08568: UI issues when using GC controller hubs and pressing the analog triggers or Alt+Tab

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08568	DIP/Input	Minor	Always	Feb 23, 2023, 17:23	Feb 26, 2023, 00:54

Tester	ICEknight	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	Open	OS	Windows 10/11 (64-bit)
Status [?]	Acknowledged			Driver
Version	0.252	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	08568: UI issues when using GC controller hubs and pressing the analog triggers or Alt+Tab
Description	With a GameCube controller hub connected, even if no actual controllers are plugged in, switching between programs in Windows with Alt+Tab while in the main systems menu causes the UI to constantly switch between its different tabs. The analog C stick has its left and right directions to the "Z rotation" value which is supposed to do "UI Previous Group" and "UI Next Group" by default. This may be a calibration-related thing (there's no way to apply a deadzone to the C-Stick) but, as mentioned earlier, also happens when no controllers are plugged in. A similar effect also happens in the UI while in-game when actually plugging in a controller and pressing, then releasing the R analog trigger. L and R register as "X rotation" and "Y rotation" respectively, with values ranging from 65536 (fully pressed) to -65536 (default, fully released). In this case, it's using the "Y rotation" value for doing "UI Page UP" and "UI Page Down". In both cases, the initial R analog value and C Stick's X value are first considered their default state and thus no problematic behavior happens, but this doesn't apply anymore after switching between apps or just pressing and then depressing R.
Steps To Reproduce	Either: -Connect a GameCube controller hub. -Run MAME. -Press Alt+Tab. Or: -Connect a GameCube controller hub. -Run MAME. -Start a game. -Open the UI. -Press, then depress the R analog trigger.
Additional Information
Github Commit

Flags
Regression Version	0.252
Affected Sets / Systems

Attached Files

No.21094 Robbbert Senior Tester Feb 23, 2023, 23:29	Full screen, or windowed? Either way, I could not replicate this. All worked as it should.
No.21095 ICEknight Tester Feb 24, 2023, 02:27 edited on: Feb 24, 2023, 02:28	Full screen, tried in two very different computers and it happens in both. Didn't happen in the previous official MAME release.
No.21098 ICEknight Tester Feb 24, 2023, 20:05	Did some more testing and it only seems to happen when a GameCube controller hub is connected, even if no controllers are plugged in. This effect also happens in the UI while in-game when actually plugging in a controller and pressing, then releasing the R analog trigger. L and R register as "X rotation" and "Y rotation" respectively, with values ranging from 65536 (fully pressed) to -65536 (default, fully released), but after that value is changed it's no longer considered the default value and MAME thinks it's being pressed.
No.21099 Robbbert Senior Tester Feb 25, 2023, 12:17	I don't have any controllers so unable to try this. There were a lot of changes to controllers and inputs during the 251-252 cycle, so it's either a bug or a misunderstanding of how things work now. Hopefully the person responsible will have a look.
No.21104 cuavas Administrator Feb 25, 2023, 21:03 edited on: Feb 25, 2023, 23:21	Just manually unassign those controls if you're using one of these adapters. Rx and Ry are the right stick on Xbox, Switch and Wii U controllers in DirectInput mode. The defaults need to work with common controllers. There's no semantic information about axes available with DirectInput, so MAME has to guess where the neutral position is. It usually guesses the centre of the range, which works for stick axes and combined pedals. It tries to guess which axes are pedals for driving controls, although without any to test with, I don't know which controllers do or don't work properly. What axes does the C stick appear as with that adapter?
No.21106 cuavas Administrator Feb 25, 2023, 21:07	Actually, if Rz is the horizontal axis on the C stick, that's a completely unintuitive way of mapping the controller onto DirectInput. Logitech and PlayStation controllers have right stick vertical on Rz. I don't think it's possible to support this adapter out-of-the-box given it uses such a bizarre mapping.
No.21119 Robbbert Senior Tester Feb 25, 2023, 22:49	As a suggestion @ICEknight, have a look at cuavas's comments in MT 08569, they might apply to you too. Also, there's https://docs.mamedev.org/advanced/ctrlr_config.html although since it's undated I do not know if it takes the latest changes into account.
No.21120 cuavas Administrator Feb 25, 2023, 23:21	That docs page was updated for 0.252. And yes, using a controller config file is a good option for changing the initial assignments.
No.21121 Robbbert Senior Tester Feb 26, 2023, 00:54 edited on: Feb 26, 2023, 22:47	Just a suggestion for the docs, include the date last updated, and also the first version of mame that it applies to. I'm always confused as to whether it's up to date or not. Up to you of course.