Atari v Commodore

[atariksi]

DLIs are set up for the entire display list by adding 128 to whichever mode line you want them. For C64, you have to keep rewriting to the $D012 register to trigger off the next raster line interrupt so that's more overhead.

Which can be an advantage or a disadvantage. In the case of sprite multiplexing for example it's clearly an advantage since there IRQ positions change all the time according to sprite positions.

 

But C64 is not doing the work of a DLI-- you are picking some example where IRQs work better. Atari also has IRQs. Let's look at your general case raster interrupt to set some hardware register during hblanking. A bare bone DLI on Atari involves 7 cycles through vectoring through [65530] and a RTI (6 cycles) and one bit from DL instruction so that's 13.125 cycles/DLI for any number of DLIs in a frame. On Atari 400/800 and for allowing checking for VBIs, it's an additional 11 cycles. Now let's see your bare bones raster interrupt and the cycle breakdown.

[Shawn Jefferson]

They work great for many things. Sorry, you missed out on many good things. You have only stated your subjective views. There are flexibile modes for 16+ colors and there are also more restricted modes that require more complexity to get more colors.

 

True, I think the use of the 80x192 GTIA modes are very limited in their application, and that's just my opinion. I'd trade them in a heartbeat for 4 more PMG, or better yet, 8 32x32 multi-color sprites. Same with many of the other graphics modes on the Atari 8-bit. I'd keep ANTIC modes 2, 4, E and F.

 

You (probably) aren't going to use GTIA modes to port the great later C64 games mentioned here.

 

If you are an assembly language programmer, it doesn't matter where you put the window as long as it doesn't overlap the I/O area (which it doesn't). For BASIC, that's the only place to put the 16K window where you can use it in BASIC. As far as size of Window goes, you need more than 8K if you ever do overscanned GTIA modes or graphics 8 or even 192*200*4.

 

I do see your point here... if it was only 8k, it wouldn't work for an overscanned mode F screen. Still, I think the memory bank window is very large and inflexible, and you do have to carefully plan where you put everything to use it-but I guess that's the reality of programming these machines anyhow. You are either dealing with the banking window, the cartridge bank window, or the under the OS window, and then the limitations around where fonts, screen, dlist and PMG can be placed in memory as well.

 

>It's highly subjective.

 

Nope. It's better to have a boot option and WSYNC than not have them. That increases flexibility. You can always choose NOT to boot and NOT to use WSYNC. More choices means more flexibility.

 

I can't agree with you here. Users will have their own opinions on what "features" of the machine provide more flexibility. I was trying to point out that both have their good features, their limitations and advantages.

 

>C64 users may wonder why we need to BOOT a DOS to do anything.

 

That code I posted allows you to boot into BASIC w/o DOS with the machine language code preloaded and running.

 

How does the machine language code get preloaded?

 

Screen-high sprites more helpful with overlays.

 

I think that's debatable. Depending on what you mean as "overlays". If you are thinking of creating more colorful moving objects on the screen, like most games require, the C64 style sprites are more helpful, IMO. If you are thinking of overlaying static backgrounds to gain more color, sure, there's the Atari method (and the GRAF register stuffing technique too!)

[Rybags]

C64 users may wonder why we need to BOOT a DOS to do anything.

 

Practically every computer ever made does it that way. 99% of the world's computer users could turn that around and say "Why did Commodore do it that way?"

[PeteD]

DLIs are set up for the entire display list by adding 128 to whichever mode line you want them. For C64, you have to keep rewriting to the $D012 register to trigger off the next raster line interrupt so that's more overhead.

Which can be an advantage or a disadvantage. In the case of sprite multiplexing for example it's clearly an advantage since there IRQ positions change all the time according to sprite positions.

 

But C64 is not doing the work of a DLI-- you are picking some example where IRQs work better. Atari also has IRQs. Let's look at your general case raster interrupt to set some hardware register during hblanking. A bare bone DLI on Atari involves 7 cycles through vectoring through [65530] and a RTI (6 cycles) and one bit from DL instruction so that's 13.125 cycles/DLI for any number of DLIs in a frame. On Atari 400/800 and for allowing checking for VBIs, it's an additional 11 cycles. Now let's see your bare bones raster interrupt and the cycle breakdown.

 

It being a 6502 as well it's going to be pretty much the same eg do you need to push/pop anything, an rti at the end etc. I don't think anyone is arguing about the fact that a DLI, for what it does is slightly faster than a raster interrupt on C64, what I think is being said (at least what point I keep trying to make) is that for 6 cycles extra you can have an interrupt on any scanline you want. I don't know of too many games that use more than say 10 interrupts on c64. Maybe a vblank, one to split the screen mode/scroll position for a panel, a multiplexer or a few colour changes. So for the loss of 60 cycles per frame the C64 coder has access to scanline exact interrupts. To do this on A8 I'm having to use a timer and normally there wouldn't be a problem with that, they get used all the time on C64 as well, but on A8 it's likely to screw with any music I use unless the music is designed specifically for my game.

 

I suppose if a game is designed for A8 knowing the limitation of DLIs positioning it's not a problem but I can think of plenty of uses for a more scanline based approach and certainly porting C64 stuff to A8 coders will immediately come across problems, I know I have.

 

 

Pete

[Rockford]

...

C-64 on the top again. The disproportion in quality makes it so humiliating.... I think that words are needless here.

...

"humiliating" is really not needed there...

If you want people to take you seriouslly stay away from such phrases...

 

English is a beautiful language, there are so many more words you could use...

 

p.s. Never seen that game, really does look better on C64...

 

Popmilo, your posts and words are rational and reasonable to me, so all I can say you are right here. Probably I have gone too far with teasing and I am sorry for that. Anyway, soon I am going to prove that C-64 can handle iso 3D games better than Atari

 

Your reasoning was already refuted and rather than reply to that you go on with your same reasoning. You have NOT proven Atari is inferior with examples that show off wider sprites or color RAM of 40*25 of 16 colors force fitted to every object on earth. You need to find some other hardware aspect to show what C64 hardware can do. What goes into building a particular game is not necessarily what the hardware matches up with. You neither stick to original topic nor the general topic of "Atari vs. Commodore."

 

Funny, I don't remember you saying anything like that when Allas was doing exactly the same thing. Maybe because he was showing (example after example) games that look better on Atari ? You know, it is called a double morality

[Irgendwer]

...

Anyway, soon I am going to prove that C-64 can handle iso 3D games better than Atari

 

Like 'The Scrolls of Abadon'?

[PeteD]

Scrolls of Abbadon isn't really full isometric, rather an isometric viewpoint. Like Zaxxon, Havoc etc it's really just a scroll routine (I think Abbadon scrolls?) and sprite movement based on (usually) 2:1 rather than 1:1 (or 1:0 0:1) movement. Something like Head over Heels or the Ultimate games where objects move behind/mask with the background is more "real" isometric. That's usually where the Atari would win out because all that masking and/or world drawing is a cpu intensive thing. Last Ninja for example is doing masking on the C64 but the only real reason there's no LN on Atari is it's harder to do all the colours used on the C64 version, not impossible I may add, just harder. They could of course have done it mono like the Spectrum version, but who wants that?

 

 

Pete

Edited September 4, 2009 by PeteD

[frenchman]

Mastertronic, a UK mass-producing cheap games company.

But sometimes they get it right:

Mastertronic, a UK mass-producing cheap games company.

But sometimes they get it right:

Amaurote Atari 8-bit:

isometric view, excellent playabilty

 

Amaurote C64:

top down view because C64 couldn't handle the isometric and totally unplayable. In Rockfords words: The disproportion in quality makes it so humiliating.... I think that words are needless here.

 

This example has been already shown, so try harder please and find something new.

 

 

It's so good it's allowed to be shown twice.

 

Anyway, here's you, you look and play horrible on C64 AND A8, only you manage to do so (Attention, these two games are NOT Boulder Dash):

Rockford C64

Rockford A8

again, both from Mastertronic.

 

But here's another beauty from Mastertronic/Bulldog:

Invasion C64:

Looks nasty, plays even more nasty. In Rockfords words: The disproportion in quality makes it so humiliating.... I think that words are needless here.

 

Invasion A8:

better colour palette, smoother scrolling, far better game play

Edited September 4, 2009 by frenchman

[emkay]

64 couldn't handle the isometric?

 

doubtful. there are quite a few c64 iso games that started life on the spectrum. they were executed well enough, ...

 

There were many "tricks" used to have the games running.

One example was given in this thread before:

Several objects that move at the same time in each version A8 and Speccy, move interleaved on the C64, to save cpu time.

In Amaurote, this technique is not possible when trying to keep the gameplay most correct.

[TMR]

But C64 is not doing the work of a DLI-- you are picking some example where IRQs work better.

 

That's pretty much the point, you have a little more housekeeping to do and nobody from either camp has denied that, but those extra cycles go towards a significant gain in flexibility and there are more cases where raster interrupts are favourable to (and indeed more efficient than) display list interrupts than the other way around. If you want a split every four scanlines over a character-based screen (a real world example at the moment, because my currently back-burnered A8 project could do with exactly that[1]) that's no problem with a raster interrupt but the DLI either needs to consume significant amounts of resources in wait loops or call in another interrupt to deal with the bits it can't do.

 

[1] The project isn't back-burnered because of the splits every for scanlines thing, it's on hold because i've got a C64 game to complete for around a week today... come to think of it, i'd better go! =-)

[TMR]

Several objects that move at the same time in each version A8 and Speccy, move interleaved on the C64, to save cpu time.

In Amaurote, this technique is not possible when trying to keep the gameplay most correct.

 

Doesn't matter though, because if you read what Ste Pickford said they didn't actually attempt to put it into the C64 so we can apply frenchman's logic; if nobody tried, it's possible.

[frenchman]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

[TMR]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

 

To be honest, i was being a tad sarky there; in this case there are other games have done isometric 3D on the C64 to similar specifications, meaning it's proven to a reasonable degree by those if not specifically by a working iso 3D version of [a]Amaurote[/b] - that's a different matter to using the argument in a more general sense as you did when i picked you up on it and the David Crane analogy doesn't work in the latter case because as i said there's nobody taking the "i've done it" role.

[frenchman]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

 

To be honest, i was being a tad sarky there; in this case there are other games have done isometric 3D on the C64 to similar specifications, meaning it's proven to a reasonable degree by those if not specifically by a working iso 3D version of [a]Amaurote[/b] - that's a different matter to using the argument in a more general sense as you did when i picked you up on it and the David Crane analogy doesn't work in the latter case because as i said there's nobody taking the "i've done it" role.

 

 

There you go, that backfired didn't it. But that's the trouble with the C64er's, always taking the mick (trying hard anyway)....but don't know much.

Edited September 4, 2009 by frenchman

[PeteD]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

 

Not wanting to get embroiled in this one again but that logic only goes so far. There are finite possibilities based solely on known facts which can't change such as cpu speed, hardware etc, presuming things are possible over those finites is breaking the laws of physics

 

Pete

[PeteD]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

 

To be honest, i was being a tad sarky there; in this case there are other games have done isometric 3D on the C64 to similar specifications, meaning it's proven to a reasonable degree by those if not specifically by a working iso 3D version of [a]Amaurote[/b] - that's a different matter to using the argument in a more general sense as you did when i picked you up on it and the David Crane analogy doesn't work in the latter case because as i said there's nobody taking the "i've done it" role.

 

 

There you go, that backfired didn't it. But that's the trouble with the C64er's, always taking the mick (trying hard anyway)....but don't know much.

 

And another blanket statement seemingly designed to annoy anyone who might call themself a C64er like myself. This is why I got into an argument the other night you have no idea how much I know or TMR knows but we don't try to tell you that you know less than anyone. And Atarianwhatever still thinks I'm the rude one

 

Pete

[+Philsan]

For me it's not a problem to admit that C64 in some respects is superior, in particular sprites capabilities very useful for games.

But C64 came out THREE YEAR LATER, an eternity.

The fact that A8 is still superior in some respects it's awesome.

Edited September 4, 2009 by Philsan

[STE'86]

where do u keep pulling these comparison games from? "totally shit games 'r' us?"

 

either of those invasion games look like the game has crashed on screen and corrupted the graphics.

 

its not really proving anything that a crap looking atari game is marginally superior looking than a REALLY crap looking 64 game now is it?

 

and if scraping the bottom of the barrel to find such games is the only recourse to proving an atari game can look better than a 64 one then realistically u are only proving the opposite.

 

so lets just let the comparisons of crap games fade away i think

 

Steve

Edited September 4, 2009 by STE'86

[PeteD]

where do u keep pulling these comparison games from? "totally shit games 'r' us?"

 

either of those invasion games look like the game has crashed on screen and corrupted the graphics.

 

 

 

ROFL

[atariksi]

...

C-64 on the top again. The disproportion in quality makes it so humiliating.... I think that words are needless here.

...

"humiliating" is really not needed there...

If you want people to take you seriouslly stay away from such phrases...

 

English is a beautiful language, there are so many more words you could use...

 

p.s. Never seen that game, really does look better on C64...

 

Popmilo, your posts and words are rational and reasonable to me, so all I can say you are right here. Probably I have gone too far with teasing and I am sorry for that. Anyway, soon I am going to prove that C-64 can handle iso 3D games better than Atari

 

Your reasoning was already refuted and rather than reply to that you go on with your same reasoning. You have NOT proven Atari is inferior with examples that show off wider sprites or color RAM of 40*25 of 16 colors force fitted to every object on earth. You need to find some other hardware aspect to show what C64 hardware can do. What goes into building a particular game is not necessarily what the hardware matches up with. You neither stick to original topic nor the general topic of "Atari vs. Commodore."

 

Funny, I don't remember you saying anything like that when Allas was doing exactly the same thing. Maybe because he was showing (example after example) games that look better on Atari ? You know, it is called a double morality

 

First of all, I don't think you even understood what I wrote above (re-read). Secondly, Allas has a right to do that in this topic as per original poster's request. Thirdly, I am arguing against the conclusions that you are drawing from your examples. Fourthly, ... I'll stop for now until you get the first three statements.

[atariksi]

They work great for many things. Sorry, you missed out on many good things. You have only stated your subjective views. There are flexibile modes for 16+ colors and there are also more restricted modes that require more complexity to get more colors.

 

True, I think the use of the 80x192 GTIA modes are very limited in their application, and that's just my opinion. I'd trade them in a heartbeat for 4 more PMG, or better yet, 8 32x32 multi-color sprites. Same with many of the other graphics modes on the Atari 8-bit. I'd keep ANTIC modes 2, 4, E and F.

...

No need to trade them. They could have had more sprites on A8 w/o trading the graphics modes (38% of PMBase memory is unused). GTIA modes are flexibile and linear although not as resolute w/o interlacing or other complex procedures. You want to keep all modes when enhancing the capabilities for backward compatibility. Look at modern VGA cards-- they still retained the CGA/EGA compatibility. And believe me, lower resolution modes are faster if rendered by hardware than software. You also forget that even the C64 w/color ram is restricted. It's hard to draw a simple line with one of 16 colors and move it around. The way to look at it is that it's a extremely lossy version of vector quantization where the vectors are 4*8 (or 8* and the colors are also restricted in this highly quantized space-color continuum.

 

>You (probably) aren't going to use GTIA modes to port the great later C64 games mentioned here.

 

There are drawbacks in porting graphics from a machine that has a different method of dealing with them than an Atari and especially colors from a more restricted color space.

 

>I do see your point here... if it was only 8k, it wouldn't work for an overscanned mode F screen. Still, I think the memory bank window is very large and inflexible, and you do have to carefully plan where you put everything to use it-but I guess that's the reality of programming these machines anyhow. You are either dealing with the banking window, the cartridge bank window, or the under the OS window, and then the limitations around where fonts, screen, dlist and PMG can be placed in memory as well.

 

It's not a major concern as majority of applications/games don't even do banking.

 

>>Nope. It's better to have a boot option and WSYNC than not have them. That increases flexibility. You can always choose NOT to boot and NOT to use WSYNC. More choices means more flexibility.

 

>I can't agree with you here. Users will have their own opinions on what "features" of the machine provide more flexibility. I was trying to point out that both have their good features, their limitations and advantages.

 

No, for boot and WSYNC, they don't exist on C64. Whatever software algorithms you use for WSYNC simulation on C64 can be done on A8 as well. So it's better to have both options than one.

 

>>That code I posted allows you to boot into BASIC w/o DOS with the machine language code preloaded and running.

 

>How does the machine language code get preloaded?

 

You don't have to load DOS from 1792 upwards if you need the memory space or want to speed up your boot time. You can boot up just a sector or two that contains the code you need.

 

>>Screen-high sprites more helpful with overlays.

 

>I think that's debatable. Depending on what you mean as "overlays". If you are thinking of creating more colorful moving objects on the screen, like most games require, the C64 style sprites are more helpful, IMO. If you are thinking of overlaying static backgrounds to gain more color, sure, there's the Atari method (and the GRAF register stuffing technique too!)

 

The code I posted is an example of what I meant by overlay. You have the whole screen covered with sprites and no CPU involved. Of course, you can do a lot more with the CPU involved. Vertical multiplexing is much easier with taller sprites.

[frenchman]

where do u keep pulling these comparison games from? "totally shit games 'r' us?"

 

either of those invasion games look like the game has crashed on screen and corrupted the graphics.

 

Steve

 

 

Great isn't it, Mastertronic, UKs top selling software house during the 80s/early90s.

[TMR]

To be honest, i was being a tad sarky there

 

There you go, that backfired didn't it.

 

It would only have backfired if your logic extended to cover the situation i was talking about and, as i explained, it doesn't. As sarcasm goes it was possibly a little too subtle, that's all.

 

But that's the trouble with the C64er's, always taking the mick (trying hard anyway)....but don't know much.

 

Sorry, but you really don't seem to have the slightest idea of how much i do or don't know... if i got some of what i've said here into print in Retro Gamer, would that somehow validate it for you like the David Crane quote in your broken analogy?

 

Whilst we're here talking about what people do and don't know, what's your background to be able to judge the claims made by the programmers in this thread?

[PeteD]

All this comparison stuff is getting a bit silly really. If one side shows a better game the other side says they aren't allowed to use that as an example for some reason like the C64 is using it's hardware or has colour attributes or some such. Basically they both have 6502 (compatible) chips, one of which is faster than the other. There, Atari wins Only it isn't a cut and dry as that if you're willing to compare both machines INCLUDING their hardware. Doesn't matter which came first or if the one that came first didn't get GTIA till later in its life. If you aren't willing to compare like for like games then what's the point of the whole thread? Of course people are going to extremes to prove points and there are always going to be dire games around. Some games have nothing to do with each other on different platforms.

 

imho both machines are decent enough to run games on, especially for their time back in the 80s. The Atari's games tend to be of a lower quality because the coders couldn't be bothered (or just didn't know how to) exploring other possibilities for doing things the C64 can do, basically (I would imagine) because the monetary reward just wasnt there by the time the C64/Spectrum/CPC had come into power. Those were the days of a game in a month or so. I've already spent about a month just working out how to display the C64s Fist backgrounds on A8 and writing code to convert them to my A8 code (ok, not as a full time job, in fact nowhere near but you see my point).

 

I'm a lot more experienced on C64 than A8 but I don't prefer one machine over the other, they both have endless possibilities for producing good games.

 

 

Just my 2p worth (again lol)

 

Pete

[frenchman]

Exactly, works the other way around too. If it's not done on C64 because nobody had bothered with it, you cannot claim it's not possible.

 

To be honest, i was being a tad sarky there; in this case there are other games have done isometric 3D on the C64 to similar specifications, meaning it's proven to a reasonable degree by those if not specifically by a working iso 3D version of [a]Amaurote[/b] - that's a different matter to using the argument in a more general sense as you did when i picked you up on it and the David Crane analogy doesn't work in the latter case because as i said there's nobody taking the "i've done it" role.

 

 

There you go, that backfired didn't it. But that's the trouble with the C64er's, always taking the mick (trying hard anyway)....but don't know much.

 

And another blanket statement seemingly designed to annoy anyone who might call themself a C64er like myself. This is why I got into an argument the other night you have no idea how much I know or TMR knows but we don't try to tell you that you know less than anyone. And Atarianwhatever still thinks I'm the rude one

 

Pete

 

 

Hey, I thought you accepted my apology, obviously not. Ok, no worries. Guess as atarian63 said, I AM THE NICER PERSON. Thanking you.

Edited September 4, 2009 by frenchman