MiSTer FPGA Forum

Hi,

I'd like to ask you long time Amiga fans and Gurus (meditating or otherwise) a question about CPU speed.

Whenever I hear about speed improvements in the FPGA or upgrading to a faster processor with real hardware, there's always a demonstration of Elite 2, Indy Racing and other 3D Games (besides DOOM and all the fancy newer ports of PC games).

My question is, are there any real benefits for the 2D games as well? Will Lotus run faster? Will Moonstone have a better frame-rate?

Is there effectively any advantage to a gamer looking to play only classic Amiga games?

No, not unless additional work has been done on the game (outside of those 3D games you mentioned, which do benefit).

2D Amiga games generally run at the same frame rate no matter what the CPU speed is.

2D games on the Amiga relied heavily on the custom sprite hardware of the machine and this hardware is CPU independent.
Its different on the Atari ST, here sprites were handled in software and the game could be more dependend of the CPU. In reality most games didn't run better with a faster CPU, but there were some games that benefitted (unintentionally) from a faster CPU like Darius+. Interesting enough, I just tried Lotus 3 on the ST, because I thought this one would defnitely run faster, but it seems the engine was frame capped.

Another World runs much more smoothly on better CPU's. Probably because it is also using filled vectors.

More speed is always a nice thing to have

https://www.youtube.com/watch?v=PE5_pd2WABA

limi wrote: ↑Sat Aug 15, 2020 7:51 am No, not unless additional work has been done on the game (outside of those 3D games you mentioned, which do benefit).

2D Amiga games generally run at the same frame rate no matter what the CPU speed is.

That depends. If the game's logic is tied to the CPU speed itself, then having a better/fasyer CPU can break the game's code. Alcatraz is a good example of that

People want a better CPU for various productivity reasons but also for demos. A better CPU is also great if you want to run a classic mac environnement and have access to the Mac library of games at the time.

Some other games also benefit a lot from it due to the back calculations they do, Cicilization, Colonization, Sim City 2000 and games of that kind are prime examples of that

Fularu wrote: ↑Thu Sep 17, 2020 10:13 am Some other games also benefit a lot from it due to the back calculations they do, Cicilization, Colonization, Sim City 2000 and games of that kind are prime examples of that

That's what I was looking for... thanks

Fularu wrote: ↑Thu Sep 17, 2020 10:13 am Some other games also benefit a lot from it due to the back calculations they do, Cicilization, Colonization, Sim City 2000 and games of that kind are prime examples of that

While this is technically true, none of these games do so much calculation that speed improvements beyond what MiSTer’s accelerated 68020 CPU already does today will really be noticeable. Productivity apps, 3D demos and 3D games are still the main beneficiaries of a faster CPU.

Is there any Amiga that runs Sim City 2000 at a playable speed? It’s probably the slowest running game released. No point at all running it on Amiga, but it’s amusing to see how anyone could sell such poor software with, presumably, a straight face.

Optiroc wrote: ↑Thu Sep 17, 2020 7:22 pm Is there any Amiga that runs Sim City 2000 at a playable speed? It’s probably the slowest running game released. No point at all running it on Amiga, but it’s amusing to see how anyone could sell such poor software with, presumably, a straight face.

The Mac version actually runs better under ShapeShifter emulator than the Amiga version. I guess the Amiga version is just poorly optimized...

limi wrote: ↑Thu Sep 17, 2020 2:13 pm

Fularu wrote: ↑Thu Sep 17, 2020 10:13 am Some other games also benefit a lot from it due to the back calculations they do, Cicilization, Colonization, Sim City 2000 and games of that kind are prime examples of that

While this is technically true, none of these games do so much calculation that speed improvements beyond what MiSTer’s accelerated 68020 CPU already does today will really be noticeable. Productivity apps, 3D demos and 3D games are still the main beneficiaries of a faster CPU.

Afaik Sim City 2000 runs much much better with a 68040. This was a port of the Mac version which was made with Quadras in mind

I can't get Another World to run it all. It just freezes at a green screen after the initial code screen

EDIT: I figured out what's wrong. I fixed it. My install of Amiga was crap, so I reinstalled properly and now every game works.

RalphJB wrote: ↑Wed Sep 30, 2020 6:51 pm I can't get Another World to run it all. It just freezes at a green screen after the initial code screen

That's nice, green is such a lovely colour. I fail to see how CPU speed would benefit you here though. Is it just that it would it get you to that green screen you crave that nanosecond faster?

Try a different version, or try changing CPU/chipset & memory options. I'd expect 68000 CPU with OCS/ECS & 1mb chip should work fine.

As a former original Amiga hardware owner back in the late 80s/early 90s...

Most of the amiga games that benefit from CPU speed improvements are IMHO better played on the PC core if they will run. They tend to be later games and likely have 256 colour VGA support, sound blaster, etc.

The amiga only really benefits from faster CPU for productivity apps or 3d polygon games. Anything sprite based is likely fixed to the speed of the custom chips which are in turn fixed to the video processing of PAL or NTSC video. You’ll only get better performance on those if they were too slow to keep up and generally those games were tuned pretty well for the hardware they were released for.

Polygon games are different, the Amiga had no 3d hardware and it was all done in software on the CPU, and the CPU wasn’t very strong for it.

Back in the day almost all Amiga games were either written for the 68k at 7 mhz or the 68020 at 14 mhz, machines beyond that were simply way too expensive and rare for games to target them. Not like the PC where people upgraded CPU speed on a regular basis; for games on amiga there were only really two processor speeds during the life of the machine that mattered - A1000/500/2000 68k at 7mhz and A1200’s ‘020 at 14 (for AGA games). Some of the AGA games may benefit from faster CPU, but as above... they’re generally also on PC as well with more detail/features/etc.

throAU wrote: ↑Fri Oct 02, 2020 7:50 amMost of the amiga games that benefit from CPU speed improvements are IMHO better played on the PC core if they will run. They tend to be later games and likely have 256 colour VGA support, sound blaster, etc.

The amiga only really benefits from faster CPU for productivity apps or 3d polygon games. Anything sprite based is likely fixed to the speed of the custom chips which are in turn fixed to the video processing of PAL or NTSC video. You’ll only get better performance on those if they were too slow to keep up and generally those games were tuned pretty well for the hardware they were released for.

Yeah, I just got an 060 expansion for my Amiga 1200. You have to look into ports from other systems and emulators like DOSBox, ScummVM and ShapeShifter to be able to take advantage of such a CPU with Amiga games.

Even Sim City 2000 is a port I think? Here by port I mean a game that got ported unofficially and probably after 1994 where the Commodore went bankrupt and the Amiga almost completely stopped getting any new games released for it.

It is still fun to tinker with though, making an Amiga setup that would be the kind of Amiga you wish you would have had if Commodore had not become bankrupt.

Caldor wrote: ↑Mon Nov 02, 2020 11:34 am
It is still fun to tinker with though, making an Amiga setup that would be the kind of Amiga you wish you would have had if Commodore had not become bankrupt.

Oh for sure.

I've got my A4000 equivalent running on Mister

But for those who never had original hardware and just want to play some games / experience what the system was like back in the day with a minimum of hassle, ECS, kickstart 1.3 and 68000 @ 7mhz are probably what you want. As above most 2d games are custom chip speed bound and tweaked to run within those constraints. I have seen some 2d games run too fast (Zool, for example I think runs faster than normal if you crank the processor speed up), but I wouldn't really consider that a significant benefit.

The animation on 2d games won't really get smoother without just running faster like a 3d game will, as the 2d artwork had to be drawn in individual frames whereas a 3d polygon game can draw multiple frames if cpu speed is available for each second of game time...

AGA games - there are a few gems, but by the time AGA was released the PC had hit its stride for gaming and unless you're specifically playing the game on Amiga to remember your childhood - if the same game is on PC from the mid 90s or later, it's generally going to be a better experience in AO486 if you can get it to run - you'll have 256 colours at higher resolution and generally much better frame rate, and the sound is "good enough" or better

Wing Commander is probably one of the few non-polygon games (its still 3d but 2d sprite scaling - which again the amiga can't do in hardware) on the Amiga I can remember that definitely benefits from CPU speed. But then, again - it's just way better played on PC.

There are some cases where the Amiga still has its benefits... but that is probably still mainly games released much later. Like the updated version of Eye of the Beholder 1 and 2 where you get a built in auto-map feature and the full ending sequence of EoB1, that the PC version did not have. While also having the 256 color graphics of the DOS version.

Worms Directors Cut is also an Amiga exclusive gem.

When it comes to just being able to play the games, the Minimig core already does what it needs to do. It can run all the most relevant games and run them well, because its always special cases when it comes to needing hardware beyond the Amiga 1200 with a few extra MB RAM. Generally playing games the best way they can be played... well, its just so individual. Some might find it easier to go with emulators that support a full range of games without risking a lower than optimal framerate, which is a problem for AO486 f.ex. with many games.

But I love all the options we have... and its just so much more interesting to do emulation on an FPGA than it is on a Pi or using other types of emulation. My goal with my Amiga is to try to make it as compatible as possible, and I think even with an 060 I can make it quite compatible.

But using an FPGA, it so much less hassle since you can have so many configurations that changes the hardware and roms, and one thing I want to focus on is making CD32 games work. I got it to work on my real Amiga 1200 and I am pretty sure I can get it to run quite well on the MiSTer Minimig core. An advantage that the CD32 has over the DOS versions of the same games, I think, is how these games are designed to take advantage of a gamepad instead of needing a mouse. You usually can get a joystick or gamepad to work for DOS games, but less setup would be needed for the CD32.

Of course... many of those games were then also released on f.ex. MegaCD (or at least I expect they were). But the Amiga probably had better audio in many cases. When it comes to CD32 though, many of the games would certainly benefit from a higher CPU speed. Gloom being one example, and that is another example of a game that was only released on the Amiga. I think it needs something like an 030 or equal to run at full speed.