Build Your Own Arcade Controls Forum

Software Support => GroovyMAME => Topic started by: donluca on November 16, 2015, 10:42:31 am

Title: Yet another thread about Neo Geo resolution...
Post by: donluca on November 16, 2015, 10:42:31 am

I'm pretty sure everyone is sick everytime they see a thread about the Neo Geo Res, but anyway... :P

I've read countless threads about the issues on Neo Geo and understood more or less all the tradeoffs made by MAME.

One thing though I don't understand: after making the various resolution modes with VMMaker, I realized there's only one at 320x224 with a vertical refresh of 59,952Hz, but the Neo Geo one is quite far from that, at 59,185Hz.

Also, I've noticed that despite telling VMMaker to make up to 200 modes (using XP with catalyst 6.5 and a X300 SE), it only makes 144.
Why doesn't it take advantage of all the slots available?
And is there a way to add a custom resolution for the Neo Geo to make it match its original vertical refresh better?

Thanks!

EDIT - replying to myself to my first question: it doesn't take all the slots available because of Yres_round, which rounds the vertical resolution to make less modes.

EDIT 2 - partially replying to my other question: from VMMaker.ini it looks like that the vref is (almost?) completely disregarded when generating modelines. I understand that it has been done to prevent having too many modelines but shouldn't vref be more important when speaking of emulation accuracy?
I mean... you can always add a couple of blank lines to have less resolutions around (this already happens if I'm not mistaken) so why not put something like a "vref tolerance" where vref with more than, say, 0.50000hz difference get their own modeline?
Just throwing some ideas around.

Title: Re: Yet another thread about Neo Geo resolution...
Post by: Calamity on November 16, 2015, 11:32:38 am

That's because by default VMMaker uses a dynamic mode table, meant to be used in combination with GroovyMAME, which will then override the default 60 Hz refresh with the right one. Check this: http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=327#p327 (http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=327#p327)

Title: Re: Yet another thread about Neo Geo resolution...
Post by: donluca on November 16, 2015, 01:07:36 pm

Ahhh so the modelines created with VMMaker are only needed to tell GroovyMAME the exact resolution of the game and then GM reads from MAME the exact vref and sets it. Neat!

Thanks for explaining and the link, it all makes sense now! :)