Oldskooler Ramblings

the unlikely child born of the home computer wars

Archive for the ‘Demoscene’ Category

Upcoming Trixter Sighting + Retroprogramming

Posted by Trixter on May 15, 2013

June 14-16 you should be able to see me at @party in Boston.  (If anyone is looking to share a hotel room, drop me a line!)  I am scheduled to give a 30-minute version of the PCjr presentation I had worked on for NOTACON, and hopefully enter a compo or two with some oldskool hardware I will be shipping to arrive ahead of me.

Speaking of entering a compo: I really, really dig retroprogramming.  The cool part is, after 10 years of retroprogramming in spare time, my kung fu is getting advanced enough where I not only know how to do what I want in assembly, but I know the fastest possible method to getting it done on the target hardware. For example, I recently implemented a vertical-retrace interrupt in software because the hardware one wasn’t good enough. It’s sick that I know how to do that, but sicker that I know why I need to do that.

I still get a kick out of impressing Jim-of-20-years-ago.

Posted in Demoscene, Programming | 7 Comments »

Maze Generation In Thirteen Bytes

Posted by Trixter on December 17, 2012

Update 12/7/2012 @ 13:46: Peter Ferrie smashed my record by a single byte, so the record is now held by him at 12 bytes.  Congrats, and I feel like a fool for missing it :-)  I’ve tacked on his optimization to the end of my original post.

Update 1/7/2013: herm1t further smashed the record, down to 11 bytes!

Update 1/7/2013 @ 18:00: Peter bounces back and reclaims the record with 10 bytes! It kind-of breaks my target platform (uses an undocumented opcode that only works on Intel processors) but hey, a record’s a record! I’ve updated the article below.

In the past, when I’ve had a democoding breakthrough, I kept quiet and either used my discovery in a production, or just bragged to my demoscene friends privately.  However, my opportunities to achieve democoding “world firsts” are just about gone, and size coding compos seem to be dead, so I’ve decided to just write a blog post about what I’ve done instead: I’ve written a maze generator in only 13 bytes of x86 machine code.

Read the rest of this entry »

Posted in Demoscene, Programming, Vintage Computing | 20 Comments »

MindCandy Black Friday Deal

Posted by Trixter on November 23, 2012

A year ago, myself and a few friends completed our demoscene video trilogy with MindCandy Volume 3.  This was the first volume to be rendered at 60 frames per second for Blu-ray; it makes for a great home theater showcase.  Like all MindCandy volumes, most of the demos contain commentary from the original authors, so you can get some insight as to how they got their ideas and programmed the effects.

We still have some left, so we’ve lowered the price for Black Friday (and the rest of the holiday buying season) down to $17 for the US and $19 for Canada.  (If overseas, you can try Maz Sound, CSW Verlag, and Amazon UK for the best deals.)

Posted in Demoscene, MindCandy | Leave a Comment »

Reverse-engineering an old wound

Posted by Trixter on November 8, 2012

Nearly two decades ago on the usenet newsgroups comp.sys.ibm.pc.demos and comp.sys.ibm.pc.soundcard, there were some accusations flung around that Josh Jensen (Cyberstrike of Renaissance, for those who still remember the PC demoscene) had copied entire chunks of Mark J. Cox‘s MODPLAY to use in his own modplayer SuperProPlay (and later MASI sound system). Just as time has a way of healing old wounds, advances in technology has a way of ripping them open again, and a chance encounter with some familiar assembly code in October got me thinking about the accusations against Jensen all those years ago. I didn’t give it much attention back then, but I’m a different person now, with much more skill than I had 20 years ago. With decades of x86 assembler, reverse-engineering, and programming skills under my belt, I decided to take another look at this issue to see if it could be answered definitively. I armed myself with much better RE tools (IDA) as well as Josh’s released Protracker Playing Source (PPS) v1.10 source code (PPS110.ZIP) and spent about an hour looking at them both.

My verdict: Josh quite absolutely copied entire chunks of MODPLAY for use in his own code.

Read the rest of this entry »

Posted in Demoscene, Programming | 2 Comments »

The esoteric side of DOS-era soundcards

Posted by Trixter on August 30, 2012

A user on a vintage computing forum recently asked if anyone had an Adlib Gold for sale.  Actually, pleading would be more accurate, because the Adlib Gold is an exceedingly rare card due to being completely crushed in the marketplace by Creative.  (Which is a shame, because the Gold had much better digital and FM sound quality, but as many industries illustrate, being first (or best, or even first+best) in the marketplace does not guarantee success.  Microsoft and Apple have many interesting multicolored stains on the soles of their boots.)

I’m one of the people this user probably hates, as I own not one but two Adlib Golds, one loose and another open-but-hopefully-complete-in-box. (I also have three IBM Music Feature cards, as well as an MSound Stereo, giving him four more reasons to hate me.) And until I get my “Sound Card Museum” project up and running, and have the card fully documented, I’m unwilling to let either of mine go.

But it got me thinking:  If you want to have fun exploring a high-quality, quirky, or just historically interesting sound card for your vintage rig, there are plenty of other options that grace ebay on a semi-monthly basis.  For example, the Pro Audio Spectrum series is interesting in that one of the models (maybe more?) can be put into an 8-bit ISA slot and give even a lowly 808x machine 16-bit 44.1Khz stereo sound. Later PAS cards had 3D in the name (Pro 3D Spectrum IIRC) and had a “surround” bit you could flip for some fake surround. Some clone cards could do all sorts of wacky emulation; I have an Aztech Sound Galaxy NX Pro 16 that can emulate the Covox Speech Thing and Disney Sound Source. Some cards somehow manage to tap port ox60 so they can route PC speaker sound through the card (and some Sound Blasters and other cards have a cable jack that plug into the motherboard for that). The Sound Blaster 16 ASP has a programmable DSP that can be used for realtime compression/decompression of ADPCM audio as well as QSound, although only one game supports the ASP that I know of, name escapes me at the moment. You can almost always find an MT-32 or an LAPC-1 on ebay now and then, and those will obviously add dimension to most games published from 1989 to 1993. For truly amazing General MIDI sound, you can still sometimes find the original Roland SCC-1 which not only practically defined the GMIDI standard but still remains one of the best-sounding cards for GMIDI (some of the MIDI files that actually use the GS extensions sound pretty damn amazing). While high-end and not very compatible with games, the Turtle Beach Multisound has really great MIDI wavetable that should be heard at least once.

King of the “interesting” sound cards is the Gravis Ultrasound. Very wacky, very capable, very limited, very unlimited. It can produce simultaneously the very worst and the very VERY best sound you’ve ever heard, depending on how well the application programmers understood the card. Some games get small speed-ups with a Gravis card because it is capable of playing up to 32 digital channels out of its onboard wavetable RAM, giving the CPU some more time to render frames. You can put the Gravis into any 286 or higher that has a true NMI. If you put it in a 386 or higher, find yourself some demos that support the GUS and prepare to be amazed at what your old slow computer can do. (Bonus non-sound-related hint: You can get Doom (not Doom II) running at nearly the full framerate on a 386-40 by hitting F5 as soon as the game starts to throw it into low-res mode.)

Sometimes a very uninteresting/dull/plain card can be put to very interesting uses; for example, DOS-era MPC-era gaming, where the audio consists entirely of redbook audio tracks (even the interactive speaking parts). This is something that emulation still has some trouble getting right (namely, the sync is delayed/off/slips), but on real hardware it usually works. I have a Tandy 2500 sx-25 that has a CDROM interface card with stereo RCA jacks — it’s perfectly capable of playing Jones in the Fast Lane or Loom or Monkey Island (MPC edition) or INCA or any other redbook audio-based game with no sync issues whatsoever without needing a secondary sound card (although having a real sound card adds more dimension to those games).

And finally, if you want to give even a truly shitty card the opportunity to sound awesome, grab yourself some decent Amiga MODs (or .S3Ms, or .ITs, or .XMs) and fire up a decent modplayer (or better, the tracker that originally created them). A 386-25 can calculate 8 or more digital channels mixed together in decent quality realtime and then feed that to your crap SB clone. If you have a Tandy TL/SL/RL machine with the built-in DAC, “TANTRAKR” is an excellent modplayer that uses the DAC and even on an 8086 can play 4-channel MODs decently.

You can even have some fun with the Covox Speech Thing (and other LPT DACs like the Disney Sound Source). The Covox by itself isn’t very interesting and also draws quite a bit of CPU when playing audio, but if you have the [B]software[/B] that came with the Speech Thing, it gets more interesting. The software contains some interesting utilities including an 8:1 speech compression method that actually works (modified CVSD) as well as a 2:1 compression scheme that works very well with music. Don’t have a Speech Thing? Build your own using a handful of resistors and some wire!

So yes, it is unfortunate that the Adlib Gold is somewhat of a holy grail when it comes to PC DOS-era soundcards, but that doesn’t mean you can’t explore some other dark corners of DOS audio.

Posted in Demoscene, Vintage Computing | 32 Comments »

Memories of NAID

Posted by Trixter on June 6, 2012

In anticipation of the NAID organizers visiting @party this year, and unable to attend myself, I spent some time working up a video DVD of all the high-quality NAID footage I had copies of.  It’s called “Memories of NAID” and includes the following footage:

  • “NAID ’95″ tape compiled by the organizers
  • “NAID ’96″ tape compiled by the organizers
  • “IC and Soundgun do NAID ’96″ by IC, with a 2012 introduction by IC
  • Four local news programs on NAID ’95
  • 8 minutes of NAID ’95 registration and guestbook signing with lots of familiar faces
  • 2 minutes of NAID ’96 classroom footage

It’s a little over 2 hours of footage of the height of the 1990s NA demoscene.  Also included on the DVD-ROM section is Phoenix’s NAIDorabilia which is all of the demos, music, party reports, and other miscellany associated with both NAID parties.

The footage is fully interlaced, preserving that “video verite” look. I chose to distribute it as a DVD because that was the only way I could guarantee people would see all 60 fields per second. (Unless something has changed in the last year, no online streaming video service (Youtube, Vimeo, etc.) supports 30i material properly… although that’s a moot point anyway, since there is some very well-known copyrighted music in parts of the footage which would probably get it rejected from such services anyway.)

You can download the DVD .ISO at archive.org, but if that is gone for some reason, there is a slower download link here:  ftp://ftp.oldskool.org/pub/misc/Video/MemoriesOfNAID.iso

Posted in Demoscene | 10 Comments »

MindCandy Volume 3′s First Review

Posted by Trixter on November 30, 2011

Blu-ray.com gave MindCandy Volume 3 a Recommended rating with 4 out of 5 stars, and I couldn’t be happier.  I really respect blu-ray.com’s reviews for their specific coverage of picture quality, sound quality, and extras — the things that blu-ray massively improves on over DVD — so getting a good rating from them means a lot to me.  Picture Quality got a 5 out of 5, of course :-)

One of the things we got dinged on was the audio rating (3 out of 5), not because the sound was bad, but because the audio tracks weren’t lossless.  I agree lossless audio would have been best, but we couldn’t use lossless because of a technical limitation in Adobe Encore.  Encore had trouble dealing with .wav files over 2gig, which was the original RIFF .WAV format’s limitation (the W64 and RF64 extensions to .wav have overcome this, but Encore doesn’t support them).  At 3.5 hours of stereo audio @ 48KHz @ 24-bit resolution, a lossless track is 3.6gig.  I ran into odd random problems trying to use lossless 24-bit audio, but had no problems at all using Dolby AC3 audio.  So I chose the devil I knew.

Posted in Demoscene, Digital Video, Entertainment, MindCandy | 6 Comments »

MindCandy Volume 3 Is Now Available

Posted by Trixter on November 22, 2011

After 4 years of hard work and many setbacks, I’m very pleased to announce that MindCandy Volume 3 is finally available.

The official launch date is December 6th, however the first shipments will be going out to people who pre-ordered as early as Friday of this week.  You can order directly from us, from a reseller in your hemisphere, or from Amazon.

I’d like to thank the entire MindCandy crew past and present for getting “that  demodvd project” to this point.  From capturing some clips of a Capacala demo in 1996, to a professional Blu-ray in 2011 with over 3.5 hours of demos and 7 hours of extras, it’s been a long great ride.

And special thanks to my family, for putting up with me and my hobby :-)

Posted in Demoscene, Digital Video, Entertainment, MindCandy | 12 Comments »

MindCandy Volume 3 sent to replicators

Posted by Trixter on October 14, 2011

After 3+ years of setbacks, MindCandy 3 was sent to the replicators ths morning.  Assuming there are no further issues, we should be shipping at the end of the month!

Update: As corrected by Dan, pre-orders before Black Friday and launch in December.  Assuming no problems at the replicator, of course.

Posted in Demoscene, Digital Video, Entertainment, MindCandy | 6 Comments »

Blu-ray media size mismatches

Posted by Trixter on October 3, 2011

This weekend, I finished the second (and hopefully final) Blu-ray release candidate for MindCandy 3.  (The DVD-9 is already final.)  Some major tweaks involved normalizing the audio across the entire thing, and a minor tweak was to re-encode the main video at a higher quality, so it could grow larger, so it would need to be split across layers, so that the disc is more compatible with old hardware players (it seems that if you’re going to do a layer break on a Blu-ray, it should be in the largest file, as there is apparently a minimum acceptable filesize for the break).  The size of the disc grew to about 46GiB, but since a Blu-ray is 46.6GiB, we were still under (by a hair).

Well, imagine my surprise when I tried to burn it to my rewritable test disc and saw this:

Considering our premastering tool is highly accurate, and hadn’t shown any errors when I was premastering the project, this was confusing.  Fifteen minutes of research didn’t pull up anything concrete other than someone claiming that BD-RE discs take a few hundred meg as “reserve space”, whatever that means.

Rather than trust tha interwebz, I decided to check the media sizes of my rewritable BD-RE DL (50G) disc, and a regular BD-R DL (50G) blank using the media information window of ImgBurn.  Results:

BD-RE DL: Sectors: 23,652,352, Size: 48,440,016,896 bytes
BD-R DL:  Sectors: 24,438,784, Size: 50,050,629,632 bytes

Well look at that:  A rewritable dual-layer blu-ray has nearly 1.5 gig less available space than a regular blank.

Now you know!

Posted in Digital Video, MindCandy | Leave a Comment »

 
Follow

Get every new post delivered to your Inbox.

Join 147 other followers