all of this as a bunch of promises, though...I
don't know where the rest of you find time for writing prodigious
amounts of code for the II, but I usually do good enough to keep up
with email and news (as it is, I typically go 1-2 weeks between GEnie
logins).

  _/_   Scott Alfter                             Internet: sknkwrks@cs.unlv.edu
 / v \  Call the Skunk Works BBS today!           Ask me about SoftDAC--digital
(IIGS(  (702) 894-9619 300-14400 V.32bis          audio for your Apple IIe/IIc!
 \_^_/  ----=====##### Don't blame me...I voted for Bush/Quayle! #####=====----