C64 -> Atari 2600 port #01

[ZylonBane]

2600 Choplifter's been discussed before. The main flight area wouldn't be too hard, but the ground area gets absolutely choked with moving objects. Without the little herds of hostages running around (and getting shot/bombed/squashed), it just isn't Choplifter.

[vdub_bobby]

2600 Choplifter's been discussed before. The main flight area wouldn't be too hard, but the ground area gets absolutely choked with moving objects. Without the little herds of hostages running around (and getting shot/bombed/squashed), it just isn't Choplifter.

993252[/snapback]

Porting everything to the 2600 requires compromises. Just because the game, in its original form, would be extremely difficult to reproduce on the 2600 isn't a reason to write off an idea.

 

You would probably have to change the look a little, but the main factor in its favor is that almost everything is already vertically separated. You could probably redesign the screen a little so that the tanks don't overlap with the hostages (do they anyway?); then you have two sprites, two missiles, and the ball to display the grounded helicopter, the hostages, and possibly any projectiles. Assuming you use the PF for the buildings. It would need flicker, and it would be hard, but I think it could be done.

[Feralstorm]

I could potentially see a little bit of flicker-reduction if the hostages' were changed a bit so they moved in unified groups of up to three, and limit their movement area so only so many 'clumps' would be on-screen at any one time. Wouldn't kill flicker by any means, but it should prevent those "putting everything in the same room in Adventure" moments

 

Can't say I'm a fan of 7800 Choplifter. The graphics look decent, but it lacks the flying inertia of the original computer versions.

[supercat]

I could potentially see a little bit of flicker-reduction if the hostages' were changed a bit so they moved in unified groups of up to three...

993682[/snapback]

 

Or groups of three pairs, since each player sprite could probably accommodate two hostages. Further, it may be possible to use one or both missiles to add more hostages if their shapes are suitably designed.

[Cybergoth]

Hi there!

 

Or groups of three pairs, since each player sprite could probably accommodate two hostages.  Further, it may be possible to use one or both missiles to add more hostages if their shapes are suitably designed.

 

Might work, if you really have it like that:

 

1. copter / plane area (P1/P2)

2. house / hostages area (PF = houses / P1 + P2 + M1 + M2 = 12 hostages)

3. tank area (P1/P2)

 

Then you have only the ball left to do all shots crossing area 2.

 

Or, if you allow the copter to land on 2.:

 

1. copter / plane area (P1/P2)

2. house / hostages area (PF = houses / P1 + M1 = copter+shots / P2 + M2 = 6 hostages)

3. tank area (P1/P2)

 

Well, I'd suggest trying kernel 2 first. If that works, the rest is peanuts

 

Greetings,

Manuel

[Heaven/TQA]

would archon not be possible??? but maybe it needs too much RAM for the board... or would be archon II better?

 

http://atari.fandal.cz/detail.php?files_id=1332

 

what about Rally Speedway?

 

i would like to see a real fast scrolling game...

 

http://atari.fandal.cz/detail.php?files_id=2802

 

something like this could be done as well?

 

http://atari.fandal.cz/detail.php?files_id=4190

 

or an nice underrated shoot'em up:

 

http://atari.fandal.cz/detail.php?files_id=3115

 

or 2-player fun:

 

http://atari.fandal.cz/detail.php?files_id=3123

 

http://atari.fandal.cz/detail.php?files_id=3085

[Cybergoth]

Hi there!

 

something like this could be done as well?

 

So you want to compile a list of 10-12 A8 classics for next months poll?

 

Greetings,

Manuel

[legeek]

Can't say I'm a fan of 7800 Choplifter. The graphics look decent, but it lacks the flying inertia of the original computer versions.

993682[/snapback]

 

I agree. I love the 5200 version for the analogue control.

 

I voted Blue Max, but would love a Super Charger version of Space Taxi when we get to that year

 

Cheers,

Ben

[Heaven/TQA]

ehm...how would you do blue max' 3d iso scrolling?

[ZylonBane]

The same way Desert Falcon did it, obviously.

 

Anyway, Choplifter is an odd duck. The actual gameplay is a bit twitchy and maybe even somewhat monotonous. At the time it came out, I believe a huge amount of its appeal was the superb animation. It was that era's version of an eye-candy game. Also, the droves of hostages inspired a certain "gotta catch 'em all" mindset. Surely I'm not the only one who insisted on rescuing a full load of hostages, just so I could watch 'em all unload clown-car-style at the post office.

 

So a port of Choplifter that feels like Choplifter would have to capture all these elements-- the base gameplay mechanics, the slick animation, and the herds of hostages.

[Cybergoth]

Hi there!

 

ehm...how would you do blue max' 3d iso scrolling?

The same way Desert Falcon did it, obviously.

 

Or Spitfire Attack style.

 

Greetings,

Manuel

[vdub_bobby]

Rather than using an entire player for one hostage, especially since that would seem to create some relative-size issues with the tanks/chopper/planes also being one player in size, it would also be feasible to use a single, unduplicated sprite for two hostages:

Or even three or four:

 

EDIT: Here's a possible Choplifter mockup. The helicopter and tank are single double-width sprites, the hostages are duplicated sprites, the house is PF.

 

This mockup has the helicopter and the hostages never overlapping vertically. This probably isn't doable as it is now, but it's close.

Edited January 5, 2006 by vdub_bobby

[ZylonBane]

That looks like -- to use the vernacular -- ass.

 

Without the big high-res smoothly-animated chopper... it's just not Choplifter. It would have to use both players, like BMX Airmaster did.

[djmips]

That looks like -- to use the vernacular -- ass.

 

Without the big high-res smoothly-animated chopper... it's just not Choplifter. It would have to use both players, like BMX Airmaster did.

994680[/snapback]

 

Looks pretty good to me, and it is smoothly animated, how come you can't see that!!! (look closer... closer.... no closer...)

[vdub_bobby]

Using two sprites next to each other would have a lot of flicker.

 

And depending on whose ass it looks like, that could be good or bad.

[ZylonBane]

No more than 30Hz flicker, which is totally acceptable. There's really only one large object that could conflict with the chopper at any given time-- in the sky, the jet or homing mine. On the ground, the barracks. Simple.

[Gateway]

992307[/snapback]

 

[SeaGtGruff]

Re: Choplifter--

 

I think you could do the chopper using 1 player and its missile, by changing the player's and/or missile's size and/or position from one scan line to the next. Here is a mockup of what one frame of the chopper could look like by doing that:

 

 

Obviously, this would mean having one table for the player graphics data, another table for the player size, another table for the player movement value, plus similar tables for the missile. And there would have to be different tables for just about every frame (tilt of the chopper, not to mention the rotation of the blades). But I think it could be doable, at least while the chopper is in the air. When the chopper lands to pick up men, it's facing toward the viewer and isn't as wide, so probably only one player would be needed there.

 

The tanks could be done in a similar fashion, possibly using just one player per tank, double-size pixels, just moving the shape one clock left or right from one scan line to the next to simulate a finer resolution and a wider sprite.

 

Michael Rideout

[ZylonBane]

When the chopper lands to pick up men, it's facing toward the viewer and isn't as wide

No, the chopper can be facing any direction when it lands.

[SeaGtGruff]

When the chopper lands to pick up men, it's facing toward the viewer and isn't as wide

No, the chopper can be facing any direction when it lands.

995150[/snapback]

 

I had never played Choplifter before yesterday, but last night I downloaded an Apple IIe emulator and the original Apple version of Choplifter, because I tend to think of the original versions of games as the "most authentic" versions.

 

Whenever I landed the chopper to pick up men, the chopper faced the viewer, no matter which way it was facing just before it landed. I don't know how any other versions of Choplifter are programmed, and I haven't played the Apple IIe version umpteen zillion times yet to see how it behaves in every conceivable situation, but that's the behavior I saw last night while I was playing it.

 

I thought it was very cool, actually, because if there were men running to the chopper from either side, it made it look like they were climbing into either side of the chopper. I figured the original programmer had made it do that by design.

 

Michael Rideout

[vdub_bobby]

Obviously, this would mean having one table for the player graphics data, another table for the player size, another table for the player movement value, plus similar tables for the missile.

You can combine a lot of that data into one table. HMxx data only uses 4 bits, missile size only uses 2 bits, player size 3 bits.

 

Plus if you could cut some elements out then it would be a lot more doable.

 

Like, if you could leave the player stationary (while moving the missile) but leave missile size unchanged (while changing player NUSIZx), then you could get all that data very easily into 1 byte:

   lda (),Y
  sta HMM0
  and #$0F
  ora MissileSize  ;<--could replace with constant, maybe
  sta NUSIZ0
  lsr
  sta ENAM0

Less data and easier cycle time within the kernel.

That would just require two tables. It would take a ton of scanline time; using SwitchDraw would take...29 cycles. Actually, that's not too bad. With some clever use of VDELxx, you probably could draw two sprites that way in the sky area, where you aren't drawing anything else.

[ZylonBane]

I had never played Choplifter before yesterday, but last night I downloaded an Apple IIe emulator and the original Apple version of Choplifter, because I tend to think of the original versions of games as the "most authentic" versions.

 

Whenever I landed the chopper to pick up men, the chopper faced the viewer, no matter which way it was facing just before it landed.

Interesting. I've only played the Atari 800 version (and a little bit of the arcade version), and in that one the chopper stays however it was when you land. So the Apple version just "snaps" to the forward-facing orientation when you land? Ick.

 

Here's an interesting comparison of the various versions of Choplifter:

http://www.tomheroes.com/Video%20Games%20F.../choplifter.htm

[Cybergoth]

Hi there!

 

Choplifter already existing on the Atari 8-bit AND the 7800.  It's kinda been done to death.

 

I thought this was a pretty interesting argument, so I researched some more console versions:

 

Archon => NES

Choplifter => Coleco, 7800, SMS, SNES

Frantic Freddie => Coleco

Gateway to Apshai => Coleco

 

Greetings,

Manuel

[djmips]

So the Apple version just "snaps" to the forward-facing orientation when you land? Ick.

 

The Apple version is canon, so you are wrong.

[ZylonBane]

"Ick" is a personal opinion, therefore it can't be wrong, therefore you are wrong.