[WIP] Tetris conversion

[jotd]

there is no such option but yes I could add it.

[franeti]

Thanks for this amazing port JOTD, the amiga community are lucky with your work!

I love these Amiga ports more than new games, because at the time we could only dream that one day they would be released for our machine like Tetris or games that were released but were not up to the standard of our Amiga.
I encourage you to keep making more of these!

[jotd]

If I live 800 more years I guarantee to port all MAME games

[VincentGR]

LOL
Thanks for the games jotd.
A question (not a request).
Would it be hard to port a game like SEGA's Repulse to the Amiga?
It was also a bootleg of it called Son of Phoenix.

[Seiya]

wow, i'd like to be a programma to port everything on Amiga.
@jotd
but, a part programming knowledge, what kind of software need to port another platform game to Amiga without the source code.

[jotd]

Would it be hard to port a game like SEGA's Repulse to the Amiga?

I didn't know the game, just watched a video. I think it's perfectly doable on A500 with all colors (with copper tricks, as the images are static). Zooming can't be done in real time (I suspect they already had hardware zooming since them Buck Rogers 1982 game and just before Outrun) apart from that it could be done.

what kind of software need to port another platform game to Amiga without the source code.

First, MAME with its debugger (transpose it to any platform MAME doesn't support if it exists). You absolutely need this to RE the game properly. Even if you have the source it will be handy to check values at run time. It can also record videos, and if you hack the game to turn off music or find the proper service mode, you can isolate game sfx.

Then, you need to convert the assets (specially graphics). I use python+custom libs. Sometimes using PNG as exchange/debug format.

I transcode 95% of the game code using my self-written tools (I have written z80 and 6502 to 68000 converters). Then it's manual rework to fill the missing parts & debug the wrong ones. And for the amiga side, it's standard game development (open screen, blitter, sprites...)

[Retroplay]

Repulse, sweet memories of this one although it was Proma's or possibly Kyugo's "'99 - The Last War" version I played back in the day.

[mrv2k]

If you leave the attract mode running you get some characters left on the instructions when it clears for the next set of text. Not sure if this happened in the original.

[jotd]

If you leave the attract mode running you get some characters left on the instructions when it clears for the next set of text. Not sure if this happened in the original.

probably not. I'll fix this. And will add pause as someone requested, along with music off option.

[franeti]

Originally Posted by jotd

If I live 800 more years I guarantee to port all MAME games

Hahaha, Just in case, start with shinobi or double dragon!

As you know both are in amiga very bad ports… make your magic jotd
Just for understanding , would they be difficult to port?

Shinobi had a not official port to megadrive and double dragon one user here started the port a long time ago but he didn’t finished…

[jotd]

Shinobi is of course difficult, as a 8 way platformer with a lot of colors & enemies at the same time. Means a lot of blitter, no efficient way to use sprites... If I'd do those I'd probably got AGA directly. 8-way scrolling looks tough (check devlog of standby Black Tiger ...). A lot of blitting is involved, plus you have to manage to preserve the backgrounds, use double buffering to avoid flicker... all adds up to create a more complex game, and the risk of not working at 50 fps or even 25.

Double Dragon is 8 way but more like side scrolling. Also slightly older means less power required.

Plus I don't pretend to do wonders with amiga hardware. Just managing.

In case you're wondering why most of those 16-bit arcade ports aren't finished, it's super hard to make those in asm or C but easy to throw a few sprites in Scorpion show a vid of first level without enemies, then make all people hope. But I would say that 1 project out of 10 is completed (Acid Bottle shows it's possible, also the creators of Green Beret, and Rastan is probably going to be done too), because most people stop as soon as there's some planning required.

Also I found out that if you use the transcode method you get a rougher start but once it works you don't get stupid bugs and the game is perfect. I found out the hard way with Karate Champ that I first almost completed without the source code (only resourced A.I.) then threw it all away and re-did in transcode for a full success with a lot of debugging but overall less work.

Projects I'd like to see are non-Scorpion ones like Robocop AGA or Black Tiger.

Sorry for the book I just wrote

[franeti]

Originally Posted by jotd

Shinobi is of course difficult, as a 8 way platformer with a lot of colors & enemies at the same time. Means a lot of blitter, no efficient way to use sprites... If I'd do those I'd probably got AGA directly.

Double Dragon is 8 way but more like side scrolling. Also slightly older means less power required.

Plus I don't pretend to do wonders with amiga hardware. Just managing.

In case you're wondering why most of those 16-bit arcade ports aren't finished, it's super hard to make those in asm or C but easy to throw a few sprites in Scorpion show a vid of first level without enemies, then make all people hope. But I would say that 1 project out of 10 is completed, because most people stop as soon as there's some planning required.

If the game is already in megadrive for example that has same motorola, is it easy to port ussing a engine like scorpion?
Just for curiosity, This is a video of shinobi megadrive port

[ Show youtube player ]

[jotd]

MD port looks brilliant. Scorpion would be an easy way to see if the game is viable on amiga.

Let's not forget that the megadrive is litterally made for those: lots of tiles & sprites. But if the coder shared his 68000 code & assets, it would save a lot of work for the person willing to take up the challenge.

[Cris1997XX]

Originally Posted by jotd

MD port looks brilliant. Scorpion would be an easy way to see if the game is viable on amiga.

Let's not forget that the megadrive is litterally made for those: lots of tiles & sprites. But if the coder shared his 68000 code & assets, it would save a lot of work for the person willing to take up the challenge.

That project isn't finished as far as I know, and it will probably never be. There haven't been any news in years

[jotd]

small update as I fixed an annoying display bug and added pause

[hexaae]

Binary link?

[jotd]

first post

[hexaae]

Can't see Releases builds on GitHub...

[jotd]

itch.io as always

[VincentGR]

https://jotd666.itch.io/tetris1200