What's the deal of Shmupmame?

[EXEXEX]

I have downloaded Shmupmame and tried it, but hey what's the difference of this build compared to the others? The GUI is pretty much like MAMEPlus and I see no difference playing some shmups, in terms of graphic, sound, etc between these two.

Though Shmupmame has a description about the autofire rate.

[Teufel_in_Blau]

Thread:
http://shmups.system11.org/viewtopic.php?t=30659

and from the official website:
https://shmupmame.wordpress.com/about/

About shmupmame:

A few months after making the MAME shmups input delay list. Pulsewidth pointed out that Raine could emulate most of the laggier games in mame with less delay, after investigation and clarification by PsikyoFan it turns out that mame emulates a frame/sprite buffer for most arcade hardware. What I found out is that this buffer can “safely” be removed on most hardware with very little consequences. So after messing around with the mame drivers for a few days I got a first version ready for release.

After a few versions I started adding more stuff in this build to make it the main (and hopefully one day the only) version of mame I will be using personally. These additional fixes include, unmamed games, improved drivers, improved audio (and audio volumes), additional display options and more input options.

In short: Less lag for a variety of different shmups but in return it *might* break some other (non-shmups) games.

Last update was 2013 tho. I don't use Mame so I can't compare the old shmuspmame with the current regular build.

[ATTRACTS]

There is absolutely a difference running certain games. Much smoother performance. For me, I notice it most on games like Feveron, Batsugun, Progear, EspRaDe etc.

[wgogh]

I recently asked myself the same question.
But then again I use Final Burn Alpha over MAME and never saw any notable difference.

[OmegaFlareX]

what's the difference of this build compared to the others?

Besides the slightly improved input response, as mentioned, it also has some features ported from ThunderMAME. Specifically, custom buttons and samples support for the Toaplan games still lacking sound (Same Same/Fire Shark etc.). Its autofire is unique among MAME builds, in that you can specify different rates for custom buttons.

The MAME source is 0.148 so any driver improvements since then will be absent (NMK sound, working Raiden 2, for instance).

[Obiwanshinobi]

When there's background scroll (that is, most of the time in your average shmup), you can see it's only sprite buffer that's got hacked out, therefore sprites are being updated a tad sooner than backdrops. Unpleasant artefact, but I found the reduced response times well worth it.
You can see how many frames game lags in MAME (and many other emulators) using step-frame method (pause emulation, then while keeping directional button pressed, emulate forward one frame at a time so you can count how many frames it takes game to respond).