Incredible use of A1200 AGA chipset and CPU. Beat em up ARCADE.

[roondar]

System friendly or not, not using Sprites/Blitter/Copper at all is a waste even if you do render from Fast RAM. Blitter perhaps less so (though it should be doable to give it something to do while the code is running game logic in Fast RAM), but Copper/Sprites are basically 'free' if you render from Fast RAM.

Edit: I'm not entirely sure the performance seen here is representative of use on a real A1200 + Fast RAM. Would be nice of course, but in my experience 68020+ emulation is almost always faster than the real thing. Which tends to not be a problem with older software, but is a pretty big caveat when coding on an emulator first and only later checking on real HW.

[grond]

Well, the "levels" are rather short, if you ask me. Do they perhaps fit entirely into the 2MB chip? Then all you have to do would be to hardware scroll ("no custom chips" clearly isn't supposed to rule out scrolling) and to CPU-blit bobs.

[Daytona675x]

Very nice work! And not incredible but very credible

@roondar

in my experience 68020+ emulation is almost always faster than the real thing

I can second this. Depending on what you do an emulated naked A1200 (cycle exact, full chipset emu) is muuuuch faster in WinUAE than the real thing. For my soccer game I ended up setting WinUAE's CPU Frequency to "Custom (6.9 MHz)" instead of "4x (A1200)" with its 14 MHz to make it appear ~ as slow as my real A1200s during gameplay Even with the "2x (A500)" setting the emulator is still significantly faster in my use case...

not using Sprites/Blitter/Copper at all is a waste even if you do render from Fast RAM.

He's certainly using FMODE 3 and hardware scrolling, so sprites become almost useless, at least with DMA and therefore their wide modes are broken too. He could probably use the copper to manually adjust 16 pixel wide sprites to draw some score info or so, that would also grant him access to some otherwise unused colors for that task. The blitter is useless for what he's doing.

[pink^abyss]

Originally Posted by jotd

that too good to be true. And not using the blitter... what?

Sorry, I'm saying it's fake until proven otherwise.

As the original game is only ~3MB sized and now needs 64mb maybe all gfx are simply preshifted and then longword copied with the cpu? atari style

[roondar]

Originally Posted by Daytona675x

He's certainly using FMODE 3 and hardware scrolling, so sprites become almost useless, at least with DMA and therefore their wide modes are broken too. He could probably use the copper to manually adjust 16 pixel wide sprites to draw some score info or so, that would also grant him access to some otherwise unused colors for that task. The blitter is useless for what he's doing.

I'll grant that finding use for the Blitter will be hard given this method, but it's not entirely impossible for it to still be useful in some minor way. Basically, my idea is to try and find use for it while the game code is otherwise engaged. Not trivial, but not necessarily impossible/useless.

Regarding Sprites, I was indeed thinking of using 16 pixel wide ones set up via the Copper. Gives you a 128 pixel wide 4 colour overlay (more if you want to get adventurous - you could make a full screen overlay with some effort), which in the given situation is basically 'free' as the Copper/CPU will normally not be in contention for DMA slots on AGA when the Blitter is not in play (or only to a very small degree). Given the colour palette he also has enough colours left to do this without impacting the rest of the visuals.

Other potential Copper use is more obvious, such as reloading colours/creating gradients, etc. Given the now 'free' nature of the Copper, you could go completely overboard with it and still not lose cycles for the CPU GFX copy actions (except for CPU/Blitter updates to the Copperlist of course).

[mcgeezer]

Fast ram alone cannot be enabling this result, the CPU speed must be being increased as well. I'm hoping I'm proved wrong though so I'm going to start doing some tests myself (AGA 68020 with extra fast ram).

[Tigerskunk]

Originally Posted by mcgeezer

Fast ram alone cannot be enabling this result, the CPU speed must be being increased as well. I'm hoping I'm proved wrong though so I'm going to start doing some tests myself (AGA 68020 with extra fast ram).

Same here, I don't see that speed coming from an 020.

[Ami]

Is 68020 can only access max 16MB?

[roondar]

Originally Posted by Ami

Is 68020 can only access max 16MB?

The one in the A1200 (68EC020) is indeed limited to 16MB, but a full 68020 would be limited only to 4GB.

[grond]

Are there any full 020s in any Amigas?

[Lord Aga]

Not without adding a card I guess.
None in the basic configs.

[roondar]

I thought the A2500 was sold with a full 68020 CPU card. Whether or not that is a 'true' Amiga model is a different kettle of fish, but it's there.

[saimon69]

Want to be honest: for me if a game takes like 64MB of RAM to work has to be MINIMUM at the size of a FallOut or a Blasphemous, not just a darn Final Fight!

[jotd]

if I can run that on my A1200/060 I'll believe it. And I'm not shocked if it needs 64MB of ram. No problem.

[Retro1234]

how exactly would you do 128 colour parallax?

[Bruce Abbott]

Originally Posted by dlfrsilver

if you want the maximum you need to go low level on these systems.

System friendly is limiting.....

You can go 'low level' and still be system friendly, and there are plenty of good reasons to do so.

Originally Posted by mcgeezer

Fast ram alone cannot be enabling this result, the CPU speed must be being increased as well. I'm hoping I'm proved wrong though so I'm going to start doing some tests myself (AGA 68020 with extra fast ram).

I'm hoping you are wrong too, but afraid you are right. That the game needs 64MB proves it was not tested on a stock A1200 with FastRAM, but a more accelerated machine or (worse) an emulator.

Still it will be interesting to see what can be done with the stock EC020 and 4-8MB of FastRAM. This is the standard that should have developed for the A1200.

[jotd]

Definitely not buying it.

Share the exe so everyone can see how good it is.

Windows executables don't count.

[masteries]

Any idea regarding compiler environment?


I am searching for a cross compiler environment plus bobs/sprites/sound libraries for Amiga 1200, it order to program for it using a PC Windows machine

Originally Posted by aros-sg

High memory usage may suggest he uses pre-shifted bobs. This would simplify and speed up things like optimized rendering (like never restoring areas which were covered by bobs in previous frame and again in current frame).

Exactly as I do in Metal Slug port for Atari STE, currently it takes 3.2 MB RAM instead 3.6 MB summer ´21 release

[jotd]

Bartman VS code certainly looks neat

but you need to build everything from the ground.

I saw your work and that certainly looks impressive.

I can suggest you try to rebuild my relatively simple arcade games (Pacman, Amidar https://github.com/jotd666/amidar500/tree/master) using vasm 68k (windows version) + notepad++. Maybe that doesn't qualify as an environment but that's pretty simple.

My source code contains some blitting routines and also ptplayer source code from phx (for music & sfx). Creates a simple executable which contains everything.

[masteries]

Originally Posted by jotd

Bartman VS code certainly looks neat

but you need to build everything from the ground.

I saw your work and that certainly looks impressive.

I can suggest you try to rebuild my relatively simple arcade games (Pacman, Amidar https://github.com/jotd666/amidar500/tree/master) using vasm 68k (windows version) + notepad++. Maybe that doesn't qualify as an environment but that's pretty simple.

My source code contains some blitting routines and also ptplayer source code from phx (for music & sfx). Creates a simple executable which contains everything.

Thanks for your support and suggestions!


Yes, as IDE I use Notepad++ for STE and MegaDrive, xD





I am targeting the A1200, due to I want to use non preshifted bobs and stream load the scenario background from Fast RAM.



MegaDrive version fits in 1 MB (no preshifting is needed, sprites can be mirrored by hardware with no performance penalties, audio is still the same digitalized one as STE), and probably the A1200 has enough power to mimic MegaDrive performance and capabilities.


But as language I need C language, not assembly; although the inner functions can be programmed in assembly.


We can start asking to more programmers in this forum,