Neo Geo games to Jaguar? Would be possible?

[Wilheim]

Hi!

 

Some time ago I got an Neo geo AES. I loved the games made for it! Then I thought: would be possible to port some Neo geo title to the Jaguar?

 

According to the specs, it should be possible. Maybe the sprite engine would be harder to implement. But, who knows?

 

Maybe this discussion was made before, I don’t know. But I put it on the table anyways.

[LordKraken]

This topics had been discussed countless times, but in fact it should stop right at the beginning. Neo-Geo games are HUGE in term of data (up to 330 megabits, i.e. up to 40MB) and afaik the biggest Rom on jaguar can be 6MB. So even before considering the different technical capacities you know you're going to have a problem to store all the assets.

[Ericde45]

and to add to this, the cartridge on NeoGeo can be read at full bus speed. there is a lot of buses in this console. so this huge capacity is also very fast, faster than jag cartridge and jag CD

 

some good reading, about neogeo, and about a lot of console, worth to be all read : https://www.copetti.org/writings/consoles/neogeo/

[agradeneu]

3 hours ago, LordKraken said:

This topics had been discussed countless times, but in fact it should stop right at the beginning. Neo-Geo games are HUGE in term of data (up to 330 megabits, i.e. up to 40MB) and afaik the biggest Rom on jaguar can be 6MB. So even before considering the different technical capacities you know you're going to have a problem to store all the assets.

Actually we have over 40 MB data on every 6MB Gravitic cartridge. Someone on beyond3d forum did Benchmarks on both.

Edited July 12 by agradeneu

[agradeneu]

5 hours ago, Wilheim said:

Hi!

 

Some time ago I got an Neo geo AES. I loved the games made for it! Then I thought: would be possible to port some Neo geo title to the Jaguar?

 

According to the specs, it should be possible. Maybe the sprite engine would be harder to implement. But, who knows?

 

Maybe this discussion was made before, I don’t know. But I put it on the table anyways.

Generally yes, NeoGeo games got Ported to SNES and Genesis,e.g Fatal Fury. . But I wont start an argument on that;)

[42bs]

8 minutes ago, agradeneu said:

Actually we have over 40 MB data on every 6MB Gravitic cartridge. Someone on beyond3d forum did Benchmarks on both.

If a NeoGeo game is 40MB it is likely that the unpacked data is way larger.

But hey, with JagGD, we have 12MB or even more. But then, who's gonna draw all these images?

[agradeneu]

3 minutes ago, 42bs said:

If a NeoGeo game is 40MB it is likely that the unpacked data is way larger.

But hey, with JagGD, we have 12MB or even more. But then, who's gonna draw all these images?

I dont know if Neo Geo could handle compressed data on the fly.  I doubt they used the compression ratio like we did. 16 MB Jag carts are possible too.

Edited July 12 by agradeneu

[42bs]

Why "on the fly"? The Jaguar does not support compressed data "on the fly". You always need to depack it.

 

[42bs]

1 hour ago, Ericde45 said:

and to add to this, the cartridge on NeoGeo can be read at full bus speed. there is a lot of buses in this console. so this huge capacity is also very fast, faster than jag cartridge and jag CD

 

some good reading, about neogeo, and about a lot of console, worth to be all read : https://www.copetti.org/writings/consoles/neogeo/

Looking at the specs, I doubt it. 68k@12MHz. So max. 16MB linear address space. But since 68k uses memory mapped devices, it cannot use the full address range.

 

[agradeneu]

16 minutes ago, 42bs said:

Why "on the fly"? The Jaguar does not support compressed data "on the fly". You always need to depack it.

 

Yep, that is what I meant, and now ask yourself if the NeoGeo does that if the point of those big carts is to read data directly at full speed? The Jaguar has fast RISC chips to decompress on the fly, how would you do that on NeoGeo? Just to consider.

For Gravitic vs. NeoGeo, we are comparing Apples and oranges here.

Graphics on the Neo Geo are tile based and 4 bit. Usually tiles are 16x16 size. 

On Gravitic Rom, we store large Bitmaps several screens big, in 144 colors, 1 MB for each map.

The backgrounds are bigger than 1 screen and 16 bit color, so around 300 KByte per background. Now add music and other stuff and its quite huge. Using radical compression on large gfx made it fit into a 6MB cart. A lot of people would tell it was impossible or not feasible. But it worked;)

 

Edited July 12 by agradeneu

[42bs]

Ok, checked more on the specs, with 64kb of RAM it is likely there is no compressed GFX. And since it is tile based, the GPU likely pulls it of the ROM.

But then, IMHO it would be technical possible to port certain NeoGeo games if they do not exploit all HW sprites to the Jaguar.

 

But still the question: Why should one do it? Instead of investing a lot of time in a port, better write a genuine Jaguar game.

 

Ah, wait, that's what CJ does 🙂

[agradeneu]

1 hour ago, 42bs said:

Ok, checked more on the specs, with 64kb of RAM it is likely there is no compressed GFX. And since it is tile based, the GPU likely pulls it of the ROM.

But then, IMHO it would be technical possible to port certain NeoGeo games if they do not exploit all HW sprites to the Jaguar.

 

But still the question: Why should one do it? Instead of investing a lot of time in a port, better write a genuine Jaguar game.

 

Ah, wait, that's what CJ does 🙂

Porting takes less time and manpower, than creating a new game from scratch, surely. 

The ports can be done by 1 coder, while an original game like GM took almost 3 years with 2 people working in tandem and you still need some music and sound FX. 

I worked "full time" on gfx assets and world/level design for Gravitic and Jumping. I also wrote/edited scripts for GM levels to become more interesting, edited some sound FX and so on. And then on top comes testing.

 

However, when someone makes an unofficial port of e.g. Mortal Konbat, he gets a lot of attention and support, while leveraging on graphics assets, character design, gameplay mechanics already available.

 

 

 

 

 

[42bs]

🙂

 

Porting a game from a completely different architecture?  Well, at least it has the same resolution as the Jaguar, less colors. So the gfx can like be "translated" with some tools.

But really, I doubt it is fun. And of course, porting a game means to get the license (ok, maybe I am old fashioned here) in order to sell it later.

 

Regarding MK: I think reboot games get a lot of attention.

[42bs]

3 hours ago, agradeneu said:

Yep, that is what I meant,

 

There are CPUs that can depack data on the fly while reading from ROM/RAM. Using a CPU to depack is not "on the fly".

[roots.genoa]

I don't understand why so many people still wonder why most homebrew games are ports. Most homebrew developers are programmers working alone, and they know nothing about graphics or even gameplay most of the time. A port is way easier, even though I tend to agree it's a bit useless (unless it's better than the original game for some reason)... But like agradeneu said, it gets a lot more attention than original games. Retrogaming is 90% driven by nostalgia, and unfortunately, original games are mostly ignored unless they look very impressive.

[agradeneu]

1 hour ago, 42bs said:

There are CPUs that can depack data on the fly while reading from ROM/RAM. Using a CPU to depack is not "on the fly".

"Real time data decrunch" in Native demo, DSP uncompresses data as needed. Satisfied?  

[+Biff Burgertime]

How about someone ports some Jaguar games to Neo Geo? Do you think Neo Geo could handle Bubsy?

[+Gemintronic]

A dev suite like Scorpion Engine could probably work if Jaguar was supported as a target.  I've already got one project that can compile for Genesis and Neo Geo and Neo Geo CD.

 

But, that's a lot of technical expertise and time to add a new target.  Plus, I have no idea how I'd make a Neo Geo cart for less than $100 my cost.

[Ericde45]

neo geo is able to read 40 megabytes directly from rom to display, no decompression, full display speed

jaguar is not able to display directly from rom without loosing speed

and if you add decompression, it slows it all

 

and i am sure of this because in Xenowings i decompress graphics from rom using dsp. this involves slowing the dsp to let the rom provide the datas

 

and i need to stop music because decompressing satures the dsp so the music interrupts are not all at the expected times and this bugs music.

( on jaguar, you always have a little surprise in every part of what you expect to work seamlessly )

 

and that's only the graphics size issues, if you add ym2610 thats gives FM+SSG+PCM on its own coprocessor, you're lost.

 

 

[Ericde45]

17 hours ago, 42bs said:

Looking at the specs, I doubt it. 68k@12MHz. So max. 16MB linear address space. But since 68k uses memory mapped devices, it cannot use the full address range.

 

the 68000 does not access the graphics banks of the neogeo catridge

it is only accessable by the video subsystem

[agradeneu]

On 7/13/2024 at 8:56 AM, Ericde45 said:

neo geo is able to read 40 megabytes directly from rom to display, no decompression, full display speed

jaguar is not able to display directly from rom without loosing speed

and if you add decompression, it slows it all

 

and i am sure of this because in Xenowings i decompress graphics from rom using dsp. this involves slowing the dsp to let the rom provide the datas

 

and i need to stop music because decompressing satures the dsp so the music interrupts are not all at the expected times and this bugs music.

( on jaguar, you always have a little surprise in every part of what you expect to work seamlessly )

 

and that's only the graphics size issues, if you add ym2610 thats gives FM+SSG+PCM on its own coprocessor, you're lost.

 

 

What is the max bandwidth of Neogeo when it reads from ROM? Iam asking this, because graphics are 16x16 tiles, you probably dont need huge data throughput.

And one last fact: Native demo decompresses graphics Realtime, while the game runs at 60 FPS, 16 bit Mode. So it must be fast, otherwise it would not work. Remember, you still have 2 MB RAM, so why read all gfx from ROM? 

Obviously, we are comparing apples and oranges here. By pure data througput, Jaguar beats the Neogeo easily, it reads and displays large 16 bit sprites while the NeoGeo uses tiny 16x16 tiles to render images, very efficient for tile based gfx. Totally different approach. The Jaguar was also designed for 3D graphics, so a system tailored exclusevily to tiled based graphics did not make sense to begin with. Let me say this, while we can discuss the possibilities of porting from Neogeo to Jaguar, a game like Gravitic would be almost impossible to port to Neogeo. I have made the gfx, I know the data sizes, I know the data size of a 16x16 tile in 4 bit. NeoGeo games are extremely well done artworks, sometimes its not a matter of specs, cycles and bits and bytes.

So having a discussion ruled by coders knowing little to nothing about the impact of artwork, and sadly dismissing POV from the artists,  makes me giggle a bit.

Edited July 14 by agradeneu

[42bs]

42 minutes ago, agradeneu said:

And one last fact: Native demo decompresses graphics Realtime, while the game runs at 60 FPS, 16 bit Mode. So it must be fast, otherwise it would not work. Remember, you still have 2 MB RAM, so why read all gfx from ROM? 

Native is all in RAM, so it decompresses gfx from RAM to RAM.

[42bs]

48 minutes ago, agradeneu said:

The Jaguar was also designed for 3D graphics

Writing this over and over again does not make it more true.

[agradeneu]

41 minutes ago, 42bs said:

Native is all in RAM, so it decompresses gfx from RAM to RAM.

Why dont you tell us why? Telling half the Story is not a sincere move. 

 

BTW its a really irrelevant fact. What counts is that you can store and render larger graphics data with limited RAM or ROM. And that was the point of discussion. 

Edited July 14 by agradeneu

[agradeneu]

33 minutes ago, 42bs said:

Writing this over and over again does not make it more true.

Because its true. Or dont you see the different architecture of Jaguar and NeoGeo? But please, dont argue with me, but with the Designer of Jaguar. He might be interested to hear you why he was wrong all the time but probably you would be more cautious and sincere with your discussion. 

 

Then I might ask you to build a time Machine, go back to 1992 and tell the Designers how to make a 3D graphics hardware. 

 

 

Edited July 14 by agradeneu