Outrun AGA

[agermose]

Originally Posted by trixster

Any screenshots to tease us with? Or it's too early for that?

I can do better than some screenshots. Video coming today.

[agermose]

Originally Posted by Steril707

Not to sound too negative, but wouldn't it be more helpful to announce something when you have a working demo or something?

I did want to show something, and that is why I wrote "more coming soon". Video coming later today.

[agermose]

Here you go, first public video of Outrun AGA in action.
It is mostly a tech demo to prove the road engine works. So please disregard the glitches.
Disclaimer: I added the Ferrari directly from the arcade. The number of colours on it will have to be reduced later.
Make sure to turn on the audio.

Some more technical details to come later.

[ Show youtube player ]

[jotd]

it looks good! Maybe a bit slow?

[agermose]

Originally Posted by jotd

it looks good! Maybe a bit slow?

It is slow, because I just set the speed to some constant number. There is no control of the car yet.

Also the game slows down to 25 fps at some points. I haven't implemented throttling of the speed to framerate yet.

[wiz12]

It already looks better than the original.

[Gryfon]

Great work, really looking forward to seeing how you progress!

[DanyPPC]

Is this only for A1200 base ?
Perhaps it could be better to use an A1200 + Fast Ram, a very standard nowadays.

[agermose]

Originally Posted by khph_re

At least he has a 'track' record for getting things done though.


One thing I wonder, with A1200 memory expansions now being common and cheap, could development be for A1200 +fast ram? If commodore had lived, I expect 1995 would be when they moved to that format.

"Track record" got me laughing

[agermose]

Originally Posted by DanyPPC

Is this only for A1200 base ?
Perhaps it could be better to use an A1200 + Fast Ram, a very standard nowadays.

A1200 base yes. I want it to run on basic AGA setups.

[Tigerskunk]

So now we are talking.. *thumbsup*

[Lisko]

Oh what a good news! I hope you'll have a smooth and trouble-free coding roadmap and if you'll ever need a tester you can count on me. Keep up!

[agermose]

Some technical details for the interested.

The arcade has many gfx layers:
Road 0, road 1. Priority can be changed.
2 tile layers, used for horizon gfx.
Sprites (128).
Character layer.
Screen size 320x224, framerate 30 fps.

Main CPU (68K at 12.5 MHz) runs the main game code. The secondary CPU (68K at 12.5 Mhz) takes care of creating data for the road HW. Then there is a sound CPU (z80).
Custom HW for road generation, sprite scaling, HW scrolling etc.


The main 2 challenges are the road generation and the sprite engine.


Technical details for the Amiga version, subject to change.
AGA base HW, PAL only.

AGA dual playfield, 4 bitplanes each.
Screen size 288x224. FMODE4 bitplane fetch.
Playfield 1 is used for road 0, (and horizon gfx later).
Amiga HW sprites are used for road 1. FMODE4 used for 64 pixel sprites.
Playfield 2 is used for the sprite, and text layers. Only the Ferrari sprite is there at the moment.

The main and secondary CPU code has been disassembled from ROM, and modified for use in the Amiga version. The single Amiga CPU (68020 at 14.2 MHz on A1200) runs the code from both CPU's, sequentially. The MAME debugger is really helpful, to get the code right. I have also looked at Cannonball (by Chris White) code, for the code I'm unsure of what it does.

The road display code, simulating the custom road HW of the arcade, is optimized heavily for AGA hw, and uses very few resources. Big thanks to legendary MAME developer Aaron Giles, for reverse engineering the Outrun arcade HW.

Sound is done using a MOD player at the moment.

The sprite engine is the next big task.
Getting all the sprites into 15 simultaneous colours (PF2) will be a major challenge. As will scaling the sprites, without excessive memory usage, and keeping a high framerate.

[str0m]

Slightly off topic, was the arcade really only 25fps? I thought it was 30? The Japanese Saturn version has a 60fps mode which is how I play it. You lose a slight sensation of speed but it's a lot smoother. Also has "arranged" new versions of the music tracks.

Dreamcast version is arguably the most arcade accurate as it is 25/30fps and no gear indicator just like the arcade. The Saturn ports show L/H gear but that's a good thing with no physical gear lever to look at!

[DamienD]

Originally Posted by agermose

Big thanks to legendary MAME developer Aaron Giles, for reverse engineering the Outrun arcade HW..

Yup Aaron Giles is a legend

Same as another MAME Dev; David Haywood i.e. Haze.

[agermose]

Originally Posted by str0m

Slightly off topic, was the arcade really only 25fps? I thought it was 30? The Japanese Saturn version has a 60fps mode which is how I play it. You lose a slight sensation of speed but it's a lot smoother. Also has "arranged" new versions of the music tracks.

Dreamcast version is arguably the most arcade accurate as it is 25/30fps and no gear indicator just like the arcade. The Saturn ports show L/H gear but that's a good thing with no physical gear lever to look at!

Yes you're correct, the arcade ran at 30 fps. Video clock at 60 Hz.
On PAL Amiga the 30 fps corresponds to 25 fps.
I've corrected the original post.

[dlfrsilver]

How many colors do you plan to make the game with ?

[saimon69]

AND, if ever Fedepede04 finish its work on the tweaking of old outrun in the STE so to port we might also have a decent version in ECS one day...

[saimon69]

Originally Posted by dlfrsilver

How many colors do you plan to make the game with ?

Am not involved with the project but i think that the dual playfield AGA sgould provide a decent coverage of assets from megadrive, with some palette tweaks per area, the car sprite with its own 16 colors plus a good deal of copperlists...

... if the project reach PC Engine port quality will be already good

[jotd]

for the scaling, maybe have less frames if you can't pre-compute them (low memory), and have cached copies of scaled sprites on high-end amigas. A lot of people have 4MB/8MB even more on their classics.