Demos using a GFX mode please !

[Elwood]

Hello everyone and especially demo coders,

2 issues:

1) When Amiga demos will be GFX mode compatible ? I mean, I would like to see some demos in UAE using the P96 emulation, i.e. in full screen mode. But as long as all (all ?) demos are AGA, they can be viewed in window mode only.
Can you please start coding demos using GFX mode (P96 prefered because it will be A1 "native" mode)
Thanks.

2) I noticed that demos are non longer uploaded to Aminet. It's a shame !  :-?
There, the last demos are from parties in 1997 wheras demos can be found in websites for sceners only. Please spread the word, upload your production to Aminet so that every Amigans can download and enjoy your demos.
Thanks a lot.

bye

Philippe 'Elwood' Ferrucci
Jay Miner Society
Amiga Translator Organisation

[carls]

The RTG demos are on their way. Take a look at the releases from Mekka&Symposium 2002 and 2001.

Most of the RTG-enabled demos needs a PPC, however.

The reason for this, I guess, is that in many cases AGA is faster than for example a CV64 on a 68k system.

Take the game Doom, for example. Using FBlit, this is faster in Multiscan 320x240 on my 060 than in the same resolution on my CV64/3D!

Then again, demos are made to impress and show off. And it's more impressive to get 50FPS chunky 3D on AGA than it is on a BVision PPC or a Voodoo3!

If you're looking for demos, scene.org is the place to start. It's the Aminet of the demo scene :-)

PS.
I'm not a coder so correct me if I'm wrong ;-)

[Agafaster]

I heartily agree - spread the work !
it should be out there to be enjoyed !
perhaps even submit some here for download !

[Elwood]

Then again, demos are made to impress and show off.

You're right. This is the reason I didn't post this before. But I think you can impress people by using design and new effects instead of "I made it fast on a slow machine" !  :-)

[darkcoder]

If you like RTG demos, why don't you do them by yourself?
I find the subject a little bit aggressive. Demo coders do demos just for fun  not to impress people not having an Amiga showing them what Amiga can do. Usually it's much more fun to code AGA, or OCS than to use RTG. With RTG is too easy, you just use library functions.
There is also a more thoretical reason, connected with your last observation:
------------------------------------------------
But I think you can impress people by using design and new effects instead of "I made it fast on a slow machine" !
------------------------------------------------

If one wants to "impress people with design adn new effects" than one can use a gfx program, like Photoshop and create very easily wonderful effects. Then you can spend a lot of time using Photoshop to improve your effect. The same goes for 3D: why code it in assembler, when there exists Lightwave?
My answer is that demo-coding is a particular type of computer-graphics. it's computer graphics with a particular architecture. Otherwise it makes no sense. You don't need programming skill to produce impressive computer graphics, just use good rendering package and eventually an SGI workstation. But you need programming skill if you want to produce good effects WITH A PARTICULAR MACHINE. So demo coding, IMHO is: choose a platform and do stuff with THAT platform. Portability doesn't matter. What is the meaning of a masterpiece like "Arte" produced with a P4. You can appreciate the design, ok, but this is a matter of graphicians. You cound'say that "Arte" is a masterpiece of coding if it run on a P4. but "arte" is a masterpiece of coding because it runs on A500!
So why not to choose RTG as a platform? Because RTG is not a platform, it is a standard. Many different CFX cards use RTG, hopefully more in the future. But all these gfx card are different, they have different features and speed. How can a coder program "the best way"? There is no way which is best for each gfx card.
Ok, this is my opinion. Many coders have different opinions, so there are RTG demos around. But I think most coders have ideas similar to mine. That's why PC scene never became as great as the Amiga one. Nowadays many coders prefer to look at alternative platform, like Dreamcast, Xbox or even Gameboy Advance.

The Dark Coder

[carls]

@darkcoder

I totally agree!
Coding is as much a form of art as painting or composing!

[Karlos]

IMHO, RTG is best for those who are interested in exploring really cpu driven effects or those with highcolor rendering etc. RTG is essentially a fast pixel rasterizer and not much else.

Far more interesting things can be done by battering the custom chips and this is an area which is a lot of fun to poke around in (all puns intentional).

My gripe is with those demos that are AGA only yet do bugger all that's particularly AGA specific and could be presented at higher framerates / resolutions etc. under RTG (unless of course the coder has no RTG hw for whatever reason).

New hardware will more than likely breed it's own demo scene so those wanting to see what their turbo charged systems are capable of just need to wait a while. A1 users should be used to that by now ;-)

[Johan Samuelsson]

You can find a lot of GFXCard compatible demos
at http://www.gfxbase.com ...
and all Up Rough musicdisks are GFXCard compatible.
Go to http://www.ponnyslakteriet.com/uprough and
download all eps/singles/lps (musicdisks) !!...
Enjoy!... =)

[mahen]

DarkCoder: actually, what you say is exactly what I was fearing :

there won't be any scene on the new PPC machines (powered by morphos, os4) because they're just standard hardware and makes them not different from PCs for demos. ?

And also : nowadays, demos on computers lost their point because computers are getting continuously more and more powerful, coders don't care about optimisation and just add tons of 3D effects.. ?

So the amiga demoscene will die with the AGA chipset, or lose their spirit ?

Can anyone reassure me ? Is there a spirit that can be pursued on the new ppc machine (optimization, passion, ...). ?

[dezignersrepublic]

Try back2roots.org they have loads of demos all the way from ecs to hd P96 ones...

[darkcoder]

First of all I apologise for being a little bit though in my previous posting.

I agree with carls that coding is an art. What I wanted to specify is that, IMHO, coding is not "the art of producing beautyful effects", but rather "the art of producing beatyful effects BY PROGRAMMING". And because this extra requirment you introduce, you need to specify an hardware
which gives you some limits and you have to reach the limit of the hardware by coding. If you don't fix a limit to the hardware (and with RTG you have no limit) it's useless to use coding, just use gfx applications and an hardware powerfull enough.

@Karlos you gave a good point. However, I still don't see the sense of RTG demos for the following argument: with RTG you can use many differeent gfx boards having very different features (which IS a good thing for everything but demo-coding). If you want a demo running on all the gfx cards, you have to consider the slow ones and you don't use the most powerful features of the others. On the other hand, if you say "this demo requires ATI Radeon card" then you are forcing the use of a particular hardware.
Still anotherr issue is that modern gfx cards are TOO powerful. They implement many many effects in hardware. So IMHO, with these cards there's nothing left to code. For example, a 3d demo could be something like this (I am actually NOT a RTG coder so I invent function names)

 lea CyberGfx_base,a6
 move.l PoligonList,a2
 move NumberOfPolygons,d0
.loop
  move.l (a2)+,a0
  jsr RotateVertex(a6)
  jsr ComputeVisibleSurfaces(a6)
  jsr RenderTexturedSurfacesInPhongWithZBuffer(a6)
 dbra d0,.loop

where the subroutines are NOT pieces of code but just computation done by the hardware. So, where's the fun in coding such a stuff? You don't need any programming skills just learn how to use an assembler. Is similar to what AMOS was, except that AMOS was not powerful enough to produce good result, while these monster chips are. But if it's so easy to produce wonderfuleffects by programming, why use programming at all? Just use Photoshop and concentrate your efforts just on the aestetical aspect.

@mahen Well..first of all these are just my ideas. But maybe people will have fun coding just doing a sequence of library calls...
Anyway the scene is not only coding: there is also gfx, music, writing diskmag and for all these things RTG is a VERY good thing. I think the spirit will stay alive. But you are interested in optimized coding, IMHO, you better consider different platform: consoles or (very, very interesting IMHO, PDA devices). And use your Amiga or Pegasos for every other thing.

The Dark Coder

[carls]

@DarkCoder
The Amiga scene won't die.
Just because it's an A1200 doesn't mean it's not an Amiga!
Look at the C64 scene: it's still alive!

There are so many different platforms to make demos on nowadays that it's getting more and more common to watch demos as recorded DivX films instead of the actual executable (there is a dreamcast scene, PS2 scene, PSX scene etc.)

The Linux scene is also growing and the AOne is already out there running Linux!

There will most likely be an OS4 demo scene, too. If you're just into optimizing code, how about optimizing it for the 68K emulator? :-)

[Hardboy]

Some of you are missing som points:

Since the 68030 became standard(~1995?), most of the demos have been 3D effects mixed up in a C2P, trying to tweak as much as possible out of the low memory bandwith...

All this could just as well be made PPC,RTG, whatever, it´s up to the coders.

[MagicSN]

>If you like RTG demos, why don't you do them by >yourself?

Stupid argument.
                                                   >I find the subject a little bit aggressive. Demo >coders do demos just for fun not to impress >people not
 
And why should this not be possible on RTG, having fun with coding ? Remember - many people (me included) don't have the HARDWARE anymore to display OCS/ECS/AGA. So if a demo does not support RTG we cannot watch it !

                                                  >than to use RTG. With RTG is too easy, you just >use library functions.
 
Again, stupid argument. There is no such thing
as a "demo effect library" - and if there would be you could choose not to use it. Basic RTG-Coding
is quite primitive. It is just "copying a Chunky
Array to the Screen". I do not see where the
big advantage of putting a planar array to the
screen is ? (okay, you can do some tricks with
transparency and stuff, but on the other hand the
hardware is slower - and there are Demo Effects
which will work better in Chunky Format also).
The PC Demo Scene is using Chunky Format since
a very long time. Sure, some of their demos are
boring, but there are also really great demos there...
                                                   >But I think you can impress people by using >design and new effects instead of "I made it fast >on a slow machine" !
       
Again: Most people will not be able to view a
Demo without RTG Support. And well - what's so
special about AGA that demos should not be allowed to be not AGA ? I don't see anything there...
asides maybe that a lot of demo-coders are very
reluctant (luckily not all of them ) to look
into something new. Generally the ones who are
against RTG Demo are the ones who have no clue
about RTG Coding... sounds strange, doesn't it ?

BTW: It is easy to code the demos in a way they
run on both Chunky and Planar Hardware. Usually only THREE FUNCTIONS will differ (opening a screen, closing a screen, copying data to the screen). Of course you have to keep some "rules" (no hacky stuff which breaks the OS, everything
in Chunky Format).

>to improve your effect. The same goes for 3D: why >code it in assembler, when there exists >Lightwave?
 
This proves no argument against RTG-Supporting Demos...
                                                                                               >MACHINE. So demo coding, IMHO is: choose a >platform and do stuff with THAT platform. >Portability
 
Yes, and on Amiga these days this platform is
a PPC-based RTG-System                          
                                                   >                masterpiece of coding if it run >on a P4. but "arte" is a masterpiece of coding >because it runs on A500!
 
The question is: Couldn't the demo be done so that it runs on BOTH an A500 and a RTG-System? i think this should not have been so hard

                                                   >different CFX cards use RTG, hopefully more in >the future. But all these gfx card are different, >they have different features and speed. How can a >coder program "the best way"? There is no way >which is
 
Bah. You only have to care about this if you want
to support 3D Hardware (unlikely for Demo coders). If you use the GFX Card only as a Chunky Buffer
you do not need to care about this. There are only so many ways to copy an array into a chunky buffer. Sure, some might be a bit faster, but the same is the case for AGA Demos too... sometimes a programmer has a slightly faster approach (for example c2p).
                                                   >Ok, this is my opinion. Many coders have >different opinions, so there are RTG demos >around. But I
 
An opinion totally - please forgive my words -
unharmed by any knowledge about what RTG is
actually about If you want to discuss on an issue, you should at least know the BASICS of the issue - and not say "I don't know what I am talking about, but I don't like it".
                                                   >hand, if you say "this demo requires ATI Radeon >card" then you are forcing the use of a >particular
 
Such a thing would only happen if you would support 3D Hardware (which is highly unlikely for Demo Coders to do).
                                                   >Still anotherr issue is that modern gfx cards are >TOO powerful. They implement many many effects in
 
You do not have to USE the 3D Hardware. Use the GFX Card simply as a chunky Buffer, like the Demo-Coders on PC. Basically your API is

- Open a Screen
- Get the Base address of where the graphics
  data of the bitmap starts
- Change the Colors
- Perform Multibuffering
- Close the Screen again

That's *all* you need. What's here so different
to Demo-Coding under Planar hardware (asides from that it is chunky then...).

I fully understand that Demo Coders don't want to
use "lame 3D Hardware Support" - after all they
want to show their coding skills, *not* the powerful 3D Chip.

On the other hand they should go sure people can
actually WATCH their demos. And with requiring
Planar Hardware (most modern monitors do not
support 15 kHz frequencies anymore) people CANNOT.

If you need any help adapting your demos to RTG (so it can run even on both, RTG and AGA) contact
me privately, and I give you some hints. You need
of course to go sure that you render in Chunky-Format (alternatively you could use a p2c algorithm, to convert to chunky format - which will of course cause a slowdown, but on a fast GFX Board the bad effect should not be THAT bad anymore).
           
There's nothing magic in RTG. The main difference is:

AGA: You first define the first bitplane, then the next, and so on...

RTG: You have all bitplanes in one value...

Simple Example: (4x4 pixels in 4 Bit)

AGA:

1001 1100 0101 1111  
1001 1111 1111 1111
0011 0000 1111 0000
1010 1010 1010 1010

RTG:

11 ("1011")
0
12 ("1100")
7 ("0111")
...

Steffen Haeuser
                                           

[carls]

@MagicSN

First: Correct me if I'm wrong, but as long as you write directly to the graphic card's memory I don't think it could be classified as RTG?
RTG implies some kinde of HAL or it wouldn't be retargetable...

I get your point, but here's how I see it:

There is a big difference between the Amiga and the PC demo scene.

At work, I've got a PIII 667MHz with 256MB RAM and a 32MB 3D graphics card (from Matrox I believe), and an AC97 soundcard. I'm running Win2K with the latest versions of DirectX etc.

Still, many of the demos I download won't work for a number of reasons. Sometimes there's no sound. Sometimes the graphics are distorted. Sometimes it is just plain SLOW although the effect shown on the screen is similar to one that runs smoothly in Amiga demos on my 060! And these are demos that has won compos on big parties so they must have been working on at least the compo machine.

There's also comments in the file_id.diz (or whatever textfile is included): "Will only have fog on graphics card so-and-so", "Sound will be jerky on slower computers". SLOW? My 667MHz PIII is SLOW?

If you download a compo-winning AGA+060 demo, you know that it will look the same on all Amigas. The sound will be correctly synced with the effects, it will keep a decent framerate, etc.

I downloaded some RTG demos from M&S last year and they were so slow on my CV64/3D I could barely watch them.

Custom hardware is what built the demo scene and I can fully understand why many coders stick to AGA.

I am not impressed by a demo doing 100FPS on an NVidia card. If I want to be impressed, I watch Hotstyle Takeover or The Castle (Loonies/Amiga) or Mathematica (Can't remember the group/C64).

Any decent graphician and musician can create the right audiovisual feeling in a demo, but not every coder can make it look as intended using 2MB graphics memory and a 50MHz 060.

Oh well, maybe I'm just a crazy "oldschool" guy :-)