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classic battle atari 8bit vs commodore 64


phuzaxeman

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Maybe a bad example, but I always loved the music in this game.

 

Actually, this is a very interesting example:

- interlace

- road covers full screen height (for the hills)

 

IIRC, interlace on CRT looks darker, but certainly nowhere near the same as on LCD. Besides, after few minutes, brain gets used to it anyway.

 

It's an interesting cheat, one I would most certainly write off right off the bat...

 

It's funnier to know that particular this effect is a standard effect using ANTIC on the Atari and some LMS programming.

Racing the beam in that range and to change some bytes on the flow to suggest that "more is going on" isn't very CPU consuming.

True, changing LMS is just few cycles. Unfortunately, LMS implies the texture's perspective is precomputed, e.g. each frame of each scanline is stored in RAM. You would need ~0.5 MB of RAM for all the frames of the texture I'm working with right now (160x40), while the routine I'm working on now would work even on sub-64 KB Ataris.

 

I'm more interested in a generic solution, for an in-game scenario (or a great cut-scene). You simply reuse the same routine. If you updated the texture at run-time procedurally, you could easily show 10 different textures over 10 seconds (creating new texture each second), even though at any time there'd be just 1 texture in RAM. I don't think I've seen that particular effect on 6502.

 

Also, when you're computing it brute-force, you must forget racing the beam. STA WSYNC over whole screen (or half) kills what little remains after the Antic robbery...

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Actually, this is a very interesting example:

- interlace

- road covers full screen height (for the hills)

- No Interlace just blank lines thus:

-50% of the screen height used.

 

 

True, changing LMS is just few cycles. Unfortunately, LMS implies the texture's perspective is precomputed, e.g. each frame of each scanline is stored in RAM. You would need ~0.5 MB of RAM for all the frames of the texture I'm working with right now (160x40), while the routine I'm working on now would work even on sub-64 KB Ataris.

Come on , get the point. ;)

LMS comes almost for free. Even on the C64 there ARE repetitive patterns. They were slightly changed to have more variations to show to the viewer which could be done while racing the beam in that range on the Atari.

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- No Interlace just blank lines thus:

-50% of the screen height used.

Yeah, sorry - I didn't mean 50i/60i video mode, I meant interlaced lines.

Empty lines on A800 would bring about 4,800 cycles per frame in 160x192, IIRC. That's quite substantial. If your core framerate was 15 fps (4 jiffies), you'd suddenly gain 4x4,800 = 19,200c. Damn!

 

 

Come on , get the point. ;)

LMS comes almost for free. Even on the C64 there ARE repetitive patterns.

Yeah, but if they're using LMS alternative on C64 (unknown to me), then they are merely wasting memory, as the same memory (for each scanline ) could have each pixel unique, instead of 10x repeat,

But, like I said earlier, that demo has about a dozen scenes, it all had to fit into 64 KB, so it's surely just a content compromise (e.g. preference to have more scenes/effects, rather than higher res textures).

 

 

...which could be done while racing the beam in that range on the Atari.

Of course, if we throw memory at the problem, then it's not really a challenge on Atari, now is it ? You precompute scanlines at loading time, and then just change 2 Bytes for those few affected scanlines. Literally, ~95% of the frame time would be still available for other effects/music/etc. It's basically a ~free effect then. Like, why even bother at that point :) ?

 

 

We can, however, do much better on Atari. We can do real-time texel look-up much faster, thanks to 1.79 MHz.

 

 

The 6502 texturing routine I've been working on last few days, I've been testing with texture 160x40 - e.g. as high res as possible in 160x96 (each on-screen pixel corresponds to one texel, when closest to camera). First version took 411,552 cycles (3.5 fps), but after over a dozen refactoring attempts, today it takes just 71,690 cycles (20.2 fps).

 

The sweet spot seems to be around 112x40, which takes 48,594 cycles (29.83 fps). I'm using 160x96 screen resolution (assuming 24,160 cycles available for CPU after Antic was fed).

 

 

I can't wait to get LMS going, and mirror (for free) the bottom half of the screen into the top half, and get full-screen tunnel with HiRes texture. Now that's something poor C64 cannot do at more than ~half framerate :)

Or 25% framerate - depending if C64 has LMS or not (no idea, haven't coded with C64) :)

 

Since performance is linear to the number of pixels, using interlace would halve those numbers. If, instead of computing mirroring in the middle of scanline, I was doing simple repeat, those numbers could go down even further, as I could merge 2 pipeline stages into one, avoiding multiple RAM accesses (per pixel). And there's always self-modifying code (for inner loops) and loop unrolling if we need further performance.

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Yeah, but if they're using LMS alternative on C64 (unknown to me), then they are merely wasting memory, as the same memory (for each scanline ) could have each pixel unique, instead of 10x repeat,

But, like I said earlier, that demo has about a dozen scenes, it all had to fit into 64 KB, so it's surely just a content compromise (e.g. preference to have more scenes/effects, rather than higher res textures).

Seems, you've got rick rolled there ;)

Some people say it is a good thing to have POKEY doing the loading sounds. But that keeps the possibility of "Trackmos" limited. The C64 can load data in the background, SID is playing it's tune.

The interesing stuff there is that all that transitions in such C64 demos do their part very cleverly. Here a bit there a bit.... and after the loading is done, the main part of the "demo" gets running. Then things turn to little movement, for doing the transitions for the next demo part ... and so on.

 

 

 

And, btw. This "Eliminator" game don't need those black scanlines on the Atari. It's named "Antic D" ;)

Edited by emkay
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Seems, you've got rick rolled there ;)

Some people say it is a good thing to have POKEY doing the loading sounds. But that keeps the possibility of "Trackmos" limited. The C64 can load data in the background, SID is playing it's tune.

The interesing stuff there is that all that transitions in such C64 demos do their part very cleverly. Here a bit there a bit.... and after the loading is done, the main part of the "demo" gets running. Then things turn to little movement, for doing the transitions for the next demo part ... and so on.

 

 

 

And, btw. This "Eliminator" game don't need those black scanlines on the Atari. It's named "Antic D" ;)

I don't follow - rickrolled ? How?

 

Antic D is 160x96, which is what I'm using. But the feeling and "look" is different between the two modes, even if they ultimately have almost same performance characteristics (though, the 96 blank lines in DL will consume some additional (if, small) bandwidth over 60 frames).

 

From my very ancient experiments with interlaced gfx, I recall that sometimes interlaced hires looks better.

 

Ideally, this would be a choice left to the player, as from coder's perspective, very little needs to be changed (just DL).

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@VladR

 

Here "again" the "Basicdemo" video

 

 

People who don't know about the Atari, won't recognize it.

The Demo is build upon features that cost very low CPU time, won't interfere Sounds or loading from Disk. The main cause for me to show it is the following:

 

Most of those C64 Demos use , what could be named "Multitasking" . Everything that used very low "system resources" is used to show something, while other things get prepared.

I know, people need a higher achievement on the Atari to understand it. But, let me explain that the Demo is created in Atari BASIC, which is VERY slow. AND it does 2 things at the same time.

Or should I write it in other words?

Just like "C64 programming is 40 years ahead of Atari 8-Bit programming" . There are some exceptions, but there is nothing on the Atari in demo coding as advanced as C64 demo coding.

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Yes, of course - concurrent processing - that's the basic premise of demoscene. I understand that - I just don't understand why are you bringing it up here.

 

While an effect that consumes 25% of CPU is being rendered, the remaining 75% are devoted to gradual precalc of next effect.

 

Which is exactly why, suddenly a simple scroller starts dropping frames, because the code simply processes fixed number of loop iterations each frame, but the load (in terms of cycles) is slightly different.

 

 

So, your point is what exactly ? That not all Atari demos have smooth transitions between the consecutive effects ? That's up to the coder, if he wants to burn more time to do it that way. That doesn't have anything to do with the machine's strengths - there's just one 6502 in both C64 and Atari.

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So, your point is what exactly ? That not all Atari demos have smooth transitions between the consecutive effects ? That's up to the coder, if he wants to burn more time to do it that way. That doesn't have anything to do with the machine's strengths - there's just one 6502 in both C64 and Atari.

You'll never get my point. I've got that.

 

C64 has a lot advantages , the Atari has own advantages . C64 is coded to the last edge of the possible. The Atari is coded to chase the C64's features . There are exceptions. That's all.

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Yeah, there's no argument about how huge the C64 scene is, that's for sure.

 

Which was the reason why I asked the question, as it gets real ugly real fast, trying to browse the C64 demoscene on YT...

 

BTW, would you happen to know how much more C64 sold [compared to Atari] ?

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BTW, would you happen to know how much more C64 sold [compared to Atari] ?

That doesn't really matter. The main problem here is that the most coders on the Atari do their part to chase C64 in features and code.

If the same amount of coders had done coding the A8 in color presentation and Ego view stuff, things were more balanced.

Edited by emkay
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I don't go and see what is happening in C-64land all that often - but I do wonder are there any demos that are like Xanth Park demos - or anything that can rival the Atari Robot and spaceship demo (I forget the name of the guy who worked on this).

Most of the C-64 demos I have come across - which are not that many - don't do anything interesting?

 

I could say that as well about the many other A8-bit demos I have seen - forgettable.

That they do the same kind of stuff - no matter how well done and complicated it may be.

 

I would like to see the one theme running through a long demo - so that it feels connected - and that it is a viewing experience to go through - instead of things disjointed - with text that says nothing much at all.

 

The one C-64 demo that totally impressed me - and almost makes up for the lack of other such demos - is the SNES graphics of The Legend of Zelda running along very nicely. If someone can list and provide URLs whatever other noteworthy C-64 demos/etc - I would like to see them?

 

Has anyone done a Youtube video of 'Let's Compare..' the greatest demos from all the home computers of the 80s' era? I just hope it doesn't bore me to death - like looking at a lot of ST vs Amiga demos?

 

Harvey

Edited by kiwilove
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Yeah, there's no argument about how huge the C64 scene is, that's for sure.

 

Which was the reason why I asked the question, as it gets real ugly real fast, trying to browse the C64 demoscene on YT...

 

BTW, would you happen to know how much more C64 sold [compared to Atari] ?

 

Well,

 

I do not know for sure, but various sources I have read say something like that:

 

- Atari 8Bit approx. 2 millions vs. C64 approx. 20 millions

- Atari 8Bit approx. 2.5 millions vs. C64 approx. 25 millions

- Atari 8Bit approx. 3 millions vs. C64 approx. 30 millions

 

So the C64 sold approx. ten times more than the Atari 8Bit did.

Main reason in the beginning was the cheap price of the C64 vs. expensive XL machines (and the videogame crash and as a result Warner selling Atari in 1984; here in Germany everyone wrote or said that Atari went bankrupt; they even said it to me, when I bought my 800XL and told me it would be better and safer to buy a C64). Later with the large user base and prices comparable, the C64 still sold more, because more programmers/developers/firms/etc. developed and programmed for this large user base and as a result many more programs were available on the C64 that did and still do not exist for the XL/XE machines. So at first it was the cheap hardware, later the huge library of software.

 

Nowadays we Atarians are lucky and can be very happy that dozens of programs get converted and ported from Spectrum, BBC and C64 and several conversions are even better (and/or faster) on the A8 than their originals.

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I don't go and see what is happening in C-64land all that often - but I do wonder are there any demos that are like Xanth Park demos - or anything that can rival the Atari Robot and spaceship demo (I forget the name of the guy who worked on this).

 

Xanth demos Fuji Boink, Amiga Boink, Swan demo - Michael Park.

Atari Robot and Spaceship demo - Jim St. Louis, Russ Karas ?

 

(I always thought M.Park did them all, looks like I was wrong.)

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Well,

 

I do not know for sure, but various sources I have read say something like that:

 

- Atari 8Bit approx. 2 millions vs. C64 approx. 20 millions

- Atari 8Bit approx. 2.5 millions vs. C64 approx. 25 millions

- Atari 8Bit approx. 3 millions vs. C64 approx. 30 millions

 

 

 

Probably closer to 12-13 million units ( based on known serial numbers ) if you don't count the 5 million c128 units sold. In interviews Tramiel says he sold between 300,000 - 500,000 a month but he wasn't really there long enough to know the exact numbers. In other interviews, he says between 22 and 30 million units total.

 

Jack came up with the name Commodore after he saw an Opal Commodore make a short stop in front of his cab in Germany, Leonard says that story is impossible because the model was introduced in 1967 but Commodore was founded in 1954. Jack also said that he paid Bill Gates $25,000 for the V2 basic but in one of Leonard's interviews, he says that they paid a one time fee of $50,000 for the basic. I guess the point I'm making here is people's memories can also be fallible especially after so many years.

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I see I wasn't the only one confused by the numbers [and their discrepancy] I looked up previously.

 

But, how on earth can there be a confusion ? Wasn't it a publicly traded company ? Those need to release the precise numbers, get audited, etc.

 

 

Those also need to be very clear on numbers manufactured vs shipped vs actually sold.

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The company was liquidated so nobody really knows what the figures were. The numbers we hear of today come from fans, ex employees & computer historians. Which explains all of the confusion.

Wait, was there a different version of Capitalism in U.K. and U.S. just few decades ago ? Granted, the ex-communist clusterfu*kistan I grew up in, made sure we were shielded from things like stocks, options, ROI and dividends. Though, in the last 5th year of my university, we had a subject covering stock market, which literally, was the only official subject matter that could be obtained without the risk of ending on a watch list plus a permanent mark on your police report.

 

Surely, though, the people who invested in publicly traded companies were entitled to quarterly reports on company's well-being ? That stock market thingy is well over a century old, so ?

 

In early '90s, when the CNN could be officially broadcast at home, their financial segment looked (IIRC) very similar to present-day financial segment. It's not a rocket science after all - either your stock goes up or your investment goes belly up

 

 

 

Unless, one of the two happened:

1. Atari wasn't a publicly traded company

2. Quarterly reports didn't need to have those numbers (ridiculous, but very remotely probable)

 

 

Given the predominantly American population of AtariAge, surely there's couple dozen people here who can clear this up ? And no, I most certainly do not intend to look it up on wiki or other sites serving their particular agenda.

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Given the predominantly American population of AtariAge, surely there's couple dozen people here who can clear this up ? And no, I most certainly do not intend to look it up on wiki or other sites serving their particular agenda.

 

So Wikipedia is skewed, but posters on forums don't have any particular agenda? S'funny :)

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So Wikipedia is skewed, but posters on forums don't have any particular agenda? S'funny :)

This might be shocking to you, but from years of browsing these forums, one eventually notices personal agendas.

 

Just so we don't have to go far for concrete examples, surely you wouldn't accuse emKay of being pro-Atari, now would you ?

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During years of browsing other forums I have noticed plenty of people with agendas. In fact, we all have them, to some extent - me included. I don't see why things would be any different here. So, in case you missed my point in the first place (it seems so) I find it funny that somebody would wag their finger in direction of Wikipedia (edited by internet users) and "other sites" and at the same time trust the same "internet users" elsewhere.

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Ok, I wasn't exp!icit, as I thought it's implied, automatically.

 

But as soon as you read somebody 's response, you filter it based on this person's vocabulary and personal preferences you are aware of.

 

 

You do not have that background info on wiki/news site. Hence my preference.

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Well,

 

I do not know for sure, but various sources I have read say something like that:

 

- Atari 8Bit approx. 2 millions vs. C64 approx. 20 millions

- Atari 8Bit approx. 2.5 millions vs. C64 approx. 25 millions

- Atari 8Bit approx. 3 millions vs. C64 approx. 30 millions

 

So the C64 sold approx. ten times more than the Atari 8Bit did.

Main reason in the beginning was the cheap price of the C64 vs. expensive XL machines (and the videogame crash and as a result Warner selling Atari in 1984; here in Germany everyone wrote or said that Atari went bankrupt; they even said it to me, when I bought my 800XL and told me it would be better and safer to buy a C64). Later with the large user base and prices comparable, the C64 still sold more, because more programmers/developers/firms/etc. developed and programmed for this large user base and as a result many more programs were available on the C64 that did and still do not exist for the XL/XE machines. So at first it was the cheap hardware, later the huge library of software.

 

Nowadays we Atarians are lucky and can be very happy that dozens of programs get converted and ported from Spectrum, BBC and C64 and several conversions are even better (and/or faster) on the A8 than their originals.

Some people are comparing game titles on the Atari 8-bit that was available years before the Commodore 64 version when more experience programmers ported that title. However, there were some Commodore 64 titles that were very poor ports, did not look play or look as good as the Atari 8-bit. Depends on what the game needs to display what is going on, and how good the programmer did the port. I am sure some programmers can take a port now and make it as good on the other platform.

 

By the time Jack Tramiel took Atari over and made the XE series, the Atari 8-bit platform as obsolete because the 16K systems and IBM PCs were on the market. No way it was going to catch up to catch up to Commodore 64 by then. Plus Atari did not jump on releasing new software for the XE series right away. Like programs that utilize the 130XE extra RAM, did not release new games until the XEGS. Sucks when Jack Tramiel fired most of the programmers and canceled games in progress.

 

There seems to be a lot of comparison of demo's on here, still pictures, but how about some software people use. Games in action with the YouTube videos.

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Jack came up with the name Commodore after he saw an Opal Commodore make a short stop in front of his cab in Germany, Leonard says that story is impossible because the model was introduced in 1967 but Commodore was founded in 1954.

 

I think most people today believe it was a Hudson Commodore, and that it probably happened in Canada or possibly the US which is where Tramiel was residing in the early-mid 1950's. There is a closed FB group about Commodore history where a lot of valuable documents have been posted lately about the businesses Tramiel and his colleague were involved in before Commodore was formed.

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