Input Lag guide

mediamogul

I'm personally fine with a giant disclaimer on both pages saying : UNSTABLE: ADVANCED USERS ONLY!

I'm fine with disclaimers as well, but shouldn't they read as being 'potentially unstable', given that they're also potentially stable under the right circumstances? Something akin to @Darksavior's suggestion of labeling the tweaks as simply being unsupported would remain neutral to the potential outcome, no matter what.

lilbud

@mediamogul I personally think the potentially unstable tweaks shouldn't even be on the page in the first place. Because Gods perfect idiot will come along, screw up their build using settings from the do not use section, then come to the forum kicking and screaming about how their build is screwed.

But, ya know, just my silly personal opinion.

mediamogul

@lilbud

That is one way to go. I mean, there are a few suggestions for reducing input lag listed above that are guaranteed not to cause trouble. Although games like 'Battletoads' and 'Mike Tyson's Punch-Out!!' become considerably easier with the adjustments, I'm fairly confident both games could be beaten without them given some extra practice and memorization. In fact, outside of those two examples and perhaps a few more, there's really no other situations where this is even an issue.

markwkidd

Have you all been tracking the new run-ahead lag reducer function for libretro/RetroArch cores that just debuted around the beginning of the month?

My understanding is that it should be able to shave a frame or two off of the lag for older console emulators even with low-power architectures like rpi.

mediamogul

@markwkidd said in Input Lag guide:

Have you all been tracking the new run-ahead lag reducer function

I have to say I have not, but it sounds like the cat's pajamas. I take it that this is it in action?

markwkidd

That's the very one!

caver01

@markwkidd And this wasn't an April Fool's joke?

markwkidd

@caver01 said in Input Lag guide:

@markwkidd And this wasn't an April Fool's joke?

nope, it's real. this functionality is IMO a landmark in emulation but it happened so recently that history hasn't quite noticed yet

there has been quite a bit of testing. there are likely some bugs still to be found but I think things are reasonably proven in terms of the major classic consoles and the higher performance libretro emulators for NES/Famicom, Genesis/Megadrive, SNES/Super Famicom

markwkidd

The new stable release of RetroArch 1.7.2 has been pending for weeks now because all of these major new features have hit and are still getting little bugfixes

Wait till you see what is about to hit in 1.7.3 in terms of native CRT support in RetroArch

pjft

@markwkidd I struggle to imagine that the look ahead frame improvements on RetroArch will work on the pi, as it has a non-negligible load on the CPU. But I have no facts to base that assumption on, it's just from reading the original technical release.

mediamogul

I read up on it a bit myself and it really does appear to be a tall order for the Pi. Something I found interesting is that the developer behind this feature also created PocketNES for the GameBoy Advance. In it's day, it was a technical marvel with all of it's features and Nintendo even... borrowed the code for their 'Classic NES' line of GBA releases. I'm not sure if the license permitted it, but I remember him being very upbeat about it regardless. Nice guy and a great programmer.

dankcushions

@darksavior said in Input Lag guide:

Maybe change it to unsupported tweaks or have the word "unsupported" mentioned in there.

i like this! that's good wording. i think with this change I would be happy with the rest of the updates. i think that's a good middle ground until such time as we can fully test the settings and use them as defaults for pi3+ nes.

dankcushions

@markwkidd said in Input Lag guide:

Wait till you see what is about to hit in 1.7.3 in terms of native CRT support in RetroArch

i don't think this helps retropie - pi uses a bespoke API for CRT resolutions and the current PR is only relevant to windows, right?

dankcushions

@markwkidd said in Input Lag guide:

Have you all been tracking the new run-ahead lag reducer function for libretro/RetroArch cores that just debuted around the beginning of the month?

My understanding is that it should be able to shave a frame or two off of the lag for older console emulators even with low-power architectures like rpi.

it needs 100% headroom, right? do we have any cores that have 100% headroom on a pi3 (eg, fast forward runs at 2x)?

mediamogul

@dankcushions said in Input Lag guide:

i like this! that's good wording. i think with this change I would be happy with the rest of the updates.

I reworked the headers and added a message regarding their status as specifically being unsupported on the forums. Let me know if you can think of anything else that would make this come across more clearly, and of course, feel free to change any of my wording yourself as you see fit.

markwkidd

@dankcushions said in Input Lag guide:

@markwkidd said in Input Lag guide:

Wait till you see what is about to hit in 1.7.3 in terms of native CRT support in RetroArch

i don't think this helps retropie - pi uses a bespoke API for CRT resolutions and the current PR is only relevant to windows, right?

Native RetroArch Linux support for CRTs is incoming as well. It may get broken up into a second PR or wind up as part of the original.

JasonBigham

This post is deleted!

tekn0

Im sorry for the double post but I just tested the new runahead feature on a Pi3B with the newest Retropie 4.4 and retroarch 1.7.3 compiled from source. It did make a nice difference. I was able to increase the fceumm core 2 frames, and picodrive 3-4 frames. It's awesome actually and feels really good/smooth.

Mame2003 has all types of errors, and Snes9x2010 was a nogo, even at 1 frame. All other snes cores also seemed to have issues, but fceumm and picodrive were champs and it made a noticable improvement. This was also while running crt-pi in nearest mode. The tv I tested on was not 1080p so I will have to test at that res next.

tekn0

@dankcushions The dev has said on his youtube channel he is porting retroarch crt mode to the pi and linux is already working.

pjft

@tekn0 Interesting. Full 60fps at those runahead frames sounds interesting, to say the least.

Could you test lr-genesis-plus-gx if you do have the chance?

I suppose I'll have to try that out myself then, you got me curious :)