Phone Flashlight not working with Vuforia

I used the Vuforia code CameraDevice.Instance.SetFlashTorchMode(true) but it always return false (and never turns the flashlight on), but my phone (iPhone SE) has flashlight and even a lantern functionality, and I couldn't find any documentation that explains this happens or how to fix it.

I didn't configure anything before calling that piece of code, I just called it. Maybe there is some initialisation required? Something like var vuforia = Vuforia.Init() or anything like this (in the Start() or Awake() methods)?

What can it be? Is there a way to fix it? Is there a better (or just another) way to turn the device's flashlight on?

Thank you!

 

This is the correct code for enabling and disabling the flash. Are you running this before initializing Vuforia?

Our Core Samples have an example of enabling and disabling this value through UI, could you review that and see if you are missing something?

 

Hey, Vuforia-Strasza, thanks for answering!

I added CameraSettings.cs (a class from Vuforia core samples) into my GameObject (just to make sure everything would be configured just like the core samples) and when I want to turn the flash on, I call the method SwitchFlashTorch. As I said before, I'm using an iPhone SE, which has flashlight and even lantern functionality.

Nothing happens though, xcode's console shows this:

Toggle flash ON FAILED
Vuforia.CameraDevice:SetFlashTorchMode(Boolean)
MyAppName.Utils.CameraSettings:SwitchFlashTorch(Boolean)
UnityEngine.Events.UnityEvent:Invoke()
UnityEngine.EventSystems.ExecuteEvents:Execute(GameObject, BaseEventData, EventFunction`1)
UnityEngine.EventSystems.StandaloneInputModule: ProcessTouchPress(PointerEventData, Boolean, Boolean)
UnityEngine.EventSystems.StandaloneInputModule: ProcessTouchEvents()
UnityEngine.EventSystems.StandaloneInputModule: Process()

No idea how to proceed... is this class (CameraSettings.cs) the only class necessary to fully initialize Vuforia? I only imported this class into my project and into my GameObject.

 

So... any news? I couldn't solve it yet

 

I'm unclear what you mean by this. Are you using only this class and no other Vuforia code? Did you look at how CameraSettings.cs is used in the context of the sample?

 

I meant: I imported only this class (CameraSettings.cs) from the core samples, no other class from the core samples was imported to my project.

I didn't look at the whole code of CameraSettings.cs, because it didn't seem to have other dependencies. The class, by itself, was successfully compiled, so I thought it would do the job all alone.

I added CameraSettings.cs as a component of an object (that deals with the camera), and when I need to turn the flashlight ON, I do GetComponent<CameraSettings>().SwitchFlashTorch(ON) from another code of this object.

 

I forgot to mention, I searched all around the core samples and couldn't find any scene where it's possible to deal with the flashlight through UI.

 

@dccoo I've tested the Core Samples in Unity 2018.1.0f2 with Vuforia 7.1.34 and the flash is working on the iPhone SE. You can access the option while running the app by double tapping the screen. This will give you options for flash, extended tracking, and front camera when available.

 

Hi @Vuforia-Strasza, I'm using Unity 2018.2.0f2 and Vuforia 7.2.24 (downloaded automatically from Unity editor) and the Vuforia.CameraDevice.SetFlashTorchMode() method seems not exists any more, but it's in the Vuforia documentation.
Can you point me please in the right direction in order to find it? I've tried switching the build platform and exploring other classes but it still not showing.
Best regards.

 

This API still exists in 7.2.X. You'll need to do CameraDevice.Instance.SetFlashTorchMode() however. This is used in the Core Samples if you'd like to see an example.

 

Thanks for the answer, I've used the interface successfully while the Vuforia camera was active, but when the vuforia camera is not working (that means i'm using some Unity WebCamTexture) the flash torch is not responding.
That's odd, but it works if your application is AR only. Sadly I'm using both, switching from one to the other, so it's useless.
Thanks again.

 

Hello @jemonsuarez,

The camera must be initialized by Vuforia in order for Vuforia APIs to control the camera. Vuforia APIs are only an abstraction of platform camera APIs. Thus, we are calling the same APIs as the platform OS.

Thanks,
Vuforia Engine Support

 

Toggle flash ON FAILED

Same issue

Unity version 2018.2.0f2
Vuforia version 8.0.10

code to turn of light
" Vuforia.CameraDevice.Instance.SetFlashTorchMode(true);" but it returns Toggle flash ON FAILED

 

Hello @junaidjoosani,

Does your device support ARCore? https://developers.google.com/ar/discover/supported-devices. If so, then this is likely Vuforia Fusion using ARCore for positional device tracking, but ARCore not supporting the torch: https://github.com/google-ar/arcore-android-sdk/issues/153

Thanks,
Vuforia Engine Support