Asteroids Emulator, When Did This Happen?

[Tin_Lunchbox]

I was checking Atarimania.com this morning for one thing or other and chanced upon the arcade Asteroids emulator in what seems at first glance to be finished form. OMG!

 

http://www.atarimania.com/game-atari-400-800-xl-xe-asteroids-emulator_s20091.html

 

I tried it in Altirra, no joy but it's probably just some setting. I don't have time to fiddle with that right now. But I tried it in A800 and whoopee! Runs right off the bat! It has sounds!

 

Merry Christmas early, and thanks Santa!

[TMR]

I was checking Atarimania.com this morning for one thing or other and chanced upon the arcade Asteroids emulator in what seems at first glance to be finished form. OMG!

 

It happened during the yearly ABBUC competition. Lovely, isn't it? =-)

 

[Ransom]

Wow! Finally, a great Asteroids for the A8. I can't wait to give it a go.

[Bunsen]

Tin, join in at ABBUC and you will be informed

 

Norbert did a great job! The Atari has enough power to emulate the vector display, the sound circuits and the processing unit (a 6502!) of the original arcade.

[adamb2k5]

Great remake!

[Ransom]

Tin, join in at ABBUC and you will be informed

 

Norbert did a great job! The Atari has enough power to emulate the vector display, the sound circuits and the processing unit (a 6502!) of the original arcade.

 

It's so cool that the programmer was able to emulate the actual Asteroids hardware on the A8 and got the original Asteroids code running on it in real time.

[Hatta]

Seriously? He's emulating a 6502 on a 6502 in real time? I'm guessing he was able to use static recompilation to avoid the overhead of doing it on the fly?

[Rybags]

The 6502 isn't emulated, the main task is emulating the vector hardware. The actual game code would run natively with of course some strategic patching that removes stuff not needed, redirects certain jumps/calls, alters hardware writes etc.

 

1st gen arcade Asteroids used discrete sound generation so I'd guess xxl probably did the sounds from scratch. The trick there is to find parts of the code that trigger each sound event and change e.g. to RMT calls. With some games you get lucky and they already have a sound subroutine in place where everything goes to. With others there might be hits to hardware all over the place which makes a bigger job of it.

 

The vector hardware uses a sort of display list (vector list?) where object processing drives the beam around - effective resolution for start/end draw events IIRC is 1024 x 768, this translates (sort of) neatly down to 256 x 240 rez.

[Pengwin]

I never realised this existed till this post.

What an amazing achievement! Why couldn't Atari themselves put this out years ago?

[Ransom]

I never realised this existed till this post.

What an amazing achievement! Why couldn't Atari themselves put this out years ago?

 

I know! Imagine what a hit it would have been for the A8!

[Rybags]

The concept of this sort of emulation layer wasn't so prominent back then.

Besides, the arcade/home divisions never really got along, they'd probably had offered little help.

[Synthpopalooza]

I was wondering at the possibility of other Atari vector games being done in this manner ... particularly, stuff like Tempest or Space Duel. I did a mockup once which uses a software mode that simulates 320x192 at 4 colors + BG, using 8K screen ram ...

 

It's in this post: http://www.atariage.com/forums/topic/204060-asteroids-emulator-other-games-possible/page__hl__%2Btempest

[Rybags]

The later games tended to have more objects. Space Duel would be great if it could be pulled off.

 

I think Battlezone would be a logical next vector game, another instance of the ported version not being well received.

[+Allan]

I would think Luner Lander would the the easier one since it came out right after Asteroids.

 

Allan

[ledzep]

http://web.utanet.at/nkehrer/

 

He seems to be pretty prolific in terms of coding.

[+Stephen]

Damn - that's an impressive software resume.

[Synthpopalooza]

For anyone who wants to try porting Tempest to the 8-bit, this resource might help: http://ionpool.net/arcade/tempest_code_project/tempest_code_project.html

[Tin_Lunchbox]

Merry Christmas early, and thanks Santa!

 

I must add "Thank you Mr. Kehrer and all concerned."

[sack-c0s]

I'm working my way around a Commodore 16 framework - I've got it up and running on the C64, but it seems to suffer from not having the colour choice that the C16 has, but I'm guessing that even though the colour placement isn't as good on the Atari people didn't monkey around with the colourRAM so much due to having to cram everything into 12k of RAM and it'll all balance out nicely.

 

Once that's done I can have a 'new old' games running on the Atari. Failing that I've got a few 6502-based MAME ROMs in my sights. One pretty much loaded into the C64 and ran but the screen didn't quite fit, but I can push the screen out a bit on the Atari and it'll work I think

[Rybags]

I've done 2 C16/Plus4 conversions although 1 is a VBXE exclusive.

 

As you've said the C64 deficiency is lesser colour choices, there's also the slower CPU speed to contend with.

 

On Atari the 128 character limitation and different bitmapping scheme are big gamestoppers. VBXE makes it easy though since it's fast enough to actually recreate a bitmapped image from a character screen if you wanted.

For Quadrillion I just let the game do the graphics natively and got VBXE to blit the data over to a linear Atari screen.

 

Sound is pretty easy - since the base clocks are the same on both machines it's a simple case of a little bitshifting and some table-lookup to convert the frequency values over.

 

I looked into doing 6502 arcade conversions, one of the big stopping points was that I couldn't find documentation on the hardware used - although I was probably barking up the wrong tree, probably best to use Mame drivers and code as a reference point rather than chasing datasheets or trying to reverse-engineer based on program behaviour.

[sack-c0s]

I can't remember how I did it - I think I used the driver to find the load addresses for the ROMs and then just probed around the debugger

[Retro Rogue]

The concept of this sort of emulation layer wasn't so prominent back then.

Besides, the arcade/home divisions never really got along, they'd probably had offered little help.

 

Not to mention living in the real world, not the hobbyest world. There's certain things like project development time constraints (which is based around dev time planning, manufacturing, distribution, etc.), budgets, more projects in the que, etc.

 

And it wasn't that they didn't get along that there was never any help from coin - they were just never asked. Marketing usually picked what "hot" games they wanted in the que for production in Consumer, it was added to the project list and when a programmer was free they'd pick a game (unless a manager specifically assigned a game). Coin was never consulted, and often had no idea one of their games was being done in Consumer until after it was released. The "animosity" you're talking about was in regards to the original developers of the game not getting credit, and more importantly not getting any of the bonus money the Consumer guys got for doing their game.

 

Franz Lanzinger is a perfect example. He had no clue that Crystal Castles was being converted until after the fact and would have liked to have been involved or at least tapped for guidance.

 

I would think Luner Lander would the the easier one since it came out right after Asteroids.

 

Allan

 

No, Lunar Lander was before Asteroids. Lunar Lander was released in August '79 and Asteroids was in November '79.

[tschak909]

The later games tended to have more objects. Space Duel would be great if it could be pulled off.

 

I think Battlezone would be a logical next vector game, another instance of the ported version not being well received.

 

Battlezone made heavy use of the mathbox bit slice coprocessors for 3D transformation. This alone eliminates Battlezone from being potentially ported.

[Mr.Amiga500]

I was checking Atarimania.com this morning for one thing or other and chanced upon the arcade Asteroids emulator in what seems at first glance to be finished form. OMG!

 

I never heard about this either. Thanks for posting.

 

The first video games I ever saw were in 1980 when I saw three arcade machines: Asteroids, Centipede and Berzerk. I've always been pleased with Atari 8-bit Berzerk and Centipede (5200 version), but Asteroids on the Atari never quite did it for me - until now. It's great to have all three on my 800XL.

[Cebus Capucinis]

This isn't exactly the right place for the question, and I could likely look it up somewhat easily, but since Marty led me in the direction of wondering, I figured he'd have the answer relatively more easily than I can find:

 

Were the claims about royalties somewhat justified in terms of business numbers? I mean, did Coin generate the same amount of revenue as Consumer at any point, or at least a significant enough portion of it to warrant payouts of royalties? Did Warner sort of take the stance of using this disparity in revenue (if it existed) as a means of explaining lack of royalties? For example, right before the crash, we know that Consumer was generating a pretty sizeable amount of income. Was Coin matching that at all or even reaching near that amount? I'd think that since the big boom of video games was both in an arcade sense and a home sense, there would be similar numbers.

 

However, since Coin's "end client" was primarily distributors, rather than consumers, there's an extra step in that business model so the bulk of the revenue from end-users, of course, would go to distributors. But were orders significant enough from arcades and distributors to reach nearly the amount of money Consumer made at its peak?