Atari v Commodore

[AtariNerd]

Hmmm, ponder this...

 

Some people on a forum dedicated to a specific machine think that manner that machine goes about doing things is the bees knees and express they believe, that it is better than said x other machines.

 

Subjective, but not unreasonable given it is a forum for said machine. It is expected they might have an affinity for it above others - after all THAT'S WHY THAT FORUM EXISTS.

 

Some other people from another forum hear of this and take offense to the notion that that could ever be, but instead of keeping their disagreement on a forum dedicated to their own machine of choice, decide to launch a coordinated offensive on said first board by taking the time to register,etc to 'educate' the masses there.

 

Regardless of arguments, just on the surface, doesn't one of those two groups seem a bit battier than the other?

 

Is it just me?

 

Please, just leave us in peace... this is our home. If you think us daft, laugh at us from afar.

 

Don't make yourself a joke here.

Edited June 2, 2009 by AtariNerd

[atariksi]

@atariksi:

 

You are putting so much effort to mention GTIA modes with its 80x192 resolution... And how much of colors you get in them...

But can you name a game that really uses that modes to produce a good colorfull game ?

 

Koronis Rift.

 

It shows approx. 48 colours per screen and the CPU has the time to calculate an extra layer that fades the mountains into the scene, using the 256 colour palette.

 

It seems people just go by what they saw by their limited experience-- most games did not use GTIA modes so they think Atari is stuck with 160*200*5. At least they should acknowledge the hardware supports higher color depth and that GTIA is a real graphics mode. Graphics 10 gives you the GPRIOR "OR" mode to enhance resolution so you could get away with some 2X zoomed sprites positioned at odd color clock values since the "OR" mode works at color clock resolution. Graphics 9/11 resolution enhancement would uses player 5 "OR"s only and requires repositioning sprites on a line basis.

[popmilo]

...you have to give some credit ...

I said it before and I'll say it again: "Atari has better colors and faster cpu and faster io"

 

I'm not trying to compare graphic modes in general, Im just looking for a proper mode that I could use in my application.

I wasn't trying to deny gtia mode existence, just saying it isn't good choice for arcade platform game with lots of enemies and shooting and jumping ...

 

It works great for "Koronis Rift" ! Its way ahead of its time...!

 

I don't want "squashed" aliens for enemies in my game, I want proper aspect ratio for them.

 

Like I said, 5 players give me 40 pixels in a line to improve colors... That is only quarter of screen

Player only, takes at least 12 pixels, so I have 28 pixels for the enemies and background improvement...

What do I do with it ? Use it for two enemies ? -24 pixels ... Im down to 4 pixels to improve colors in that part of screen....

 

And I want to put at least 5-6 enemies on same horizontal level as the player...

Im sorry the game is organized like that, its supossed to be platform game... gravity works downwards... platforms are horizontal... enemies walk on horizontal platforms and there are just so many of them trying to kill the player

 

>> There are other tricks like Boulderdash and other games use, and these are all 50/60Hz.

What tricks they use ?

 

p.s. I know I should probably ask these questions in a programming topic, but guys posting here really seem to know their stuff so Ill use it...

and its just such a great fun to read this topic

p.p.s. Questions about GTIA modes here: http://www.atariage.com/forums/index.php?showtopic=145045

Edited June 2, 2009 by popmilo

[jvas]

...you have to give some credit ...

I said it before and I'll say it again: "Atari has better colors and faster cpu and faster io"

 

I'm not trying to compare graphic modes in general, Im just looking for a proper mode that I could use in my application.

I wasn't trying to deny gtia mode existence, just saying it isn't good choice for arcade platform game with lots of enemies and shooting and jumping ...

 

It works great for "Koronis Rift" ! Its way ahead of its time...!

 

I don't want "squashed" aliens for enemies in my game, I want proper aspect ratio for them.

 

Like I said, 5 players give me 40 pixels in a line to improve colors... That is only quarter of screen

Player only, takes at least 12 pixels, so I have 28 pixels for the enemies and background improvement...

What do I do with it ? Use it for two enemies ? -24 pixels ... Im down to 4 pixels to improve colors in that part of screen....

 

And I want to put at least 5-6 enemies on same horizontal level as the player...

Im sorry the game is organized like that, its supossed to be platform game... gravity works downwards... platforms are horizontal... enemies walk on horizontal platforms and there are just so many of them trying to kill the player

 

>> There are other tricks like Boulderdash and other games use, and these are all 50/60Hz.

What tricks they use ?

 

p.s. I know I should probably ask these questions in a programming topic, but guys posting here really seem to know their stuff so Ill use it...

and its just such a great fun to read this topic

p.p.s. Questions about GTIA modes here: http://www.atariage.com/forums/index.php?showtopic=145045

 

 

If you want to see a well designed platformer with many colors, check my favourite:

 

http://www.bigfivesoftware.com/atari/BBSB/...ens/screens.htm

 

(it looks even better in action, not just screenshots)

[popmilo]

If you want to see a well designed platformer with many colors, check my favourite:

 

http://www.bigfivesoftware.com/atari/BBSB/...ens/screens.htm

 

(it looks even better in action, not just screenshots)

 

Played it, good game...

 

Alas... But...

only two enemies on the same horizontal line.... and both of them 8 pixels wide and one color....

[Crazyace]

Bullcrap. You can't do Graphics 1, 2, 3,4,.. etc. You have emulate them which hogs up CPU time; to me (and anyone with some neurons), that means Atari mode is superior. Atari does those graphics modes in hardware w/o involving CPU especially if you add scrolling, overscan, and zooming effects.

 

Really, I'm surprised you would state something like all Atari advantages are related to just it's color range given you participated in this thread. It's like going through a semester of Calculus and at the final exam not knowing the derivative of x*x.

 

The point is that the C64 can emulate these modes - even though it may take CPU cycles - the A8 cannot emulate the C64 colour cell graphics at all. That's why it's graphics are superior.

...

 

You can stop the bullcrap. The C64 cannot emulate the Atari's GPRIOR color effects nor the GTIA modes w/wrong colors. Atari can emulate the color RAM vertically quite easily. And it's better to have linear graphics than cell-based graphics so why would we want to do cell-based to begin with. Emulating using up CPU cycles means Atari gets the edge for that particular graphics mode. QED.

 

You want more? C64 cannot equal Atari's re-use of color registers. Not all imagery has color requirements spread out into 8*8 cells over 40*25 grid. Usually colors will cluster toward certain regions unless you hand-made the image in which case the GPRIOR can be used as well.

 

>( When I was speaking about advantages I was only considering graphics - that's why I didn't mention cpu/io/etc , just the colour range )

 

You specifically stated: "Actually all of the Atari strength's come from the enhanced colour ranges -" If you meant only graphics modes, you used invisible ink.

 

>For myself the GTIA modes are tied in to the colour range - they are the big advantage of the A8 over the C64, and nothing on the c64 matches the 256 colour mode for pictures/photos

 

Hey, but then you can't draw a conclusion that C64 graphics modes are superior. GTIA modes are both more colorful and have a corresponding graphics mode assigned to them.

 

Interesting - You state that the C64 can't show gr1,2,3,4 , I state that it can. Then, rather than accepting that, you state that the C64 cannot emulate the GPRIOR effects - I never said it could.

 

I can, and have drawn a conclusion that the C64 graphics modes are superior to the A8. You disagree - which I'm actually fine with, as you seem to consider the GTIA modes way more important than anything else. I think that the cell based colour was actually better - especially the way that 'per cell' the resolution could be switched from 160 to 320.

 

( Oh and instead of invisible ink I was using context - but next time I'll be clearer )

[jvas]

If you want to see a well designed platformer with many colors, check my favourite:

 

http://www.bigfivesoftware.com/atari/BBSB/...ens/screens.htm

 

(it looks even better in action, not just screenshots)

 

Played it, good game...

 

Alas... But...

only two enemies on the same horizontal line.... and both of them 8 pixels wide and one color....

 

Can be enhanced many ways

- No horizontal sprite multiplexing was used

- Software sprites can be involved

- The sprites have already more than on color: one color per raster line

- The screen design can be changed (as done in Bounty Bob) to "conceal" the "limitations"

[atariksi]

Bullcrap. You can't do Graphics 1, 2, 3,4,.. etc. You have emulate them which hogs up CPU time; to me (and anyone with some neurons), that means Atari mode is superior. Atari does those graphics modes in hardware w/o involving CPU especially if you add scrolling, overscan, and zooming effects.

 

Really, I'm surprised you would state something like all Atari advantages are related to just it's color range given you participated in this thread. It's like going through a semester of Calculus and at the final exam not knowing the derivative of x*x.

 

The point is that the C64 can emulate these modes - even though it may take CPU cycles - the A8 cannot emulate the C64 colour cell graphics at all. That's why it's graphics are superior.

...

 

You can stop the bullcrap. The C64 cannot emulate the Atari's GPRIOR color effects nor the GTIA modes w/wrong colors. Atari can emulate the color RAM vertically quite easily. And it's better to have linear graphics than cell-based graphics so why would we want to do cell-based to begin with. Emulating using up CPU cycles means Atari gets the edge for that particular graphics mode. QED.

 

You want more? C64 cannot equal Atari's re-use of color registers. Not all imagery has color requirements spread out into 8*8 cells over 40*25 grid. Usually colors will cluster toward certain regions unless you hand-made the image in which case the GPRIOR can be used as well.

 

>( When I was speaking about advantages I was only considering graphics - that's why I didn't mention cpu/io/etc , just the colour range )

 

You specifically stated: "Actually all of the Atari strength's come from the enhanced colour ranges -" If you meant only graphics modes, you used invisible ink.

 

>For myself the GTIA modes are tied in to the colour range - they are the big advantage of the A8 over the C64, and nothing on the c64 matches the 256 colour mode for pictures/photos

 

Hey, but then you can't draw a conclusion that C64 graphics modes are superior. GTIA modes are both more colorful and have a corresponding graphics mode assigned to them.

 

Interesting - You state that the C64 can't show gr1,2,3,4 , I state that it can. Then, rather than accepting that, you state that the C64 cannot emulate the GPRIOR effects - I never said it could.

...

You are misreading it. I stated that it's better to have Gr. 1,2,3,4...etc. in hardware rather than have CPU be involved so Atari gets the edge for those graphics modes. If you think it doesn't matter if CPU is involved, then I can use a kernel and fill up all graphics modes with more colors than C64.

 

>I can, and have drawn a conclusion that the C64 graphics modes are superior to the A8. You disagree - which I'm actually fine with, as you seem to consider the GTIA modes way more important than anything else. I think that the cell based colour was actually better - especially the way that 'per cell' the resolution could be switched from 160 to 320.

 

You specifically stated: "Apart from the colour range anything displayable on A8 can be reproduced on C64. " And you drew your conclusion from there. I gave you reasons why I disagree with this so unless you refute those reasons, your conclusion does not follow. You just admitted above GPRIOR effects cannot be done by C64; color re-use can be done more on Atari. Overscan/underscan/hscroll/vscroll/display lists/etc. are all graphics modes related and NOT related to color range. So your premise is false.

 

>( Oh and instead of invisible ink I was using context - but next time I'll be clearer )

 

It's stretching it.

[Jetboot Jack]

popmilo said "And I want to put at least 5-6 enemies on same horizontal level as the player... I'm sorry the game is organized like that, its supposed to be platform game... gravity works downwards... platforms are horizontal... enemies walk on horizontal platforms and there are just so many of them trying to kill the player"

 

Then either you need to dig into software sprites...

 

Or accept sprite flicker

 

Or create the illusion of 5/6 per line with vertical offsets

 

Or you can bite the bullet and re-design the game to accept and work with the hardware sprite limitations of the A8

 

Or decide to do it on another platform that allows your design vision to be more easily implemented.

 

The best games on these early systems are those that work with and exploit the hardware...

 

In a similar vein it would be no good demanding a game puts 9 sprites per line on the C64, since it can only manage 8, well the same applies here, there are ways around the problem, but they may compromise your game design too far to be acceptable to you...

 

sTeVE

[carmel_andrews]

can't seem to find a thread on the subject, but i definately remember hearing/reading that ATARI initially didn't support the 3 GTIA modes (can't remember where i read or heard it)

 

Perhaps Atari wanted to understate the capabilities of their hardware (by not supporting these additional modes initially)

[spookt]

can't seem to find a thread on the subject, but i definately remember hearing/reading that ATARI initially didn't support the 3 GTIA modes (can't remember where i read or heard it)

 

Perhaps Atari wanted to understate the capabilities of their hardware (by not supporting these additional modes initially)

 

Or perhaps the early machines just had CTIA chips instead of the later GTIA ?

Edited June 2, 2009 by spookt

[carmel_andrews]

can't seem to find a thread on the subject, but i definately remember hearing/reading that ATARI initially didn't support the 3 GTIA modes (can't remember where i read or heard it)

 

Perhaps Atari wanted to understate the capabilities of their hardware (by not supporting these additional modes initially)

 

Or perhaps the early machines just had CTIA chips instead of the later GTIA ?

 

 

 

 

 

well according to atari 8 faq, the GTIA was ready before the CTIA but apparently there was a problem or a few bugs in the chip which is why the CTIA came first

[Bryan]

can't seem to find a thread on the subject, but i definately remember hearing/reading that ATARI initially didn't support the 3 GTIA modes (can't remember where i read or heard it)

 

Perhaps Atari wanted to understate the capabilities of their hardware (by not supporting these additional modes initially)

 

Or perhaps the early machines just had CTIA chips instead of the later GTIA ?

well according to atari 8 faq, the GTIA was ready before the CTIA but apparently there was a problem or a few bugs in the chip which is why the CTIA came first

a few bugs in the chip == not ready.

 

The original plan was to ship GTIA, but a version without the GTIA modes enabled (CTIA) was released first to meet schedule. Even when GTIA shipped it still had a couple timing quirks.

[popmilo]

Then either you need to dig into software sprites...

I will

 

Or accept sprite flicker

No I won't

 

Or create the illusion of 5/6 per line with vertical offsets

Or you can bite the bullet and re-design the game to accept and work with the hardware sprite limitations of the A8

I'll just reduce number of colors... That seems like only reasonable option... Reducing colors can be automated... I wouldn't dream hand drawing new sprite and background graphics and changing level design...

 

Or decide to do it on another platform that allows your design vision to be more easily implemented.

I have only two computers with 6502 kind of CPU... C64 and Atari 800XL... And I want to make it work on Atari...

Even if its in strange resolution and less or more colors...

 

The best games on these early systems are those that work with and exploit the hardware...

In a similar vein it would be no good demanding a game puts 9 sprites per line on the C64, since it can only manage 8, well the same applies here, there are ways around the problem, but they may compromise your game design too far to be acceptable to you...

 

sTeVE

Like you said "There are ways around a problem"...

I haven't given up...

[emkay]

Well. Sometimes I ask myself why ATARI coders didn't take usage of the clearest features around?

 

The PM Graphics is not really intended to be always the moving graphics. With fully multiplexing, you can create colourful platforms on the whole screen.

Then the coder could take usage of the charmode and its charmode movement and/or software sprites.

The coder could use different techniques, to animate the moving object then.

-Charset rotation

-Charset cluster usage (as in Dropzone)

 

whatever.

 

 

The idea:

 

The moving objects use simple charmode/cluster movement.

The PM graphics build all platforms and boundaries, where the "softwareprite" moves, jumps on, etc...

In the ranges, the "softwaresprites do not reach", the "free" chars can be used to enhance the background and build extra colours with the overlayed gprior players and missiles.

 

Starting with this, Turrican is only a question of "when will it be done" and not "if it can be done" !

[atariksi]

...

Or create the illusion of 5/6 per line with vertical offsets

Or you can bite the bullet and re-design the game to accept and work with the hardware sprite limitations of the A8

I'll just reduce number of colors... That seems like only reasonable option... Reducing colors can be automated... I wouldn't dream hand drawing new sprite and background graphics and changing level design...

...

When you state "reduce number of colors", are you stating that instead of using the sprites to color the background image you would be using the sprites as moving objects? If background image has more colors on left side or right side where not all sprites go over, you can use the a sprite or two for more colors and re-use them for the rest of the screen as moving sprites. Or as Joust does it and as Jetboot points out, you can have many moving sprites and they mostly appear to be in same horizontal zone but they are offset by a few pixels vertically and even when they do cross, there is some flicker (low probability though).

 

I think Joust combines a player + missile to form a bird and gets 8 birds simultaneously horizontally w/the dragon as another sprite.

[supercat]

CGA font had graphics characters as part of the font; so you could use 1/4 full UL char, 1/4 full UR char, 1/4 full LL char, and 1/4 full LR char to get any 2 colors in a 2*2 and say it's 160*200*16.

 

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Link didn't show up for "Below the Root". With the sprites, C64 would outdo CGA in graphics even without the 640 mode; CGA had no sprites.

 

I don't remember whether BTR used sprites. The ability to render tiles in 16 colors, rather than just cyan, magenta, and white improved things immensely, however.

[frogstar_robot]

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Speaking of CGA, the following is wrong but oh so right:

 

http://www.oldskool.org/pc/8088_Corruption

[emkay]

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Speaking of CGA, the following is wrong but oh so right:

 

http://www.oldskool.org/pc/8088_Corruption

 

Textmode Action and "C64" colours and an additional gfx & sound cards.

 

I still prefer this one:

 

 

 

OK. No 60Hz but the vertical resolution is about 8 times of the PC's video

 

And, btw, with a better HD controller, you easily could reach floating animations an higher sample rates.

[popmilo]

When you state "reduce number of colors", are you stating that instead of using the sprites to color the background image you would be using the sprites as moving objects? If background image has more colors on left side or right side where not all sprites go over, you can use the a sprite or two for more colors and re-use them for the rest of the screen as moving sprites. Or as Joust does it and as Jetboot points out, you can have many moving sprites and they mostly appear to be in same horizontal zone but they are offset by a few pixels vertically and even when they do cross, there is some flicker (low probability though).

 

I think Joust combines a player + missile to form a bird and gets 8 birds simultaneously horizontally w/the dragon as another sprite.

If I try to convert sprites from C64 (and 8 enemy sprites can have 8 different colors...) to atari I have to reduce it to 4 or 5 colors...

 

I would like to avoid "special cases" ...

I want to have one software sprites routine that will display as much of sprites as it can anywhere on the screen ...

Would be nice if its possible to make sprites same size as c64s...

If not I would have to redraw all sprites...

I would use PM graphics for Player and weapons....

 

Emkay's idea sounds like good one... Players and missiles for background, platforms... hmmm.... horizontaly it would fill enough of screen (in wider modes...) and verticaly they would cover whole screen... Characters for enemies... copy chars patterns over screen... it could mean a swarm of sprites flying around with little cost

 

p.s. And it could be done on C64 also! and with more colors

[atariksi]

CGA font had graphics characters as part of the font; so you could use 1/4 full UL char, 1/4 full UR char, 1/4 full LL char, and 1/4 full LR char to get any 2 colors in a 2*2 and say it's 160*200*16.

 

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Link didn't show up for "Below the Root". With the sprites, C64 would outdo CGA in graphics even without the 640 mode; CGA had no sprites.

 

I don't remember whether BTR used sprites. The ability to render tiles in 16 colors, rather than just cyan, magenta, and white improved things immensely, however.

 

Here's CGA font:

 

http://www.seasip.info/VintagePC/5140.html#chargen

 

It has a bunch of characters that could be used for filling in other possibilities rather than just left and right. Text mode offered all 16 colors not just 4 from palette of 16 like in 320*200. I bet a good algorithm would be to use a Vector Quantization and use the best character part that fits the image area being rendered-- that would effectively improve the resolution upto 640*200*16.

[atariksi]

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Speaking of CGA, the following is wrong but oh so right:

 

http://www.oldskool.org/pc/8088_Corruption

 

That one looks like it's optimized for speed rather than resolution. I think they synched up the video writes so that they don't overlap to avoid the "snow" effect; otherwise, you were pretty much limited to writing during vertical retrace.

[emkay]

p.s. And it could be done on C64 also! and with more colors

 

Sure. In hires the A8 can display 8 colours then , and the C64 can display 16 colours.

 

But, how will the C64 reach more than 16 colours in the colour resolution, where the Atari can reach more than 20 colours per scanline? Not to talk about the additional changes every scanline.

[popmilo]

p.s. And it could be done on C64 also! and with more colors

 

Sure. In hires the A8 can display 8 colours then , and the C64 can display 16 colours.

 

But, how will the C64 reach more than 16 colours in the colour resolution, where the Atari can reach more than 20 colours per scanline? Not to talk about the additional changes every scanline.

Here Im talking about sprite layer only:

 

All of Ataris players and missiles combined in quadruple size cover maximum of 40 pixels wide area...

That is 20 characters wide, half a screen...

And missiles have same color as apropriate player... and thats only 4 different colors in one line max... And not any pixel in any color... lines of 8 pixels long...

 

Please correct me if I'm wrong...

 

8 Commodore double expanded sprites in multicolor, cover 8x12=96 pixels wide area...

That is 48 characters.... enough even for pure hardware scrolling with tilemap blocks the size of one sprite...

And every pixel can have any of 3 colors plus each sprite can have one of 16 colors...

That is 10 different colors in one line...

Or if you take unexpanded sprites that gives you 96 pixels= 24 chars wide... in twice nicer resolution than ataris... and again more colors...

 

Lemmings used this method to show background. 7 sprites wide layer in 3+ backround colors. And software sprites in charmode.

[atariksi]

The screen is limited to 8,000 characters (16K at two bytes/character); the character set offers characters that have the left or right half filled in, but that only gets one to 160x100. Further, drawing to the screen is very slow.

 

Speaking of CGA, the following is wrong but oh so right:

 

http://www.oldskool.org/pc/8088_Corruption

 

Textmode Action and "C64" colours and an additional gfx & sound cards.

 

I still prefer this one:

 

 

 

OK. No 60Hz but the vertical resolution is about 8 times of the PC's video

 

And, btw, with a better HD controller, you easily could reach floating animations an higher sample rates.

 

Looks like they didn't interlace the graphics with Graphics 10-- that would have helped especially for videos to boost resolution without using up more memory. And overscan would have helped as well.