08275: thndrx2, thndrx2a, thndrx2j: [possible] Graphical corruption during stage 2

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08275	Graphics	Minor	Always	Mar 28, 2022, 12:51	Aug 6, 2022, 02:05

Tester	MidnightWolf	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows 10/11 (64-bit)
Status [?]	Confirmed			Driver	konami/tmnt.cpp
Version	0.241	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	08275: thndrx2, thndrx2a, thndrx2j: [possible] Graphical corruption during stage 2
Description	On Thunder Cross 2, graphical corruption appears at the bottom of the screen, whenever the screen scrolls up or down during stage 2.
Steps To Reproduce	- Start playing Thunder Cross 2 as normal. - Play stage 2 as normal. - When the route splits near the start of the level, when the screen scrolls up or down graphical corruption appears at the bottom of the screen. - When the routes converge near the end of the level, when the screen scrolls up or down, graphical corruption appears at the bottom of the screen.
Additional Information
Github Commit

Flags	Possible
Regression Version	0.219
Affected Sets / Systems	thndrx2, thndrx2a, thndrx2j

Attached Files	001.png (688,728 bytes) Mar 29, 2022, 14:52 Uploaded by MidnightWolf Bottom lines of screen scrolling up causes corruption
	002.png (753,067 bytes) Mar 29, 2022, 14:53 Uploaded by MidnightWolf
	004.png (937,350 bytes) Mar 29, 2022, 15:03 Uploaded by MidnightWolf
	005.png (929,443 bytes) Mar 29, 2022, 15:03 Uploaded by MidnightWolf
	006.png (718,405 bytes) Mar 29, 2022, 15:04 Uploaded by MidnightWolf
	007.png (694,601 bytes) Mar 29, 2022, 15:04 Uploaded by MidnightWolf

No.19964 Tafoid Administrator Mar 29, 2022, 11:55	If you are posting issue about graphics, you need to attach some screenshots as to when it happens and reference screenshots on how it is supposed to happen. Is it a regression? Did it work in MAME correctly before?
No.19965 MidnightWolf Tester Mar 29, 2022, 15:00 edited on: Mar 29, 2022, 15:13	I have checked all versions of MAME back to 0.235 Can confirm that the bug is present in 0.235, 0.236, 0.237, 0.238, 0.239, 0.240 and 0.241. I am unable to test earlier versions of MAME as i do not have them installed. Screen shots uploaded. please notice the bottom of the screen, where graphics have a scrolling error and get broken when the screen scrolls up or down where the player is forced to choose a path at the beginning of stage 2, and where paths converge before the stage 2 boss at the end of the level. I do not have any reference material of the official arcade machine, but highly doubt that this is correct behaviour. This bug does not occur in any version of FinalBurn Neo (FBNeo) emulator that i have tested.
No.19967 Tafoid Administrator Mar 29, 2022, 22:29 edited on: Mar 29, 2022, 22:33	I can confirm the behavior and a regression version - but until I can see a play of the original PCB, I will reserve full judgement. It may be excess stuff normally not seen off screen - much like the NES has a row of graphics as it scrolls up/down. Flagged as possible.
No.19968 Tafoid Administrator Mar 29, 2022, 22:47	Traced to this commit: https://github.com/mamedev/mame/commit/9c50204b231ec539f051b00e423e947721d85d6e - k052109.cpp fix/cleanup tilemap scrolls, fixes fuusenpn and MT6790 Unknown if it exposed actual PCB behavior or not which is why this is still flagged possible.
No.20421 M.A.S.H. Senior Tester Aug 1, 2022, 20:07	In MAME 0.247GIT the bug is still there. Implemented shadow configuration bits for konami/k051960.cpp: https://git.redump.net/mame/commit/?id=f5193fabfad7bc99ff8d4488de062c8de2a90ad6
No.20430 MidnightWolf Tester Aug 6, 2022, 02:05	I found some real PCB footage that somebody (not me) has uploaded to YouTube. If you skip to the 4:23 time mark, you can see that this bug does not happen on the original arcade PCB hardware.