Model 3 official emulation on Yakuza games!

[Virtua Hunter]

Hello
Congratulation for the new forum!!!

I don't know if people are aware, but Sega finally started with official Model 3 emulation on consoles, by including Daytona USA 2 and Fighting Vipers 2 inside Like a Dragon Gaiden.

For the next game Like a Dragon Infinite Wealth in 2024, there will be 3 other Model 3 games: Virtua Fighter 3 TB, Sega Bass Fishing and Spikeout.

Is it a work totally done internally by Sega, or they contacted Bart and the rest of the staff to use Supermodel emulator, sources or the know-how?
Just curious.

[Bart]

They did not contact me about it and I will definitely be taking a close look at the binary to see if there is anything awry.

[gm_matthew]

I reckon it's probably their own emulator. The 2D and 3D layers are not quite lined up perfectly (this was fixed in Supermodel years ago), and the lighting is slightly different.

Here's the game in Supermodel:



And here's the game running in Like a Dragon Gaiden:

[Ian]

I noticed some minor differences. In that scene when the guy closes the bonnet you can see a large nut in the middle of the view. In their version it's missing. In Supermodel it calculates the z range and expands it around the scene. The nut is drawn extremely close to the camera, so they must be using fixed clipping planes.

That said the texture emulation is identical to mine including the way it only draws texture lod 0 for the microtexture layer. This is extremely bespoke texturing and a quirk of the real 3d hardware that is extremely subtle. If you weren't comparing to the original with like a magnifying glass you would easily miss it.

My point is i'd be amazed if they implemented that without looking at my render code or copying and pasting it ...

I assumed this would be an actual port and not emulation.

[Bart]

I noticed some minor differences. In that scene when the guy closes the bonnet you can see a large nut in the middle of the view. In their version it's missing. In Supermodel it calculates the z range and expands it around the scene. The nut is drawn extremely close to the camera, so they must be using fixed clipping planes.

That said the texture emulation is identical to mine including the way it only draws texture lod 0 for the microtexture layer. This is extremely bespoke texturing and a quirk of the real 3d hardware that is extremely subtle. If you weren't comparing to the original with like a magnifying glass you would easily miss it.

My point is i'd be amazed if they implemented that without looking at my render code or copying and pasting it ...

I assumed this would be an actual port and not emulation.

I wonder who did the emulation for them. There is one emu dev who has done a lot of work for Sega and might have handled this. May also have been M2, which has been bringing a lot of Sega classics back to life and being a local Japanese outfit, would be a logical choice.

Looking at Supermodel is fine, since it's open source at all, but it would be pretty annoying if they copied and pasted chunks of it. I can think of a couple tell-tale signs to look for in the binary.

The micro-texturing is a good point.

[Ian]

The lighting is the 'same'. The lighting on the model3 is super simple, it's just the dot product of the light vs the normal. The issue is on the back faces the lighting can actually go negative and if you don't clamp it it can actually subtract from the ambient value, and that's what you see in Daytona. It's a deliberate choice. Some games set clamping, some games don't. They obviously never set which was which. Clamping comes from jtag .. How could you get that wrong, but implement the micro-textures the same as they work on the model3?

I did notice the tilegen code was correct. We only very recently fixed this



But .. it does make me pretty uneasy that a company has released a closed source emulator that could potentially be based upon large amounts of our code.

[Virtua Hunter]

I reckon it's probably their own emulator. The 2D and 3D layers are not quite lined up perfectly (this was fixed in Supermodel years ago), and the lighting is slightly different.

Here's the game in Supermodel:



And here's the game running in Like a Dragon Gaiden:

I had a feeling the whole image in the Like a Dragon version was too "light", so there are some differences in lighting after all.

As for the rest I hope they just created their own emulator, it would be very uncool to use supermodel code without giving even a "thanks" in the credits at least.

[Bart]

The game is available for PC right? I want to obtain it and take a peek under the hood.

[Bart]

Explain to me like I'm a 7 year old: which of these games am I supposed to buy to find the Daytona 2 mini-game?

dragon.jpg (72.96 KiB) Viewed 31176 times

[PDNEJOH]

Explain to me like I'm a 7 year old: which of these games am I supposed to buy to find the Daytona 2 mini-game?
dragon.jpg

It's the Gaiden one