Simulated netboard - future of linked play in Supermodel?

[MrThunderwing]

Outstanding work Matt, the last of the great Model 3 board racers now working in link-up mode I was just having a very quick check on the progress of this before going to bed, so I of course had to have a go at setting it up before hitting the sack. The link-up worked first time. One slight issue on my end I noticed is that just leaving the game to run in it's attract mode, when it got onto the mountain stage demo the cars started having a weird flickery effect. It seemed to resolve on the Snowy attract though. I can vaguely recall people mentioning in the past about SR2 having graphical issues if the PPC's too low or something, so I' not sure if it's related to that...?

[gm_matthew]

Outstanding work Matt, the last of the great Model 3 board racers now working in link-up mode I was just having a very quick check on the progress of this before going to bed, so I of course had to have a go at setting it up before hitting the sack. The link-up worked first time. One slight issue on my end I noticed is that just leaving the game to run in it's attract mode, when it got onto the mountain stage demo the cars started having a weird flickery effect. It seemed to resolve on the Snowy attract though. I can vaguely recall people mentioning in the past about SR2 having graphical issues if the PPC's too low or something, so I' not sure if it's related to that...?

Yeah, the PowerPC frequency needs to be quite high to avoid flickering on the mountain stage; I have it set to 83 MHz which seems to be enough. There's a particular edit I can make to Supermodel that drops the requirement down to 60 MHz but it would probably break some other games.

[Jiterdomer]

Maybe implement per-game settings just like MAME did. The current settings for clock speed, resolution, etc. applies to all the games.

[gm_matthew]

Maybe implement per-game settings just like MAME did. The current settings for clock speed, resolution, etc. applies to all the games.

The edit I’m referring to involves tweaking the frame timing. The way Sega Rally 2 works, it spends the first part of the frame spinning in a loop until IRQ2, which occurs 33% of the way through the frame - so it spends the first 33% of the frame doing essentially nothing.

By reducing the gap between the start of the frame and IRQ2 to 2.5%, fewer cycles are wasted and I can get the game running at full speed with just 60 MHz. But I haven’t tested this with any other games, and I’d be surprised if there weren’t at least a few that were to break.

[MrThunderwing]

Got one of my mate's to pop around this afternoon after work to give Sega Rally 2 a try in multiplayer.
https://youtu.be/5PEd-TxGuL8

[Jiterdomer]

Now the games are finally complete, I can fully enjoy LAN experience with Sega Arcade racers next to Outrun 2 SP SDX.

[segaduck]

I have tested the spike out final edition with version 864,

The performance of linked play is much better than before. Thank you gm_mathew !!!

I have tested 2~4 players linked play with multiple instances on my PC (NV 3080 GPU + AMD 5600X CPU), and I found a very interesting result to report.

(1) 2 players linked play:
As good as version 863, full speed at 60fps.
-ppc-frequency=60

(2) 3 or 4 players linked play:
The emu significantly ran in slow motion although it showed 60fps.
No matter how I changed the -ppc-frequency from 60~100, the linked play fps was still very slow and I believe it's actually around 20~30 fps.

(3) I tried to change the following parameters, the situation is the same.
VSync = 0
Throttle = 1

VSync = 1
Throttle = 0

(4) The most interesting one I've tested is,
When I changed the parameters as following:
VSync = 0
Throttle = 0

The 3~4 players linked play is running in full speed without any latency or frame-skipping in around 130~150 fps.

After that, I've tried so many different combination of parameters for a long time but I cannot find any one of them to let 4 linked-players to run in 60 fps.

[gm_matthew]

Spikeout Final Edition currently requires a hack to get it working properly; the hack was made with two players in mind so I’m pretty sure it’s the cause of in-game slowdown with three or four players.

Will upload a fix later this evening.

[Jiterdomer]

Does it make Daytona USA and Scud Race 8 player linked ran at full speed?

[segaduck]

Spikeout Final Edition currently requires a hack to get it working properly; the hack was made with two players in mind so I’m pretty sure it’s the cause of in-game slowdown with three or four players.

Will upload a fix later this evening.

Thank you so much and I am looking forward to test in the evening.