Demos using a GFX mode please !

[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
                                           

[MagicSN]

Hi!

> 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?

No, that is still RTG.

>RTG implies some kinde of HAL or it wouldn't be >retargetable...

Well, sure:

LockBitmapTagList
UnlockBitmap
LoadRGB32
OpenScreenTagList
CloseScreen
OpenWindowTagList
CloseWindow
AllocScreenBuffer
ChangeScreenBuffer

I'd say this *is* a HAL

>                                          Still, >many of the demos I download won't work for a >number of reasons. Sometimes there's no sound. >Sometimes the graphics are
 
Bah, stupid PC coders Since when is that something is done bad on a PC an argument for us ?
That's exactly the sort of fake-argument I usually read from AGA-fanatics. Please define what's so great in AGA ? If you look at it it boils down to "I like it. I am used to it. I never did anything else.". And nothing more.
                                         >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.

Well, then an RTG-version of these demos should
be even faster

>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

fog == obviously they use 3D Hardware. And we
did agree on that we don't use 3D Hardware for
"oldschool" demos, didn't we ?

>                                          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
 
Again: There is nothing magic in AGA. You can achieve the same on RTG using the GFX Board
as a simple Chunky Buffer. Only most demo coders (most !!!) "don't like what they don't know". And of course as they don't like what they don't know they never will have a closer look - so will never
know it - so will never like it

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

Maybe these demos were just coded badly ? Or they
used 3D Hardware (which is simply a PAIN on the CV/3D). Or they used Highres graphics. Which won't be fast on EITHER AGA or RTG (with some exceptions, maybe...) as long as no 3D Hardware
is used.

For a good comparision you should do the same demo - once for AGA, once for RTG. And you will notice the RTG version will be faster (just usually nobody does a demo for both AGA and RTG...). Some early RTG-Demo also still did their graphics layout in Planar graphics (as for AGA) and then converted over while displaying...

But principially you can do what you do in AGA
also on RTG - only faster

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

Believe it or not - a GFX Card is also Custom Hardware. Just custom hardware which implements a standard (but if you look at the direct-hardware coding of a Card it will look very "Custom" to you... no two Cards do the Card Init the same way it seems...).

>                                          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
 
I did not read any reason yet why we should use
slower Hardware which is less available.
   
>Oh well, maybe I'm just a crazy "oldschool" guy  

No I think just that many people with an attitude
like you have prejudices against OS-clean coding.
That's the matter to what it comes down in the end... and if they don't know something they don't want to have anything to do with it. At least many of them are like this.

Steffen

[MagicSN]

Hi!

>Q[r]COV - intro contribution to Flag2001 by Industry >and Pas Maters. This runs on both AGA and CGX >with some quite simple chunky effects.

>I have an A1200/060 50MHz with a Z-IV busboard >and a CV64/3D, and one A1200 with AGA and an 030 >28MHz. This intro operates best on 060 using AGA, >while 060+CGX is not remarkably faster than on the >030+AGA. It runs in 8-bit lowres on all three

But it does not run faster on AGA either,
right ? The point is not the faster speed on GFX Boards (though it exists, see discussion below), the point is that most people just CANNOT view anything which uses AGA, while they can, if it supports RTG.
And it is not really as if one of AGA/RTG would be
cooler/easier-to-do-demo-effects-with or whatever.
It is just a simple choice what to use. And to use the
one people cannot use anymore (and which also definitely won't run on A1 even IF people have still a 1084 monitor) sounds stupid to me.

As to the speed: Try a 16 Bit Display on AGA and compare this then in speed to a 16 Bit Display on GFX Board (We tried this on Heretic II, but the AGA version is really remarkable slower...). Or try 640x480 on AGA... this is also very slow (which is
why Freespace requires a GFX Board). Even in Lowres though GFX Boards are faster. Of course in cases where 90% of speed is for the calculation and only 10% for the screen refresh even a 2x as fast GFX Board won't make much of a difference.

BTW: The CV/3D used for Chunky-Copy is not one of the fast ones... even the old Piccolo SD64 is faster.
But still my point is: It is not SLOWER than AGA, so there is no point in using AGA which only few people can use, and which does not run on A1 anymore.

>And I didn't say I don't like people coding for >graphics cards I just said I can understand them -

I cannot... after all don't you want to make it possible for as many people as possible to run your demo ? And that it also runs on future machines ?

>A lot of the old PC DOS-demos work just fine >(Second Reality is a beauty!) and I guess these are >using a technique similar to the one you describe >(using the graphics card as a chunky buffer) since >they had to work on a lot of different cards.

Exactly. And my point is Amiga Demos these days should go this route exactly (I also don't have much love for present-day Demos which are just DivX-Animations rendered with some 3D Package )

>As for hardware availability, AGA is available to any >A1200 or A4000 owner by hooking it up to a TV set - >no need for a 15kHz monitor.

Who hooks a TV to his computer ? Maybe 5 years ago Also you need a fitting cable for this (don't have this either). Most people just say "If it requires AGA I cannot run it".

>(otherwise I'll be very sad > ), >and they will _have_ to use RTG.

Exactly. And people could prepare for this already now

> I'm sure of one thing: The A1 needs something >similar to AMOS or Blitz Basic if any "newbie"

I do not think so. I never liked Basic in any forms.
Well, and if you want functions which can do quick
effects without much coding - use MesaGL, which
will be with OS 4 !!! (That's again the "cheap" trickery with 3D Hardware then, of course).

>coders are going to get interested in it. It will also >need a good 2D pixelpainter and some nice tracker- >sample- and MP3-software if it's going to attract a >full demo group.

As 2D or sample-software is not exactly very CPU-intensive you could use some of the same old 68k software (not DPaint of course, as it does not run on RTG). If I remember right there was some Sound-Package planned for OS 4.

Steffen

[MagicSN]

Hi!

>are BIGGER. Then you have 603, 603e, 604, 604e, G3 >and G4 in many clock
>variations. maybe in the future even more CPUs...

The differences between various PPC CPUs are
much smaller than for 68k CPUs (as PPC is a "true CPU family"). Basically you have one line "faster on Floating Point" and one line "faster on Integer" - sure, you have various numbers of Floating Point units inside and such... but that won't change much the way you code. After all they are all damned fast CPUs, and limiting yourselves to the much faster 68k as the PPC would give you more options sounds
stupid to me

And I do not agree on the "90% optimization" line.
Sure there is a lot of more options for the hardware,
but most hardware just won't make as much of a
difference, if it is then this or that chip...

Only real differences might be

a) Altivec or non-Altivec
b) Certain Features of a 3D Chip (but as most
     demo coders won't use 3D Chips anyways,
     it is not much of an issue...)

I want again to outline my point:

a) Most people these days cannot use AGA anymore (monitors for 15 kHz are rare, and most people
prefer a cheaper 30+ kHz monitor - and I won't
move my Amiga to the TV-Room, having to climb
several Staircases with the Amiga, putting it
up there, also having to change my preferences
setting so I see anything when attaching it to the
TV Set, just to see an AGA Demo... So if a Demo
is AGA-only I will just ignore it. And most people
do the same. So it is in the interest of the demo
coders that they support RTG, or at least both
RTG and AGA. To be serious I do not know a single
person (asides from in this thread) who even
cares about AGA still

b) As to the speed - in most "realistic" tests
RTG is faster (but minor speed differences
are not the issue... the issue is being able
to watch the demo *at all* !!!). I am not
speaking of theoretical maximums, but
real tests. I once wrote such a test myselves
for testing how much speed difference there would be,
and RTG was ALWAYS faster (not on Zorro 2
Boards of course ) Also check out Heretic II
(AGA is VERY slow there, despite the PPC ASM
16 Bit c2p, well 16 Bit on AGA is just slow).
Also for Freespace we even did not release
an AGA version, as when we tested it under
AGA (in Pal Interlaced 640x512) it was just
too slow to be playable - while it runs fine
on GFX Boards in even Software-Rendering.

c) AGA-Demos won't run on the AmigaOne.
Demos without hardware-hacking will.

Steffen Haeuser

[MagicSN]

>From the hardware perspective I also prefer Pegasos >to A1.

What exactly do you prefer there ? The better propaganda ? The two systems are (nearly) the same !!! (Though no OS4 for Pegasos as it seems)

>So I think in the future I will use OS4 for "serious" stuff >and a different system (XBox? PS3?GBA?) for coding.

BTW: That the PS3 will use PPC is in the meanwhile confirmed.

As to your other mail: I don't see anything I said which would be arrogant... as to "imposing my own ideas" - well, I tried several times to make you aware
that not all people CAN use AGA. And that Systems like the AmigaOne CANNOT run AGA Demos also (while RTG Demos could still be compatible). And you come with the same stuff up again and again. Some of the things in your earlier mails (like that one would need to "optimize for different graphics chipsets) were also just bad-researched. And when stating the obvious again and again one CAN get a bit annoyed over time Also I still am waiting on a response concerning the slow speed of AGA on 16 Bit c2p and Highres Displays (Anyways, as I said before - minor speed differences - which depending on situation happen in both directions - don't really matter... what matters is that every Amiga User with a decent Amiga can use the demos, I'd say...

I hope you did not take offense.

Feel free to followup on private email if you want.

Steffen

[MagicSN]

Yes, AGA actually does outperform Z2. (*Z2*, note... )

darkcoder:

Firewire would only be relevant if there would
be Drivers (Also it could get added as
PCI Card to A1 if really needed).

As to the price: OS 4 is included in the price, remember this also.

Interested in AGA ? Sorry if this sounds arrogant,
but this sounds like a terrible waste of time
to me. I explained several times that with AGA
a lot of people cannot use your demos... so any
AGA Support should be optional at best.

And I think if there are two option where one (AGA) does not give ANY major advantage (and it
doesn't !!!), and RTG Support would also make
demos run on

a) more current systems
b) AmigaOne

RTG support should be used (And AGA at most optional).

Steffen