08310: cpc464 and clones [007tld]: Erratic horizon line in 007 The Living Daylights

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08310	Graphics	Minor	Always	May 6, 2022, 17:19	Sep 12, 2023, 17:16

Tester	ICEknight	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows 10/11 (64-bit)
Status [?]	Confirmed			Driver	amstrad/amstrad.cpp
Version	0.243	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	08310: cpc464 and clones [007tld]: Erratic horizon line in 007 The Living Daylights
Description	This game changes the used palette for the horizon line in every level, but said line constantly bobs up and down in current versions.
Steps To Reproduce	mame cpc6128 -flop1 007tld Load the game with: RUN"DISC or \|CPM or mame cpc464 -cass 007ltd Load the game with: RUN" Then press space to start the game
Additional Information
Github Commit

Flags	Verified with Original
Regression Version
Affected Sets / Systems	cpc464 and clones [007tld]

Attached Files	cpc living daylights bug.gif (18,775 bytes) May 6, 2022, 17:19 Uploaded by ICEknight horizon line bug

No.20186 Tafoid Administrator May 16, 2022, 22:41	I could not get the "\|" key to type nor did I find it in the emulated computer key assignments in the TAB menu. I did confirm the line using the machine/disk image and instructions above.
No.20191 StHiryu Tester May 16, 2022, 23:30	That key is the one at the right of "p", if I remember well.
No.21748 holub Tester Sep 11, 2023, 12:51	It must be imperfect timings of screen position. If anybody knows good tests which check it I can revalidate and adjust
No.21755 Haze Senior Tester Sep 12, 2023, 17:16 edited on: Sep 12, 2023, 19:37	There are many things wrong with the CPC driver in terms of timings to be fair, it's in a far more embarrassing state than the Speccy was before you picked it up, with almost every game that relies on the more advanced CRTC tricks failing in some way. None of the more advanced cases such as Super Edge Grinder, Imperial Dream, Super Cauldron, Pinball Dreams, Alcon 2020 etc. work properly (the latter seems to work, but crashes after a while) and even the more basic ones have severe issues. There are screen positioning issues even with ones otherwise not pushing too hard such as the recent Scramble port. Beyond that, the issues with things like Dick Tracy on the GX4000 where 'flipped' sprites are invisible could come down to some timing issue too, as nobody I talked to had ever seen that on an emulator outside of MAME, maybe because their base CPC emulation was far better by the time they added GX/Plus support. I would strongly recommend reaching out to the authors of the existing CPC emulators and see if they're willing to provide the best test cases and knowledge, because emulators from 20 years ago are doing a better job than MAME by a considerable margin. Those people are more likely to know the ins and outs than I do, although in the past when people from that community have come forward wanting to improve MAME they've instantly been put off the structure of MAME, the requirement to use our 6845 device, screen device, and the insanity of the floppy system (plus us basically saying the .dsk format is trash and won't be extended to support the current standards there)