06022: all pitfight sets: Pit-Fighter - Vertical gaps in the background scenes

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06022	Graphics	Minor	Always	Aug 30, 2015, 17:01	Jul 18, 2024, 13:57

Tester	rcoltrane	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows Vista/7/8 (64-bit)
Status [?]	Confirmed			Driver	atari/atarig1.cpp
Version	0.53	Fixed in Version		Build
		Fixed in Git Commit		Github Pull Request #

Summary	06022: all pitfight sets: Pit-Fighter - Vertical gaps in the background scenes
Description	There's some vertical gaps that appears on the background layer during gameplay. It's mostly noticeable during the Grudge Matches where you can see some vertical 'holes' that goes through the boat on the background and you can see the sea through these holes.
Steps To Reproduce	Just play the game until the 1st grudge match and you will spot several vertical gaps on the boat right off the bat, where you can spot the sea through these gaps.
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	all pitfight sets

Attached Files	0000.png (20,390 bytes) Aug 30, 2015, 17:01 Uploaded by rcoltrane
	pitfight3-pcb-mame-graphics-comparison-2.gif (251,378 bytes) Jul 17, 2024, 16:29 Uploaded by rcoltrane
	atari-raster-scaling-system-pat5363119.pdf (1,041,190 bytes) Jul 18, 2024, 13:56 Uploaded by rcoltrane

No.11995 NekoEd Senior Tester Aug 30, 2015, 17:33 edited on: Aug 30, 2015, 17:36	Confirmed, SDLMAME64 on Linux/x64 0.165 Additionally, there is a flash of garbage in Ty's intro in attract mode. I don't know whether or not this is related, but I'm noting it here anyway. (I've also updated the report to reflect that this is a minor bug.)
No.15924 MetalGod Senior Tester Dec 18, 2018, 12:27 edited on: Dec 18, 2018, 12:29	This is how it should look like (recorded from a pcb) 3:12
No.15937 NekoEd Senior Tester Dec 21, 2018, 04:58	Given we're not doing this perfectly, I'll leave this confirmed.
No.22193 rcoltrane Tester Jun 18, 2024, 22:42 edited on: Jun 20, 2024, 18:42	After capturing some videos of my original PCB, I discovered that the vertical gaps in the backgrounds are just the tip of the iceberg! All graphics that appear on the game's central screen are distorted. Apart from the 2 sidebars, the overlay texts/characters mugshots and the whole static forklift screen, everything else which uses the scaling system (g1 scaling hardware) is distorted when compared to the original pcb. The distortions occur in all the backgrounds, on the floor and also on the characters. It even slightly changes the position of some sprites when comparing pcb vs mame side by side, same frame. I will open a new report on this soon, since it's not about vertical gaps anymore, and will upload a screen comparison showing the very same frame one over the other..
No.22231 rcoltrane Tester Jul 17, 2024, 16:31 edited on: Jul 17, 2024, 16:35	Added an animated GIF file here comparing the real PCB versus MAME - 1st animated frame at the Grudge Match on both versions. Same inconsistencies detailed in my other report, number 08884.
No.22233 rcoltrane Tester Jul 18, 2024, 13:57	I attached here today a patent document from Atari Games which describes with great amount of details how the whole raster scaling system hardware works. This may be helpful to improve the quality of the scaling system of the atari g1 hardware emulation in MAME. The pdf file name is "atari-raster-scaling-system-pat5363119.pdf". This patent began in 1981 and was updated until 1994. Two Atari developers (Doug Snyder and Sam Lee) who were involved with the development of Pit-Fighter (and are even credited in the game) are mentioned as responsible for the patent.