feat(joystick): add support for Android gamepad features

[ThomasKuehne]

here be dragons - diverse tests required, USB HID support is sometimes ... picky

enhancements to the USB joystick - all Google mandated features for Android gamepads, except for the back key, are supported

• new sim axis Accelerator (Acc), Break (Brk) and Steering (Steer)
• new sim axis D-pad (dpad) also known as HAT switch
• new joystick circular cutout mode "X-Y, Z-rZ"
• mixing physical axis and sim axis now works
• buttons are sparse - no need to configure buttons 0-5 if you only need button 6 or do remapping on the host

For Android use the USB Joystick Mode "Advanced" with "If.mode" Gamepad:

EdgeTX	Android	Linux	USB HID
axis X	left axis X	ABS_X	X
axis Y	left axis Y	ABS_Y	Y
axis Z	left axis X	ABS_Z	Z
axis rotZ	left axis Y	ABS_RZ	Rz
sim Acc 1	right trigger	ABS_GAS	Accelerator
sim Brk 1	left trigger	ABS_BRAKE	Break
sim HAT 2	D-pad	ABS_HAT0X / ABS_HAT0Y	Hat Switch
button 0	A	BTN_SOUTH	Button 1
button 1	B	BTN_EAST	Button 2
button 2	C 3	BTN_C	Button 3
button 3	X	BTN_NORTH	Button 4
button 4	Y	BTN_WEST	Button 5
button 5	Z 3	BTN_Z	Button 6
button 6	left shoulder button	BTN_TL	Button 7
button 7	right shoulder button	BTN_TR	Button 8
button 8	L2 3	BTN_TL2	Button 9
button 9	R2 3	BTN_TR2	Button 10
button 10	select 3	BTN_SELECT	Button 11
button 11	start 3	BTN_START	Button 12
button 12	mode 3	BTN_MODE	Button 13
button 13	left stick click	BTN_THUMBL	Buton 14
button 14	right stick click	BTN_THUMBR	Button 15

notes:

• translation work required
  • TR_VUSBJOYSTICK_CH_SIM has 4 additional values for the new axis
  • TR_VUSBJOYSTICK_CIRC_COUTOUT has 1 additional value for the new circular cutout mode
• button numbering between EdgeTX and the USB HID standard is off by one, resolving that would likely be a breaking change in the UI
• is based on the battery capacity pull request feat: add battery level reporting to USB HID joystick #4602

Footnotes

1. triggers - check Update contribute-to-the-user-manual.md edgetx-user-manual#11 how to feed these half axis ↩ ↩²

2. D-pad - check Update contribute-to-the-user-manual.md edgetx-user-manual#11 how to feed this special axis ↩

3. these do work on most Android devices, however their support isn't mandatory ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

[ulfhedlund]

SE translation:
#define TR_VUSBJOYSTICK_CH_SIM "Ske","Hjd","Rod","Gas", "Acc", "Brms", "Styr","dpad"

[ThomasKuehne]

Suggested layouts for tests:

channel	Android	Betaflight	Dualsense	EdgeTX pre 2.9	EdgeTX Classic
CH1	axis X	axis X	axis X	axis X	axis X
CH2	axis Y	axis Y	axis Y	axis Y	axis Y
CH3	axis Z	axis Z	axis Z	axis Z	axis Z
CH4	axis rotZ	axis rotX	axis rotZ	axis rotX	axis rotX
CH5	sim Brk	axis rotZ	axis rotX	axis rotY	axis rotY
CH6	sim Acc	axis rotY	axis rotY	axis rotZ	axis rotZ
CH7	-	axis Slider	-	axis Slider	axis Slider
CH8	sim Dpad	axis Dial	sim Dpad	axis Slider	axis Dial
CH9	button 0	button 0	button 0	button 0	button 0
CH10	button 1	button 1	button 1	button 1	button 1
CH11	-	button 2	button 2	button 2	button 2
CH12	button 3	button 3	button 3	button 3	button 3
CH13	button 4	button 4	button 4	button 4	button 4
CH14	-	button 5	button 5	button 5	button 5
CH15	button 6	button 6	button 6	button 6	button 6
CH16	button 7	button 7	button 7	button 7	button 7
CH17	button 8	-	button 8	button 8	button 8
CH18	button 9	-	button 9	button 9	button 9
CH19	button 10	-	button 10	button 10	button 10
CH20	button 11	-	button 11	button 11	button 11
CH21	button 12	-	button 12	button 12	button 12
CH22	button 13	-	button 13	button 13	button 13
CH23	button 14	-	button 14	button 14	button 14
CH24	-	-	-	button 8POS (15-23)	button 8POS (15-23)

Stick to the order the axis are declared. Applications are supposed to read axis IDs however many do not and use different kinds of position index instead.

Similar layouts:

other controller	use layout
OpenTX	EdgeTX pre 2.9
Orqa FPV.Ctrl	EdgeTX pre 2.9
Stadia	Android - use buttons 0-1, 3-4, 6-7, 10-14 and 16-19
Xbox	Android - use buttons 0-14

[ThomasKuehne]

Items resolved during compability testing:

1. dpad axis was displaced by about 0.5%
2. the sim Steering axis is commonly supported on Linux and on some Android devices
3. an additional circular cutout mode "X-Y, Z-rZ" was needed

Anybody else finding functional items gets a cookie 🍪

[ThomasKuehne]

Sorry for that - commit history is now squashed and without any merge commits.

[pfeerick]

Don't stress over it too much... that's why I said "where possible". As rebasing after having done merge commits can be messy and prone to things going wrong. So IMO not is worth the hassle if PR is otherwise self-contained and doesn't conflict.

…

On Sat, 6 Apr 2024, 6:37 am ThomasKuehne, ***@***.***> wrote: Sorry for that - commit history is now squashed and without any merge commits. — Reply to this email directly, view it on GitHub <#4626 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABJ66KIFIHNKOYIPG3GG57LY34DQBAVCNFSM6AAAAABDDWCKNCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANBQGU4TIMRTGY> . You are receiving this because your review was requested.Message ID: ***@***.***>

[ThomasKuehne]

No worries.
The cause for the initial merge approach were the concurrent translation updates - especially Portuguese and Ukrainian - leading to merge conflicts.