Taito F3 emulation progress (MAME)

[Keade]

Good news, everyone !

Taito F3 driver got improved, which fixes many bugs. https://github.com/mamedev/mame/pull/11811 passed review and got merged, which means it should be in MAME 0.266 (until then it is possible to compile from source).

Shmups that run on that system:
Ray Force / Gunlock
Space Invaders '95 : Attack Of The Lunar Loonies / Akkanvader
Space Invaders DX
Twin Cobra II / Kyukyoku Tiger II
Gekirindan
Grid Seeker : Project Storm Hammer
Darius Gaiden

[hyp36rmax]

Good news!

[copy-paster]

If this fixes the lights in Elevator Action Returns, graphical flicker glitch in Grid Seeker and some other stuff it'd be one of the greatest moment in emulation history.

[copy-paster]

Someone sent me the latest nightly build and good news, longtime-standing EAR's lights glitch has been fixed! Took them over 2 decades really




But Grid Seeker's classic 5th boss explosion glitch is still there unfortunately


Fortunately they're aware about it and said it would be fixed sometime in the near future, once they figured out of the sprite limit

[BIL]

Big news! EAR2's busted lights... or rather, non-busted lights have been a constant forever now.

[copy-paster]

Yeah F3 bros will be so back when 0.266 drops. Grid Seeker is unfortunate case but on the bright side it's also restoring another longtime missing VFX like the fadeout effect in Darius Gaiden (when you entering the 4th zones), fade-in with glow effect logo appearance in Gekirindan's title screen etc.

[Bassa-Bassa]

Do you mean this one?
https://mametesters.org/view.php?id=7776

Are these also mentioned?
https://mametesters.org/view.php?id=1923
https://mametesters.org/view.php?id=1922
https://mametesters.org/view.php?id=1924

Never thought I'd live to see a serious attempt at improving F3 emulation in Mame at this point, it was like nobody realized the importance of this system, despite its complexity.

[copy-paster]

They mentioned the third link, which said to be fixed on upcoming 0.266. Zone U glitch seems to be a common bug, even a few PCB runs on Extra 2P also have those as well.

[Rastan78]

What's the Zone U glitch?

[copy-paster]

What's the Zone U glitch?

Missing background layers for most(?) of the time, this run during Wasshoi in Tokaigi 2015 were played on a PCB and you can see the glitch in works.

MAME 0.266 is out and as promised, comes with the major code rewrite of F3 emulation which fixes majority of long-standing glitches, here are the changelogs:

Spoiler

Code: Select all

MAME Testers bugs fixed
-----------------------
- 00026: [Graphics] (taito/taito_f3.cpp) gseeker: Continue screen is completely black. (ywy)
- 01907: [Graphics] (taito/taito_f3.cpp) elvactr and clones: Stage elements are drawn over level introduction screens. (ywy)
- 01922: [Graphics] (taito/taito_f3.cpp) dariusg and clones: Persistence effects during scene transitions don’t work. (12Me21)
- 01923: [Graphics] (taito/taito_f3.cpp) dariusg and clones: Background transparency and blending effects are not applied. (ywy)
- 01924: [Graphics] (taito/taito_f3.cpp) dariusg and clones: Zone V' boss shadow is not visible. (ywy)
- 02002: [Graphics] (taito/taito_f3.cpp) elvactr and clones: Dimming effect after shooting lights doesn’t work. (ywy)
- 02097: [Graphics] (taito/taito_f3.cpp) spcinvdj: Brightness levels are incorrect for simulated cellophane overlay mode. (ywy)
- 02527: [Graphics] (taito/taito_f3.cpp) gunlock, rayforcej, rayforce: Spurious black squares appear on title screen. (12Me21)
- 02733: [Graphics] (taito/taito_f3.cpp) arabianm: Text layer is not visible during cutscenes. (ywy)
- 03741: [Graphics] (taito/taito_f3.cpp) puchicar, puchicarj: Graphics blending/transparency effects don’t work. (ywy)
- 05893: [Graphics] (taito/taito_f3.cpp) elvactr: Dimming effect after shooting lights doesn’t work. (ywy)
- 07321: [Graphics] (taito/taito_f3.cpp) bubblem, bubblemj, bubblemu: Blending effects on boss explosions don’t work. (ywy)
- 08697: [Graphics] (taito/taito_f3.cpp) kaiserknj: Vertically scaled text is drawn incorrectly. (12Me21)
Merged pull requests
--------------------
- 11811: taito/taito_f3_v.cpp: Reimplemented Taito F3 video emulation/major rewrite. [ywy, 12Me21]
-taito/taito_f3.cpp: Fixed bad iterator handling, excess semicolons, etc. [Vas Crabb]
-taito/taito_f3_v.cpp: Oprimised for performance. (#12312) [ywy]
 * Changed per-pixed blend Z buffers from array-of-structures to structure-of-arrays.
 * Allow vectorization of line blending operations.
 * Restored empty line optimization by tracking tilemap row use.
 * Consolidate sprite frame buffers (still pulls from it multiple times for each priority group).
 * Rearranged various operations to improve performance.

Unfortunately some of the long-standing glitches like Grid Seeker's 5th boss explosion glitch and missing transparency/shadows in Rayforce still present, but the contributors are aware about the issue and they said they were working on the bugfix.
Quite a massive leap in arcade emulation I'd say, given F3 alongside Konami GX emulation are considered as one tough piece of work to deal with. Rastan78 once said in STGRev discord that it took M2 a year to optimizing their F3 emulator, hence why Cozmic Collection was Switch exclusive for a year.