Atari ST Games Ported to the Jaguar

[Sargon]

Holy cow, I was expecting to see the NES-like adventure game, which is still neat.. but that looks like an arcade port of Willow. I never played the arcade game, but it looked nice.

 

Actually, now I see that video is from the arcade version. Here is the ST version, which sadly looks pretty awful...

 

[Stage_1_Boss]

 

Actually, now I see that video is from the arcade version. Here is the ST version, which sadly looks pretty awful...

Oh, .. uh, yeah, I mean.. it's a game. I'll go back to sticking with my desire for the Elvira: Arcade Game. hehe = )

[+CyranoJ]

Excuse my crappy playing, it's not easy when the view is about 10 frames behind the input. I really should buy a better capture card:)

 

No sound yet.

 

This one is more of a milestone than it appears. It features partial emulation of GemDOS file I/O. Most of the games done to date have either been single loaders (load, remove disk, done) or have had no file system and have accessed data directly from the disks (easy, replace disk call with ramdisk load). This one, however, loads data using GemDOS calls (#$3d, #$3f, #$3e). With this working, many more titles are now possible.

 

https://youtu.be/v8AGTyPsTuM

[+af0l]

Wow. Wouldn't mind having to solve that problem Inspired by your endeavours, I jumped right in and went to see about converting Chaos Engine to the Jag. Days later, I have my first breakpoint set at where I believe is the start of unpacking code, with no idea where it all ends Not easy.

[Welshworrier]

You'll probably want to add in the extra gemdos calls, fseek in particular, fdup at a push and possibly fcreate if you wanted to redirect that to eeprom save

[+CyranoJ]

You'll probably want to add in the extra gemdos calls, fseek in particular, fdup at a push and possibly fcreate if you wanted to redirect that to eeprom save

 

Yup, fseek is already in. I'll add the others when I need them.

 

In the meantime, the Amiga music was... um.... IS THAT MUSIC? So I used the Arcade tracks instead:

 

https://youtu.be/4jkD2NwPrQI

[Welshworrier]

It is a steampunk xevious isn't it

 

Fdup is a relatively easy one to simulate, only issue is what to do when the original file link gets closed and the DUP is still open (so a check in the fclose). But I guess I'm telling you advanced egg sucking

[+Saturn]

That's amazing. Love the 1942-esque/Raiden type games. Will definitely be in for a trio of this one.

[skip]

Wow. Wouldn't mind having to solve that problem Inspired by your endeavours, I jumped right in and went to see about converting Chaos Engine to the Jag. Days later, I have my first breakpoint set at where I believe is the start of unpacking code, with no idea where it all ends Not easy.

That sounds awesome. I hope it goes well. Hopefully well enough to eventually chuck the Amiga music and speech back in there

 

Was Chaos Engine STE enhanced?

 

I wonder, and I have no idea of the technicalities of this, if STE enhancements (scrolling? colour?) could be put into conversions? I'd love to see Obsession Pinball (STE only) or Starball Pinball (which had some STE specifics IIRC) on the Jaguar.

[+CyranoJ]

That sounds awesome. I hope it goes well. Hopefully well enough to eventually chuck the Amiga music and speech back in there

 

Was Chaos Engine STE enhanced?

 

I wonder, and I have no idea of the technicalities of this, if STE enhancements (scrolling? colour?) could be put into conversions? I'd love to see Obsession Pinball (STE only) or Starball Pinball (which had some STE specifics IIRC) on the Jaguar.

Might be worth talking to Mr Bitmap if you are serious about chaos engine.

 

He was very accommodating with xenon 2.

[+af0l]

Might be worth talking to Mr Bitmap if you are serious about chaos engine.

 

He was very accommodating with xenon 2.

 

 

Right - I was meaning to do that, if I ever get that far. I think it's way above my skill level ATM anyway, wouldn't want to waste the mans time. But it really seems a game that just fits the Jaguar, that's what got me going...

 

Meanwhile, I got to the point where I think the binary is unpacked (we're talking about the intro here). Now to figure out how to make that even load (and crash) on the Jag

[+CyranoJ]

Well, here we are:

• Music from the arcade (All 5 levels have their own music, original ST version only had 4 music tracks for 5 levels)
• SFX from the YM (the amiga SFX samples sounded like someone held a phone up to a metal sponge and pressed record)
• Screen map redraw routine converted to GPU (still occasionally drops frames, might port the sprite routine as well if I get bored)

Such a great game, my dad loved to play it - one of his favorites. He'll be up there smiling

 

https://youtu.be/fJZx3KDekyo

Edited September 26, 2016 by CyranoJ

[+af0l]

Good job!

 

He'll be up there smiling

 

 

... while the rest of us cry, thanks to some dipweeds whose fathers didn't teach them the subtle difference between right and wrong...

Edited September 26, 2016 by af0l

[+remowilliams]

Well, here we are:

• Screen map redraw routine converted to GPU (still occasionally drops frames, might port the sprite routine as well if I get bored)

Nicely done, plays rather well Moving the sprite routine to GPU would probably be nice as well.

[+af0l]

Moving the sprite routine to GPU would probably be nice as well.

 

... as would be (dare I say it?) a binary release?

[Stage_1_Boss]

 

... as would be (dare I say it?) a binary release?

I'd buy that for a dollar! .. (or $55 for a clear cart version)

[ls650]

Looks fun.

[+af0l]

Might be worth talking to Mr Bitmap if you are serious about chaos engine.

 

He was very accommodating with xenon 2.

 

 

Well, it seems that Rob Northen was used here (I suspect external variation) as every file seems to be encrypted. This will take time or Mr. Bitmap's cooperation.

[+CyranoJ]

 

 

Well, it seems that Rob Northen was used here (I suspect external variation) as every file seems to be encrypted. This will take time or Mr. Bitmap's cooperation.

 

Just crack it

[+af0l]

 

Just crack it

 

Now, that wouldn't be fair... on me

[+CyranoJ]

Well, this one is being tested at the moment. I'm very happy with the end result

 

• Partial GemDOS file I/O emulation
• Music taken from the arcade version, and an extra track added (for level 5) which isn't in the ST release
• SFX taken from the ST
• Re-code of the map scrolling routine on the GPU
• Re-code of the sprite routines on the GPU
• The above 2 have allowed the 20Hz frame limiter on the ST version (3 vbls) to be changed to 30 Hz (2 vbs) for the Jaguar - making the game much smoother with no slowdowns
• High scores saved to EEPROM
• Cheat mode (but I'm not saying how to activate it!)
• Removed the 'Sounds by J C Brooke' on the attract screen
• Near instant loading between levels (there is around 30-40 seconds on the ST for disk access)

I may be using the cheat in the below video.....

 

https://youtu.be/-Bog9_urKxI

[+af0l]

Pimped it up good!

[Papa]

'96 Jaguar is discontinued...

 

"Eh..they'll pick it back up in a couple decades."

 

[Zerosquare]

• The above 2 have allowed the 20Hz frame limiter on the ST version (3 vbls) to be changed to 30 Hz (2 vbs) for the Jaguar - making the game much smoother with no slowdowns

It looks choppy on the YouTube video ; is that your capture card?

[+CyranoJ]

It looks choppy on the YouTube video ; is that your capture card?

 

Yep, it's a c®apture card.