@Kronos

It's not as bad as you think. Have a look at Kalms HAM8 C2P code as an example. The computational overhead of the conversion is masked by the same chip memory write bandwidth. It's true you have to read (and by inference generate in the first place) more source RGB data but that's in your fast memory which likely has much better bandwidth.

This all assumes a typical 040 or 060 setup for which these routines were developed.

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@Karlos

Quote:

Karlos wrote: @Kronos Reading between the lines, I think what Hammer is saying is that if you combine AGA era PC display hardware with a more recent CPU and compare that combination to AGA + PiStorm that the latter gives better results for equivalent titles.

"AGA era" so VLB or early PCI?

I hate to break it to you, but they all had a native 16bit mode and could handle far more bandwidth when used as dumb framebuffer.
They did not need the CPU to encode the data, AGA-HAM did, hence it's worse in such a use case as a dumb framebuffer.

Quote:

Thanks to things like the PiStorm we now have more CPU power

Thanks to PiStorm,UAEGFX and Zorro/PCI/AGP/PCIe cards we now have the power to do it without artifacts or compromises

Sure sometimes it might be fun to do things in a deliberate stupid way and with enough brute force it might even work out, Doesn't change that it is "stupid" and was non viable back when it would have mattered.

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@Kronos

Pah, 16 bit mode. We're talking 18-bit. Almost 24 if you make use of some copper tricks as well.

Affordable PCs in 1992 where I lived had 256 colour (S)VGA from an 18 bit palette. They didn't tend to come with RGB 16 modes. You must have been better off :)

Last edited by Karlos on 22-Jan-2024 at 06:06 PM.

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I'll go a step further. PCs were boring beige boxes in 1992 and every single one I ever encountered at that time only served to confirm that opinion. By 1994 they were such more capable.

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@Karlos

*shrug*

In 1992 you could either buy an A4000 for £££££££££££ or hope to snatch one of the few A1200 that made into store before xmas.

Got mine on Dec24 (no not a gift) and with a 60MB HD it was 1598DM which wasn't a small amount.

I also do remember all the Quake/Doom clones that rendered in a fraction of a 320x200 screen at 10 (unstable)fps while requiring a 030.
An A1200+Blizzard1230 was at least as much as a lowend 486DX2 which would do the real games at 640x480 without breaking a sweat.
That was the moment "AAA" gaming died on the Amiga.

Sure those HAM tricks did "work" but in reality it is and was a blurry mess requiring a 040/060 at a time when anything below Pentium/PCI was on clearance already.

Bottom line, Amiga chipset sucked for 3D and while brute force attempts kinda work they also kinda looked like hot garbage.

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@Kronos

If running Doom was your only concern then sure, a PC was what you needed. If for no other reason that in 1993, it wasn't available for anything else.

I bought by A1200 in 1993, already outclassed by the raw hardware capabilities of PCs that were becoming affordable, but not in a way that I found impressive.

Even then, in 1993, a friend at university with a reasonably specced 386/VGA PC took one look at my base A1200 running WB, protracker and deluxe paint at the same time, screen dragging between them and was floored. He went on to become an avid Amiga user for years afterwards.

Doom came out late that year and the only person we knew that could run it for toffee had a much more expensive 486. Sure, it was the shape of things to come but the idea that everyone had the hardware to run it all of a sudden on release is just the Mandela effect.

Last edited by Karlos on 22-Jan-2024 at 07:29 PM.

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@Karlos

Doom, Quake, Decent (that one I actually played) or Castle Wolfenstein, all the same and all points where £ for £ the Amiga simple could complete anymore.

For me getting the A1200 over the my old A500 was about finally having an HD and mostly going 1.3 to 3.0 that was the big deal.

Sure I kinda could run more colors, didn't care.
Sure I could get a few games that looked a little bit better while still being the same couldn't have cared less.

AGA was a means to an end.
The 020 was a means to an end.
2MB was nice but too little again soon after.
When I got the chance in early 94 to replace it with an A2000+A2630 I took it and was happy (mind you I was running an A2024 anyways).
And when I got my hands on the Picasso2 the chipset was just the scrubby stuff I had to deal with when something went wrong while booting.

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@Kronos

Nobody is claiming AGA or the 020 were ground breaking in 1992. They weren't and there are pages in every forum about how too little to late they were. You know it. I know it. You know I know it and I know you know I know it

However, the capabilities of the average PC are grossly overestimated in a distorted recollection of the era.

Average PCs like average anything do not stand out in your memory, only the exceptional things. The vast majority of PCs that everyday people owned in 1992 were absolutely shit. Many were still grinding away on 286, a significant proportion still didn't have VGA or any audio capabilities at all. Why? Because you are dealing with machines people already had, sometimes for a few years and they generally weren't used for anything that needed better visuals or sound.

You could get a decent spec, brand new SVGA 386 with sound card in 1992. It cost *a lot* more than the A1200 I bought and ran none of the software I wanted to run. So whether or not AGA was inferior to SVGA was hugely irrelevant to me. And in 2024, it still is.

Last edited by Karlos on 22-Jan-2024 at 09:42 PM.

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@Kronos

Quote:

Kronos wrote: AGA was a means to an end. The 020 was a means to an end.

All computing hardware, is a means to and end. Just like all physical tools are a means to and end. They are all 'technology'.

And just like with physical tools, we humans can get carried away because we tend to correlate better technology (means) with better outcomes (ends), so we start coveting the means, and feel superior if we are in the possession of perceived superior means, all while forgetting that correlation is not causation.

The trend data is replete with instances where sub-optimal results are produced despite the presence of superior tech, and equally superior results produced with sub-optimal tech.
Because of 'technique'.

It is often said, the right tool is half the work. That's what the A1200 (OS 3 + apps) was for me in the early-to-mid '90s. And it's what Apple's mac+macOS+apps is for me today.
The same cannot be reasonably said for any PPC hardware intended for AmigaOS 4 and its catalogue of apps.

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@Karlos

Just everyone was still running 286 in 92 everyone was also still running that 1MB A500……

And even in 94 noone was gaming Doom in HAM because it didn‘t look that much better than 256 colors to justify the piss poor performance even on elite priced HW.

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@Kronos

You are missing the point.

Look, it's early 1993. I'm a student. I have a 1MB ECS Amiga. I want to upgrade. Do I buy a new 386 (DX) with SVGA, a terrible FM sound card and a monitor, an atrocious operating system / UX and all with zero compatibility with the software that I want to run, but will run the hot new fps game (badly) that won't appear until late in the year? Or really go nuts and get a 486, which would cost even more and end up being entry level by the end of the year?

Or do I buy a far less expensive A1200 that runs all my existing software, is twice the speed (even before adding fast ram), has improved graphics, plugs straight into the monitor I already have and controls my rather better FM synth over the midi interface I already have?

It's an absolute no brainer. Even if I had a crystal ball and could see Doom would be out by the end of that year, that same PC would barely run it. What's the incentive to buy the PC and not the AGA machine?

This was a true story (tm).

Last edited by Karlos on 23-Jan-2024 at 01:12 PM.

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"So anyway, I bought the PC..."

Didn't happen of the year award.

Doom came out, late 93, coinciding with a relative decrease in the cost of entry level 486 as it ran through numerous clockspeed increases and then the appearance of the Pentium. Graphics and sound capabilities improved, "CDRom/Multimedia" became all the rage.

By the end of 1993, there was no question that things had moved on rapidly. Except for one. None of the new shiny PC stuff ran the software I wanted to use. And so, I expanded the machine, part by part. First with a HD and RAM expansion, then later with one of the first 040 cards. I needed to use a few MS applications by then, but I ran them just fine in shapeshifter.

When DoomAttack was released I was amused to discover it ran at perfectly playable frame rates on AGA on my 040, complete with multichannel sound. Which means that had it have been available in 1993, the A4000/040 could probably have ran it too.

Towards the end of the decade, I had a BPPC/BVPPC, CGX 4.2, OS3.5, network. I still ran shapeshifter for the annoying Uni applications I needed to run, while the rest of my time was messing around in OctaMED, programming and generally enjoying the machine I had. It was only formally retired as my primary machine ~2007.

I just didn't have any PC envy the whole time.

Last edited by Karlos on 23-Jan-2024 at 01:22 PM.

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@Kronos

Quote:

Kronos wrote: @Karlos Quote: Karlos wrote: @Kronos Reading between the lines, I think what Hammer is saying is that if you combine AGA era PC display hardware with a more recent CPU and compare that combination to AGA + PiStorm that the latter gives better results for equivalent titles. "AGA era" so VLB or early PCI? I hate to break it to you, but they all had a native 16bit mode and could handle far more bandwidth when used as dumb framebuffer. They did not need the CPU to encode the data, AGA-HAM did, hence it's worse in such a use case as a dumb framebuffer. Quote: Thanks to things like the PiStorm we now have more CPU power Thanks to PiStorm,UAEGFX and Zorro/PCI/AGP/PCIe cards we now have the power to do it without artifacts or compromises Sure sometimes it might be fun to do things in a deliberate stupid way and with enough brute force it might even work out, Doesn't change that it is "stupid" and was non viable back when it would have mattered.

There are new OCS/AGA games in 2023 and 2024 that can't run on RTG only DraCo 68K.

Last edited by Hammer on 23-Jan-2024 at 03:19 PM.

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@Karlos

Quote:

Karlos wrote: @Hammer Different things are acceptable to different people. Not everyone wants what you or I want. As long as there is the choice, that's what matters.

There are +10,000 AC68080 units in addition to +3400 PiStorm units (via Facebook PiStorm membership estimate).

AGA Southbridge + Emu68 RTG has greater software coverage when compared to RTG-only Draco and Amiga PPC.

Your "choice" is narrower.

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@pixie

Quote:

pixie wrote: @Hammer Somewhere there a Pistorm that connect to a FPGA, it should be somewhat akin to what you describe

PiStorm32 Lite has a small low-cost FPGA Efinix Trion T8Q144C4 (or C3) for PiStorm32 Lite's gateway logic.

Efinix Trion T8Q144C4 has 7,384 logic elements and 125,829 RAM Bits.

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@Kronos

Quote:

Kronos wrote: @Hammer It seems you still don't understand what "dumb framebuffer" means and why the examples shown are ones that do use the chipram as one only with added benefits of the CPU having to do some extra heavy lifting to encode the data.

I do know "dumb framebuffer". Your assumption is wrong.

040/486 era CPU's floating point processing is accelerated by the FPU. FPU's acceleration improved with the classic Pentium and 68060.

Quote:

It doesn't matter how many Amigas had RTG (I'd say about as many as those with a 060) it is just a simple fact that that a proper dumb 16bit framebuffer as offered with most RTG cards would produce a better image with lower CPU usage.

Lower CPU usage... I don't care. Throw 2.2 GHz overclock at the problem.

Genuine ARM and other ARM clones evolve with competitive pacing.

Quote:

Neither of the demos is Quake so we could only guess how these engines do their math and how an 030(+882) or real 060 (since the both use emulation in the videos) would fare.

68060's slow evolution is Motorola/Freescale's problem.

I have TF1260 with 68060 Rev 1 @ 62.5Mhz. I have seen Warp1260 with RTG.

68882's MFLOPS is a joke when compared to 68040 FPU's MFLOPS.

68882's very low MFLOPS (e.g. 1.33 MFLOPS at 50Mhz ) is unstable for games.

68882's FP32 performance wasn't designed like AT&T DSP3210's FP32 33 MFLOPS at 66Mhz.


Quote:

Both run at extremely low res with questionable FPS, most likely due to the 12bit encoding taking up so much time&bandwidth.

My Dell flat screen monitor connected to A1200's RGB is limited up to 60 hz.

Exceeding 60hz is a bonus and a benchmarking use case.

It's well known AGA at 640x480 256 colors 31khz mode is not fast.

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"Dumb Framebuffer" is a bit of a stupid expression anyway. All framebuffers are dumb because they only have one job: being an array of pixel data for display. Some support write masks too, but it's hardly "smart".

If you include the hardware that scans the pixels out as being part of the whole framebuffer concept, then AGA is pretty smart. You've got your built-in beam racing copper that can modify colour registers, etc and you have the quirky ability to hold and modify.

Last edited by Karlos on 23-Jan-2024 at 10:27 PM.

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I’m just not sure where this idea of a dumb framebuffer comes from, I guess we are talking about a image that’s where not hardware accelerated, not in GPU memory.

X11 servers used to be not GPU accelerated, as everything had to be moved over the TCP/IP, then they added DRI support for X11 server, for games, and that helped a lot, X11 up to that point was sluggish.

On Subject of framebuffers, it’s always pretty common on PC to use double buffering or triple buffering, allowing you draw changes into the background image, so you don’t see the changes on screen while they where drawn, but on next frame, it also used reduce tearing, if you can’t render the frame in time. Without it games will look ugly and flicker a lot.

Last edited by NutsAboutAmiga on 24-Jan-2024 at 07:25 PM.
Last edited by NutsAboutAmiga on 24-Jan-2024 at 05:07 PM.

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@NutsAboutAmiga

A framebuffer, at least as far I understand, is either the visible region of the display memory (usually video memory but could also be regular ram in systems with unified memory schemes), or any similar region of memory that can be made visible simply by updating an appropriate hardware register. What might be called a "surface" in some contexts.

I'm less sure about raw pixel data arrays in regular memory not accessible by the display hardware.

People seem to use dumb to imply "only ever written to by the CPU", but I mean that's verb/noun confusion as far as I'm concerned. How you choose to draw into a (directly displayed) framebuffer is what is either smart or dumb. The buffer itself is pretty much neither. You don't refer to any other block of memory as smart or dumb.

Last edited by Karlos on 24-Jan-2024 at 06:56 PM.

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@NutsAboutAmiga

You mean XFree86 on Linux and *BSDs, there were certainly other x11 servers around that had GPU acceleration support, for example I’d be surprised if SGI didn’t have acceleration for their Reality Engine series.

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