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Re: Prince of Persia

Posted: Sun Apr 14, 2024 12:38 pm
by thegg
Really impressive work. Must have taken a lot of hours. I admire your dedication and attention to detail. Well done.

Re: Prince of Persia

Posted: Sun Apr 14, 2024 1:16 pm
by Lechuck
thegg wrote: Sun Apr 14, 2024 12:38 pm Really impressive work. Must have taken a lot of hours. I admire your dedication and attention to detail. Well done.
Thanks, Thegg!

Yes, it took me one year to complete it (well, not 100% of the time, but I worked on the game an important part of my free time :D )

But I really enjoyed it. It was really rewarding.

Thanks again

Re: Prince of Persia

Posted: Mon Apr 15, 2024 2:03 pm
by orion70
I'm absolutely impressed! No words to describe what can be squeezed out of a VIC-20. I didn't even imagine that this could be accomplished, even in my wildest dreams - yep I know we had arcade quality shooters, Popeye and Frogger and Pac-Man and so on very close to the originals, and everything from huge RPGs to Doom, but heck, PoP is more an Amiga game than a 8-bit one!

Re: Prince of Persia

Posted: Mon Apr 15, 2024 3:19 pm
by Lechuck
orion70 wrote: Mon Apr 15, 2024 2:03 pm I'm absolutely impressed! No words to describe what can be squeezed out of a VIC-20. I didn't even imagine that this could be accomplished, even in my wildest dreams - yep I know we had arcade quality shooters, Popeye and Frogger and Pac-Man and so on very close to the originals, and everything from huge RPGs to Doom, but heck, PoP is more an Amiga game than a 8-bit one!
Thanks a lot, Orion70!,

Yes, I always saw POP as a game from the 16 bits era, so, was very surprised when found out that it was, in fact, first created for an Apple II, that shares the 6502 with our beloved VIC… :D . The more I read about the game, the more Impressed I was about what Jordan Mechner was able to do from scratch. So, when I saw the version for the Spectrum, I thought it would be funny to try to something similar. And yes, it’s been certainly funny.

Cheers

Re: Prince of Persia

Posted: Mon Apr 15, 2024 3:46 pm
by beamrider
That looks really impressive. I briefly played this on the Amiga and never imagined we'd have a Vic conversion. Congratulations on your achievement.

Re: Prince of Persia

Posted: Mon Apr 15, 2024 5:25 pm
by Ola H
I, too, have just briefly played PoP on the Amiga and it didn't really click with me. But as I hold Jordan Mechner's other games in very high regard, I have always thought I should return to it one day. This might be the perfect opportunity as everything is more fun on the Vic :D

Thank you and congratulations on a very unexpected conversion!

Re: Prince of Persia

Posted: Tue Apr 16, 2024 11:34 am
by Merytsetesh
This is really incredibly good. I've never played Prince of Persia but I've heard so many stories about it: it, and its development, are something out of legend. And here it is on the humble VIC-20... I'm speechless, and profoundly impressed.

I don't know the game, but I am curious if it would be possible or useful to load blocks of the game from disc to ease memory problems.

Anyway... good grief. Well done! *bows*

Re: Prince of Persia

Posted: Tue Apr 16, 2024 12:05 pm
by Lechuck
beamrider wrote: Mon Apr 15, 2024 3:46 pm That looks really impressive. I briefly played this on the Amiga and never imagined we'd have a Vic conversion. Congratulations on your achievement.
Thanks Beamrider!,

I never played it in a real Amiga, but tried it recently in an emulator. And found it is almost identical (if not exactly the same) to the DOS version I remembered. That was, certainly, a great conversion :)

Cheers

Re: Prince of Persia

Posted: Tue Apr 16, 2024 12:06 pm
by Lechuck
Ola H wrote: Mon Apr 15, 2024 5:25 pm I, too, have just briefly played PoP on the Amiga and it didn't really click with me. But as I hold Jordan Mechner's other games in very high regard, I have always thought I should return to it one day. This might be the perfect opportunity as everything is more fun on the Vic :D

Thank you and congratulations on a very unexpected conversion!
Thanks,

if you ever decide to try it, I hope you enjoy it. This version is, certainly, much easier and simpler than the Amiga one...

Cheers

Re: Prince of Persia

Posted: Tue Apr 16, 2024 12:16 pm
by Lechuck
Merytsetesh wrote: Tue Apr 16, 2024 11:34 am This is really incredibly good. I've never played Prince of Persia but I've heard so many stories about it: it, and its development, are something out of legend. And here it is on the humble VIC-20... I'm speechless, and profoundly impressed.

I don't know the game, but I am curious if it would be possible or useful to load blocks of the game from disc to ease memory problems.

Anyway... good grief. Well done! *bows*
Thanks!

regarding the question about the disk, yes, I'm already loading parts of the game from disk (couldn't get everything to fit in memory at once). So, screen definitions for every level has to be read from disk. Appart from that, level 3 reads chars for the skeleton (replacing the 'normal' guard chars). Level 4 reloads the 'guard' chars and loads a different set of chars for the 'Palace' levels (4,5 and 6). In level 7, 'normal' chars for the dungeons are loaded again. After level 9, some additional code is loaded to, someway, replicate the 'Shadow Man' sword fighting (when working on that, I had already used all the available memory so, for that part, I'm replacing part of the code that is no longer used. And, finnally, there are two additional disk files for the two endings (happy one with the Princess hug, and sad one when you run out of time). So, I'm afraid that some pacience is required when runing it in a real VIC...

Cheers

Re: Prince of Persia

Posted: Tue Apr 16, 2024 12:24 pm
by Lechuck
Just uploaded a new version to fix another bug reported in the VIC-20 FB group. As pointed out there, problem is that I wasn't initializing a zero page address I'm using. After a normal reset it is 0 (what is OK with the game) but it takes a different value if any BASIC statement is used, provoking two 'Princes' instead of 1 being drawn. That is now fixed.

Cheers

Re: Prince of Persia

Posted: Wed Apr 17, 2024 2:47 am
by Mayhem
This is quite something. I loved the C64 port, but this is even more staggering. Does it use the original Apple II 6502 code like the C64 port did?

Re: Prince of Persia

Posted: Wed Apr 17, 2024 11:13 am
by Lechuck
Mayhem wrote: Wed Apr 17, 2024 2:47 am This is quite something. I loved the C64 port, but this is even more staggering. Does it use the original Apple II 6502 code like the C64 port did?
Thanks Mayhem,

no, I didn't use the original code. I downloaded it to have a look, but I'm terrible at interpreting what other have done, even with code as well structured as the one provided by Jordan Mechner. What I found really interesting was the pdf with notes provided by him. It gives a very good overview about how the different parts of the game are structured.

Cheers

Re: Prince of Persia

Posted: Thu Apr 18, 2024 2:09 pm
by bjonte
This looks fantastic! The wall perspective suits the hardware and hides the wide pixels nicely. Good choice to use hires.

Re: Prince of Persia

Posted: Fri Apr 19, 2024 11:30 am
by Lechuck
bjonte wrote: Thu Apr 18, 2024 2:09 pm This looks fantastic! The wall perspective suits the hardware and hides the wide pixels nicely. Good choice to use hires.
Thanks!

yes, it would have been great to have the 'Prince' drawn in multicolor mode (using three colors as the C64 version), but the losse in resolution, didn't worth it (IMHO). Using Hires allows a very recognizable aspect, even in just Black & White.

Cheers