Twist to flip front/back camera feature missing

hemlockiv

GrapheneOS is missing the stock Pixel feature "Twist to flip camera", which switches the front-facing vs back-facing camera when the user shakes the phone while in the camera app. Normally, this setting could be found in Settings > System > Languages & input > Advanced > Flip camera, but in GOS it is absent. This corresponds to the Secure Settings key camera_double_twist_to_flip_enabled, but setting this key manually to 1 (i.e. by executing settings put secure camera_double_twist_to_flip_enabled 1 in a secure shell like ADB) has no effect, even when Google Camera is set to be the default camera app.

The "twist to flip" feature is simple and useful. This would be true if it worked in Graphene Camera, but even if the dev team decides not to integrate it, there's no reason that it should not work in Google Camera, which many Graphene users do use.

Am I missing some nonobvious setting to make this feature start working? Otherwise, doesn't it seem like an easy win to add it to GOS?

unwat

hemlockiv

I sort of checked this out. Assuming this code is what enables it, just changing the setting you did via ADB should do the trick.

If it's still not working after you changed that setting, I can only imagine it's not working for a number of reasons. I don't know enough about this stuff to know for sure. Could be that proprietary code is missing or that some changes would have to be made in GrapheneOS for it to work. Maybe GCam needs to have privileged access to read the setting and the functionality is built in to GCam. Not sure.

Getting this to work on GrapheneOS would take some work. Someone in the community would have to do the research, make the right changes, and likely write their own implementation. It doesn't appear to be a simple enableTwistToFlip = true kind of thing.

Anyway, in case you didn't see these two before, here are a couple of related links: related forum thread and related issue.

hemlockiv

unwat Assuming this code is what enables it, just changing the setting you did via ADB should do the trick

You would think so! When I ran the command to modify the setting value, though it didn't change. It remained at 0. If you have a second, I'd actually really appreciate if you ran settings put secure camera_double_twist_to_flip_enabled 1; settings get secure camera_double_twist_to_flip_enabled and see what the output is. (I'd like to rule out it just being some issue on my end)

Maybe GCam needs to have privileged access to read the setting and the functionality is built in to GCam. Not sure.

Reading a secure setting doesn't require any elevated permission, though. And the "shake" gesture is one of the default recognized gestures through the Sensors API, so it doesn't require any specialized code to listen to. (As it is, I already have a workaround via Macrodroid that basically auto-taps the camera-switcher button when Gcam is focused and a shake gesture is received. But it would be nice to do it natively.) Also, if the functionality is partly built into Gcam, you would also expect it to work when Gcam is installed.

It doesn't appear to be a simple enableTwistToFlip = true kind of thing.

I suppose so. My goal in posting here was to hope that it was that simple of a thing, lol.

in case you didn't see these two before, here are a couple of related links: related forum thread

Thanks for linking, though I'm not sure it's relevant. As discussed there, unlike the shake gesture, the back-tap gesture is a proprietary Google API that KieronQuinn had to reverse-engineer from scratch. Btw, check out the username of the last person who commented in that forum thread ;)

unwat

hemlockiv Btw, check out the username of the last person who commented in that forum thread ;)

haha. That's hilarious. I should probably check who participated in a thread I link before doing so.

hemlockiv Reading a secure setting doesn't require any elevated permission, though.

Interesting. I guess I just read "secure" and figured nothing had access to it. I never tried to access a secure setting from anything I've written. Another hilarious thing. You'd expect I would have known this since it's right there in the documentation, right at the top of the page. This is why I like this forum, can always learn something new from the community, or when someone asks a weird question and I start digging.

hemlockiv If you have a second, I'd actually really appreciate if you ran settings put secure camera_double_twist_to_flip_enabled 1; settings get secure camera_double_twist_to_flip_enabled and see what the output is.

Worked for me.

oriole:/ $ settings put secure camera_double_twist_to_flip_enabled 1
oriole:/ $ settings get secure camera_double_twist_to_flip_enabled
1

hemlockiv It doesn't appear to be a simple enableTwistToFlip = true kind of thing.

I suppose so. My goal in posting here was to hope that it was that simple of a thing, lol.

Uh. So I dismissed it as a possibility, but since I learned something new, I went ahead and tried GCam after setting this, and it works. My camera flips when camera_double_twist_to_flip_enabled is set to 1 and doesn't flip when set to 0. It does appear to be as easy as setting something to true. This makes the Settings code I was reading make a LOT more sense than it did previously.

Don't know why yours isn't working still. Maybe try adding --user [user id] to your command if using another user? Because check this out:

oriole:/ $ settings put secure camera_double_twist_to_flip_enabled 1
oriole:/ $ settings get secure --user 11 camera_double_twist_to_flip_enabled
null
oriole:/ $ settings get secure --user 10 camera_double_twist_to_flip_enabled
1

btw, I did add --user 10 to enable before, but never did that for user 11. User 11 really is an enabled user on my phone.

hemlockiv

Well this is a fascinating development. I think I had already tried adding the user parameter but I'll try it again. I wonder if it could possibly have anything to do with the fact that I had Gcam installed already, whereas you said you installed it afterwards? I can try uninstalling it then running the command again. I also noticed you're on Oriole; I'm on Panther (P7) so I wonder if that could possibly make a difference.

Just to check, does the toggle at Settings > System > Languages & input > Advanced > Flip camera exist for you?

unwat

hemlockiv whereas you said you installed it afterwards?

Oh. No. I guess what I said was unclear. I just tried it out after changing the setting. I've had GCam on my phone for a long time.

hemlockiv Just to check, does the toggle at Settings > System > Languages & input > Advanced > Flip camera exist for you?

This is a thing I've been confused about. This option was in Settings > System > Gestures on my old phone. I don't see it on my phone now, nor do I see it in the location you said. I don't even see the advanced option.

hemlockiv

unwat This is a thing I've been confused about.

I have to admit, I found this settings location from an article online. I don't remember where the toggle had been on my old stock Pixel.

settings get secure --user 10 camera_double_twist_to_flip_enabled 1

So. If I run the above, the output does change to,1 for user 10. However, the shake feature in Gcam still does not work.

If I run it with --user 0 instead (this is the default user, right?), the outputs for user 0 and for no user specified both remain 0, and the Gcam feature still doesn't work. (I'm on the default phone owner profile. It has a Work Profile too, but Gcam is installed on the Personal Profile side. I have no user user profiles active.)

unwat

hemlockiv

Maybe see what users are active by doing pm list users (I hope I remember that correctly). You can see if more than one is listed and try enabling one by one? Some commands support all users but I'm not at my computer so I can't check.

I think work profiles have their own profile account number. Maybe that's affecting it somehow? Makes no sense that mine changes and remains that way but yours doesn't.

Yeah, owner is user 0.

Have you gotten this to work before? I'll admit I tried it back when I had my old locked phone. I could never get the gesture to work. But I could this time. Seems GCam is very finniky about how the phone is rotated.

hemlockiv

pm list users returns user 0 (personal) and user 10 (work), as expected.

unwat Have you gotten this to work before?

On Graphene, no. Every Pixel phone (with stock Pixel OS) I've ever encountered has had this feature work right out of the box. I'm relatively new to Graphene, and I just recently noticed the shake-to-flip didn't work in Gcam, so I came here to investigate.

hemlockiv

Ok now this is actually getting frustrating. I decided to pull out the big guns (aka reboot into Safe Mode). ADB shell from computer, apply the setting, and it accepts it. get output is now 1. Success! ...success, right? Reboot into regular mode: setting is reset to 0. What the hell

unwat

hemlockiv

Very strange. I reset my phone to see if the setting persisted and it did.

Maybe try deleting then setting again setting 1 to default?

settings delete --user 0 secure camera_double_twist_to_flip_enabled
settings delete --user 10 secure camera_double_twist_to_flip_enabled

settings put --user 0 secure camera_double_twist_to_flip_enabled 1 default
settings put --user 10 secure camera_double_twist_to_flip_enabled 1 default

Or there's another way to set settings. Not sure if the settings command does this stuff internally or if this is different somehow. Maybe you can try this way too?

oriole:/ $ content delete --uri content://settings/secure --where "name='camera_double_twist_to_flip_enabled'"
oriole:/ $ settings get secure camera_double_twist_to_flip_enabled
null
oriole:/ $ content insert --uri content://settings/secure --bind name:s:camera_double_twist_to_flip_enabled --bind value:s:1
oriole:/ $ settings get secure camera_double_twist_to_flip_enabled
1

hemlockiv

unwat Neither of those worked unfortunately. In fact, the content delete command failed; checking the value with get still returned 0 instead of null.

Graphite Yes, I do. (Even if that were hilariously the problem, it wouldn't explain why I can't set the keys via ADB)

This is so strange. I really don't want to factory reset my phone... I can't think of anything unusual about how I had set it up where there might be an app or system thing interfering. When I mess with Dev settings, it's usually to do something specific that I'm familiar with, e.g. enabling USB debug or disabling always-on mobile data. I can't think of anything that would interfere with this random setting.

I think I'll try disabling all Accessibility services. Will report back. @unwat I appreciate your dedication and creativity with helping me investigate this issue!!

Graphite

Long shot, but you've granted Sensors Permissions right?

unwat

hemlockiv the content delete command failed

Really? What error did you get? So far, it seems like something is either quietly failing or changing the value back, so I'm wondering if this error message is useful, but you didn't share it with us, so I'm assuming it's a useless or generic error.

BTW, have you tried getting checking logcat to see if there's any useful info there? I'd personally try settings put, then delete, then content insert, then delete, then get the logs. There has to be an explanation as to why it works for me, but not for you. We have the same OS and version (probably).

hemlockiv I appreciate your dedication and creativity with helping me investigate this issue!!
hemlockiv This is so strange.

No problem. I like the strange issues. I'm curious what's going on.

hemlockiv

By jove, I've done it!

I was going through my apps one by one disabling anything that could possibly affect system settings, until I got to SystemUI Tuner. If you're not familiar, this app is a convenient gui for a lot of settings that are otherwise only accessible via shell. It's also pretty good at what it does; one time when I couldn't connect to my PC via USB for file transfer, I realized I had used this app to keep USB Debugging active persistently, which meant I couldn't change the USB mode. Well, in SystemUI Tuner there are some "Camera settings." Some of them, like the camera lock-button shortcut, were toggled on, but one—the vaguely define "Flip phone back and forth"—was not. And I guess because I'd set some of the other toggles to On, this one (which I presume is Off by default) also behaved as if it's value had been set intentionally. I toggled it on, and voilà! Mystery solved.

P.S. @unwat your idea of checking logcat was a good one, and if I hadn't just solved it, that probably would have done the trick.

Good work team, good game, hit the showers. Lunch is on me.