00952: ssriders and clones: Characters judder when walking diagonally (possibly priority related).

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
00952	Graphics	Minor	Have not tried	Feb 7, 2008, 11:34	Sep 17, 2016, 00:30

Tester	-Misc Reporters-	View Status	Public	Platform
Assigned To	Kale	Resolution	Fixed	OS
Status [?]	Resolved			Driver	konami/tmnt.cpp
Version	0.36b4	Fixed in Version	0.178	Build
		Fixed in Git Commit		Github Pull Request #

Summary	00952: ssriders and clones: Characters judder when walking diagonally (possibly priority related).
Description	Characters judder when walking diagonally (possibly priority related). Update: The juddering isn't as severe in .72u1. Tafoid: It only seems to happen when you are walking while the screen is scrolling. If the screen is fixed, I don't notice anything but smooth movement.
Steps To Reproduce
Additional Information	Posted by Hazard / NeoGouki
Github Commit

Flags
Regression Version
Affected Sets / Systems	ssriders and clones

Attached Files	ssridersuac (state C).zip (292,301 bytes) Jun 5, 2015, 16:17 Uploaded by Pasky Save state of problem area. Simply hold right with player 3's controls to display the issue.
Attached Files	Sunset_PCB.zip (2,294,358 bytes) Jun 5, 2015, 16:18 Uploaded by Pasky Short video clip showing what actually occurs on a Sunset riders ver UAC PCB

No.00468 Tafoid Administrator Mar 29, 2008, 23:45	Flag is set for the game for "GAME_IMPERFECT_GRAPHICS". Should it be? Other than this one issue, I played through a whole game to the ending and I didn't notice anything else even resembling oddness. Any comments?
No.07293 Samurai Fox Tester Mar 6, 2011, 08:42 edited on: Mar 6, 2011, 08:46	According to NeoAlec's video, this does not happen on real hardware. The juddering is more noticeable when the character is moving downward, diagonally. In MAME, when moving downward diagonally, it seems to assume the character is moving off a series of steps or something like that, causing him to "drop" several times?
No.07302 Haze Senior Tester Mar 8, 2011, 14:32	It's probably a protection issue. The protection simulation for SSRiders is rather complex, and there are a couple of unknowns, as well as other known cases where it fails. It would be interesting to actually identify the chip and see if it's some kind of common MCU that can be dumped, or some custom programmed gate logic.
No.11714 Pasky Tester Jun 5, 2015, 16:16 edited on: Jun 5, 2015, 16:19	This issue still occurs in 0.161. I have a version 4 Player UAC PCB and can confirm the diagonal movement is still not working correctly. It can also occur when walking off a flat platform you'll do the drop animation and then be put back on the platform and eventually you'll fall down. Added a savestate for ssridersuac (MAME 64-Bit Windows v0.161) that shows the issue. Simply hold right as player 3 (bob) and you'll negotiate the slope and jitter down it. In addition I added a short video clip of the actual pcb showing how it is normally supposed to work.