911510 - Scrolling and zooming with analog sticks on a gamepad is too sensitive

Status: RESOLVED FIXED

(Firefox for Android Graveyard :: Toolbar, defect)

Description

[Oleg Kuznetsov]

User Agent: Mozilla/5.0 (X11; Linux i686; rv:22.0) Gecko/20100101 Firefox/22.0 (Beta/Release)
Build ID: 20130624103921

Steps to reproduce:

1) Connect any gamepad to your device (in my case, it was Xbox 360 wired controller, plugged into USB OTG port)
2) Open any site in Firefox (for example, https://mozilla.org )
3) Slightly push or pull left or right stick


Actual results:

1) Firefox will start scrolling and/or zooming immediately and it won't stop unless the stick will be in a perfect vertical position (which will never happen with an used gamepad).


Expected results:

1) There is should be some threshold, otherwise it's very hard to stop scrolling/zooming, as stick's position must be perfectly vertical.
2) I expected the same behaviour as Chrome does: it doesn't start scrolling unless stick is being pushed or pulled for ~30% of it's path in any direction

Comment 1

[Oleg Kuznetsov]

Additional information: I tried it on Firefox 23 and Firefox 24 Beta from Google Play; 
My device is Asus Nexus 7 3G (first generation); Installed OS: Android 4.3 (Baseband version: 1231_0.18.0_0409; Kernel version: 3.1.10-g1e8b3d8 [e-mail] #1 Tue Jun 11 23:51:41 PDT 2013; Build Number: JWR66V)

Comment 2

[Kartikaya Gupta (email:[e-mail])]

Yeah the current implementation was only tested on an Ouya console, and so the function that checks for dead zone is hard-coded to that. Ideally we would be able to use the hardware-reported value for the deadzone but that doesn't work on the Ouya. We can probably make this value a pref though so that people can configure it differently.

http://mxr.mozilla.org/mozilla-central/source/mobile/android/base/util/GamepadUtils.java#44

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Attachment: Part 1 - Refactor code to make it more easily preffed

Comment 4

[Kartikaya Gupta (email:[e-mail])]

Attachment: Part 2 - Add a pref

Try build pending with these patches at https://tbpl.mozilla.org/?tree=Try&rev=115e27f9e0dc.

Comment 5

[Kartikaya Gupta (email:[e-mail])]

Oleg, can you install the build from http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/[e-mail]-115e27f9e0dc/try-android/fennec-26.0a1.en-US.android-arm.apk (it should show up as "Nightly" on your device, and be independent of your regular Firefox install), go to about:config and set the "ui.scrolling.gamepad_dead_zone" pref value to something larger (e.g. 100) and see if that helps with the gamepad joystick issue? Also try setting it to -1 and see if that makes a difference.

Comment 6

[Oleg Kuznetsov]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #5)
> Oleg, can you install the build from
> http://ftp.mozilla.org/pub/mozilla.org/firefox/try-builds/[e-mail]-
> 115e27f9e0dc/try-android/fennec-26.0a1.en-US.android-arm.apk (it should show
> up as "Nightly" on your device, and be independent of your regular Firefox
> install), go to about:config and set the "ui.scrolling.gamepad_dead_zone"
> pref value to something larger (e.g. 100) and see if that helps with the
> gamepad joystick issue? Also try setting it to -1 and see if that makes a
> difference.

Setting the value to "250" (or somewhere close to it) helps, while "-1" doesn't. So now I push the stick and Firefox stops scrolling when I release it. Thanks! (I hope, you're aware that this build has rendering issues during zooming)

Comment 7

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 799498 [details] [diff] [review]
Part 2 - Add a pref

I don't think we have a good consensus of what the dead zone should be to work with many devices (sample size = 2 right now) so I'm leaving the default threshold as-is, but people can twiddle it with the pref.

Comment 8

[Brian Nicholson (:bnicholson)]

Comment on attachment 799496 [details] [diff] [review]
Part 1 - Refactor code to make it more easily preffed

Review of attachment 799496 [details] [diff] [review]:
-----------------------------------------------------------------

I was about to suggest that you use hardware-detected values by default, where:
* -1 is the default pref value
* a negative value means try to calculate the hardware-detected values (like it does now), but then use some internal fallback value (e.g., 0.01) if the hardware-detected deadzone is 0
* a non-negative value overrides everything (like it does now)

This would have ideally made this code more accurate across multiple devices, but reading comment 2 and comment 6, it sounds like our hardware detection isn't reliable enough.

If this sample size of 2 is at all representative, the variance among different gamepads can be pretty huge (0.01 on Ouya; 0.25 on Xbox), so I'm concerned that it may not be possible to find a single dead zone constant that works universally. I wonder if there are other techniques we could use to try calculating a dead zone -- maybe 1-2% of the joystick's range? I guess defaulting to a preset value is good enough for now though until we're able to investigate more.

Comment 9

[Kartikaya Gupta (email:[e-mail])]

Yeah if the xbox controller in this bug had worked fine with the hardware detection I would have preferred to just default to that. But since it doesn't I'd rather keep the value we calibrated the Ouya to since I was able to verify that in person.

If we can get more data on what values work for different controllers then we can adjust the default to be a better middle ground.

https://hg.mozilla.org/integration/fx-team/rev/b3cf6b53a990
https://hg.mozilla.org/integration/fx-team/rev/d35a123d53ea

Comment 10

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/b3cf6b53a990
https://hg.mozilla.org/mozilla-central/rev/d35a123d53ea