07401: salamand and clones: Sprite flickers randomly

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
07401	Graphics	Major	Always	Aug 25, 2019, 01:35	Aug 25, 2019, 10:35

Tester	jkm900	View Status	Public	Platform	MAME (Official Binary)
Assigned To	hap	Resolution	Fixed	OS	Windows 10 (64-bit)
Status [?]	Resolved			Driver	konami/nemesis.cpp
Version	0.212	Fixed in Version	0.213	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	07401: salamand and clones: Sprite flickers randomly
Description	salamand has flickers some sprite randomly now. it's regression related to bubble system updates in nemesis.cpp?
Steps To Reproduce	Start salamand Wait a minute when attract demo scene approaching
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	salamand and clones

Attached Files

No.16797 Mamesick Senior Tester Aug 25, 2019, 07:59	Regression very likely here: https://github.com/mamedev/mame/commit/e724f4d7e60c266138b1ab4ffd6cd2bb81858682#diff-a6f227c47f445e941f371c3dd4b82c85 VBLANK TIME for salamander and clones was different if compared with all other games in the driver, so probably the screen raw params are not producing the correct timings or there's something that must be changed in IRQs routines. My guess.
No.16798 hap Developer Aug 25, 2019, 09:30	It is also the only driver with VIDEO_UPDATE_AFTER_VBLANK, that's a more likely cause. If it gets sprite lag without it, maybe the hw has buffered spriteram.
No.16799 Mamesick Senior Tester Aug 25, 2019, 10:06	Commit by Kale is the cause of the bug. I just reverted it in my local source and there's no more flickering on sprites. Changing the AFTER_VBLANK thing to BEFORE_VBLANK makes the game to run really fast, FPS counter shows around 500% speed throttled. So surely there's something wrong in main IRQ routine or in the VBLANK one.
No.16800 hap Developer Aug 25, 2019, 10:16	It works fine here if i remove the video attributes flag. The only new thing I'm seeing is 1-line glitches on the left edge of the screen. But I checked youtube PCB vids of attract mode and it happens there too.
No.16801 Mamesick Senior Tester Aug 25, 2019, 10:35	Yup, I can confirm it seems fine here too. I probably made a mistake when I re-compiled nemesis.cpp for the third time to test the AFTER_VBLANK attribute. Fine it's been resolved.