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Atarisoft -- Missing in Action

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I thought there was supposedly a proto of it back in the day but it never got released. There was something weird about it like Sega was going to do the port.

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Vector graphics games are impossible on the TI. :P

 

 

(just a bait for the experts of the impossible)

 

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Vector graphics games are impossible on the TI. :P

 

 

(just a bait for the experts of the impossible)

 

 

But it could be done using a standard 3D wireframe engine, particularly if one leverages the F18A GPU, although I still think it should be feasible on a stock TI with some calculation optimizations and look up tables. I'll add it to my "maybe some day I'll get around to do it" folder :)

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And what's wrong with Blasto! Lol

 

While Blasto is a good game, it is by no means a replacement for Battlezone.

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Okay... Almost every freaking platform of the era seems to have an Atarisoft port of Battlezone...

EXCEPT the TI! What the heck is up with that?

 

battlezone.png

 

http://www.youtube.com/watch?v=ymrYkbEbnEQ

Now-I don't consider myself to be an uber coder of any description but I can't and won't accept that the VIC20 could do a reasonable attempt at Battlezone and the 4a could not, I mean, come on it's a F**kin VIC20! :mad:

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Now-I don't consider myself to be an uber coder of any description but I can't and won't accept that the VIC20 could do a reasonable attempt at Battlezone and the 4a could not, I mean, come on it's a F**kin VIC20! :mad:

 

Sorry to tell you.

 

 

Considering the number of home-grown clones for the Commodore 64, it is perfectly possible for the VIC-20. They both use the same CPU core: the VIC-20 uses a real 6502 while the Commodore 64 uses a 6510 which is a 6502 with an on-board I/O port. The VIC-20's VIC video chip lacked the higher resolution of the 64's VIC-II (amongst a few other things not relevant to the game.)

 

The direct-memory model of the VIC-series video chips help out a LOT for graphics. That said, even though register-based access to video memory is a bottle neck, ColecoVision games and modern 4A coders have proven how much more is possible with the 9918 than we grew to expect way-back-when.

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Vector graphics games are impossible on the TI. :P

 

 

(just a bait for the experts of the impossible)

 

 

Maybe hard to do, but they could do a reinterpretation of the graphics much like what happened with the Star Trek Strategic Operation Simulator. That was a vector graphics game in the arcade and came out fairly well as a TI port.

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Considering the number of home-grown clones for the Commodore 64, it is perfectly possible for the VIC-20. They both use the same CPU core: the VIC-20 uses a real 6502 while the Commodore 64 uses a 6510 which is a 6502 with an on-board I/O port. The VIC-20's VIC video chip lacked the higher resolution of the 64's VIC-II (amongst a few other things not relevant to the game.)

 

the Vic-20 doesn't have realtime 3D graphics like the original version, just sprites in different size... the soul of battlezone is totally killed

Edited by rocky007

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But it could be done using a standard 3D wireframe engine, particularly if one leverages the F18A GPU, although I still think it should be feasible on a stock TI with some calculation optimizations and look up tables. I'll add it to my "maybe some day I'll get around to do it" folder :)

 

My fastest line draw code so far can only manage about 50 lines per second - sacrificing color you might get up to about 75 - let's generously say 80 for math reasons. I'd love to be beaten but I was doing the measurements to see if vector games were feasible. I'd still say "not very". If you want 10 frames per second, and need to draw and erase (cause that's faster than clearing the screen), then you've 80 lines/second divided by an overhead of 20 frames per second (one draw, one erase, 10 times), and that gives you just 4 lines per frame. Even if you accept 5 frames per second, you've still only got 8 lines. (On average. Shorter lines are faster, longer lines are slower.)

 

The F18A GPU should be plenty fast for line drawing, of course, particularly on the overlay screen where there's a single-instruction to plot a pixel.

 

Of course, you can easily simulate vector games with pattern characters, and there's no reason that can't reproduce all the vector games out there with reasonable success. :)

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Yeah, that K-Rappy little Commode-A-Dore even have the vector game Omega Race.

A game that I put entirely too many quarters into in my youth.

 

Arcade Version

http://www.youtube.com/watch?v=BgIYtzccPnw

 

VIC 20 Version

http://www.youtube.com/watch?v=3Sa2aDxvxJ8

 

We'll probably never see a port for this classic game either. :(

This game requires the drawing of only a few orthogonal lines at any one time, and these are extremely fast to draw. As for the rest, Rasmus has already demonstrated it it can be done very succesfully. Perhaps we can interest him in doing a port? ;)

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I understand the need for purity, eg-the vector look but in terms of playability-the Atari 2600 version was actually very good.

 

Maybe an higher spec version for the 4a based on the 2600 conversion would turn out better.

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If you had enough local RAM you might be able to draw to local RAM and then just update modified bytes but that would still require a lot of screen updates.

I think the simulated 3D using sprites and printable characters is most feasible.
Playability is going to be most important.

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A local buffer would help - one of the big problems with drawing lines on the 9918A bitmap mode is the read-modify-write cycle needed to set a pixel. You are kind of forced to set the address twice for each pixel, meaning that even once you know where it goes, that pixel takes 5 VDP writes (2 bytes each for 2 address sets, plus writing the final byte) and 1 VDP read (to get the current byte for modification) (and each write is a read/write cycle due to the CPU nature, so really, 5 writes and 6 reads!) If you could do the drawing in CPU, the worst case is three writes per (up to) 8 pixels (two bytes address, one byte data, using my extreme example that's 3 writes and 3 reads).

 

A monochrome buffer would take 6k of CPU RAM for the full screen. It does take a couple of frames to get that much data to the VDP (you could of course use a window instead of all of it!) Alternately, it would be interesting to see how well the dirty rectangle approach would work!

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...and after Battlezone, maybe Star Wars: The Arcade Game? :P

We have a version of Star Wars, now. I have a ROM that might be a prototype?

 

the Vic-20 doesn't have realtime 3D graphics like the original version, just sprites in different size... the soul of battlezone is totally killed

So far as I know, no home computer from that era has a hardware 3D graphic engine. No home computer from the era had the capabilities of the arcade machines of which ports were made. So we do or do without.

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Other than it being a challenge to program or to see if it could be done, I'm not quite sure porting old arcade games would be at the top of my list for new TI software. I personally would simply use MAME to play the original, but that's just me. Of course, it helps that I have an X-Arcade Tankstick to do so!

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Yeah, that K-Rappy little Commode-A-Dore even have the vector game Omega Race.

A game that I put entirely too many quarters into in my youth.

 

VIC 20 Version

http://www.youtube.com/watch?v=3Sa2aDxvxJ8

 

We'll probably never see a port for this classic game either. :(

 

I had the VIC-20 and the Omega Race cartridge and I very much doubt the graphics was that good/detailed. This is more in line with my memory ...

 

;)

 

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