Oh by the way, ervery one of these works and plays through to the end. Keep in mind these programs sometimez utilized hardware microcode hacks so dont be surprised if there is a slight glitch every now and then, but they will for the most part work. They wont damage DosBox or your system in any way. I love the sound of 8 bit stereo, hehe!

yeah, i remember 2nd reality & unreal, both are great. for a lot more cool demos visit http://www.scene.org

Come to think of it I think thats where I got these, hehe 😁 Good ol hardware hacks FT Special effects 😜

2nd reality is still awesome!

Ah, yes, these lovely old classics. You know, I think the DOSBox guys should add a Demo Compatibility listing to the DOSBox website. All the tweaks present in these sort of programs provide an emulator with the ultimate test. If it can run these sort of programs perfectly, it'll run any game.

I wouldn't count on that statement
Demo's don't need file acces.
Rarely need mouse acces.
etc.
etc

Qbix wrote:

I wouldn't count on that statement
Demo's don't need file acces.

Only on the inital loading of a segment or the demo as a whole, depending on the approach taken when writing it. As far as I know, DOS games only tend to access the hard drive when loading a level, and nothing after that until the end of the level.

Besides, with all the sound, video, and other programming tricks used by the authors of demos, you're probably more-likely to weed out bugs and missing features in those areas using demos than if you use games. Remember, demo authors tried to make every last CPU cycle count for something and pull off as many interesting tricks as possible with the available hardware, including the sound and video.

I've got one demo that doesn't work under DOSBox because it needs VGA hardware functions that DOSBox doesn't have yet. Shall I post a zip of it?

There are plenty of demos that don't work because they're using special
vga tweaking. Emulating this would mean a great speed decrease, so
it won't happen.

maybe you could implement different vgas one day. something like vga-normal and vga-full, which would implement everything possible. the speed decrease will most likely be irrelevant in a few yours. but i understand that this also most unlikely before, let's guess, dosbox 0.92. :)

It is very unlikely because the focus is on games ONLY.

It wasent uncommon though for DIY PC vendors to use demos like these to shock 😲 and awe 😮 potential customers as to the ability of the machine. They are a good meens of testing a machines coping ability with graphics, cpu, memory and sound. They are almost like benchmarks withought metrics. However as mentioned before they don't neccisarrily test peripherals, or the file system. Alot of the effects included in demos where implemented in games, hence the term demo as a meens of showing what could be done in a game 😀 .

Demos were a hell incompatible by times, just look at their
requirements (no memory manager etc.). That's why games
mostly used similar effects, not the same, simply because they
wanted to sell the games.
Nevertheless, many demos already run under dosbox, and even
with the dynamic core.

Yeah your probably right, but as long as you have the hardware listed, your good to go. Usually most demos where written for Soundblaster PCI or Gravis sound cards and could use generic VGA devices. Best bet though is to run em on native hardware. Native DOS era hardware is hard to come by these days and so there is DOSBox 😁 .

When I discovered DOSBox I was amazed how well it handled the old scene demos, given that some of them use really nasty tricks to get the maximum performance out of the machine. And the GUS emulation helps a lot, since watching demos without a GUS is a rather frustrating experience 🤣

Some weird demos work even better under DOSBox, or has anybody ever got Optic Nerve running on a real machine? (I could watch it once on my old 386SX, it crashed in the middle and I never got it working again on any system in 10 years, yet in DOSBox it runs without a hitch 😁)

The VGA emulation in DOSBox is good enough for at least 90% of the VGA register tweaks, for the rest of them, DOSBox would have to emulate a typical old VGA CRT monitor as well (which means much work just to get a handful of demos running).