MAMEWorld Forums - The Loony Bin - Re: I may get flamed for this, but this IS the loony bin so... (Retroarch Bounty)

> I'm starting to find your posts somewhat abrasive.
I was afraid you would think that, but no, in fact I'm simply struggling to communicate with you because you're using quantity of information to explain, some I understand, some that don't make sense to me yet no matter how hard I try. Sorry.

> In a 'best case' scenario MAME will be 1 frame more laggy than the original games due
> to having to compose the screen to a buffer for the video card to present. If you
> start turning on options that specifically add extra buffers then it will be more. If
> the game code (software) is out of sync with when your PC reads inputs / MAME gets
> inputs from your device, then there can be another, but again, that comes down to the
> software programming of the game, something MAME does not know about. PCs and
> original hardware don't work in the same way.

Yes there you're talking about what I'm trying to understand/learn.
So, you're saying that (leaving the options to buffer to sync the the display aside) there's
- at least 1 frame to compose the picture
- and maybe another one or two depending on the circumstances from things like the game software itself, or the dealing with inputs.
And that explains why some games respond the next frame, some require two, or more.

If I finally got it and that - from what I understand now - defines the base driver lag in MAME before we make things like sync options or whatever that might add more frames intervene.

And if I'm still following you it can then be radically different, and potentially higher by a few frames, from what you can experience from the real life situation (pcb + crt)

Okay then, so that information tells about the lag on the MAME side and is indeed measurable in a number of frames, which is at minimum +1

Finally all that would mean that in order to apply a realistic lag reduction that would bring the experienced delay to a realistic-enough value close to the pcb's, it would have to be based on the original hardware's live average lag measurements, and not on how much frames MAME uses, nor from an arbitrarily chosen unique number of frames reduction down to 1 frame anyway.

So in fact there isn't a single build derivative that does the best thing or they're all too random(?)
Shmupmame hacks cluelessly break the correct behaviour, frame_delay and beam racing only get us close to MAME lag (which may or may not differ a lot from the real thing) minus sync buffers, and run-ahead is used to remove a number of frames but you would first need to know how much really is good or not to remove on a game-by-game basis, which is hardly any obvious at all with the information we have, globally speaking.

So, again if I got it well, this paints a rather chaotic picture of the whole lag reduction thing.

Maybe what I was asking about would be better in the form of a consultable detailed info of the MAME chain that is running while you're playing, and translated into that number of frames we can count.
Wouldn't change the situation, but that'd still clear a number of myths and help some simply better understand what's going on during play.

Anyway I'm going to stop there because i'll probably only further increase your irritation whatever I write.

Thanks anyway, as I think I understand more on the topic now.

EDIT: okay i think I see where something went wrong in our communication; i've always thought "MAME emulates hardwares, not games", which is womething i've read a number of times in the past, so i've always thought it right to associate the two as the same thing in MAME, which is why I write 'game-hardware' for instance.
It took me a moment to realize my error, and I can say now if that if you took me literally about the 'hardware lag', if it's not the one that matter but rather the game's overall (software running on hardware) one, then of course this is the information that I value.
This is the problem when you're the layman like me, with a baggage of wrong knowledge and assumptions, while talking with developers asking them to explain complicated stuff: they're so educated that it's impossible for them to buffer their thinking and wording down to that typical low level of user talk, and both sides easily get irritated.

Yet i think this is necessary and valuable, it might be just me there, but int he end I'm convinced translating with the purpose of demythifying for the general is crucial (again because if you don't then RA & Co. will keep on winning the hearts of people, for great injustice.

> MAME isn't about playing the games anyway.

Edited by LensLarque (10/09/18 03:34 PM)