Application goes to sleep

LucasSoftability

Hi,

We developed an application that is meant to put items inside a vehicle.
The user places the holograms from outside and then enters the vehicle.

But it often puts the device to sleep, at least it goes out of the application and back to the shell with the moon zzz sign.

I assume that entering the vehicle makes the system believe he is in a new environment and closes the open application

Is there a way to keep the application running while entering the vehicle? Something like discarding some events run by the OS.

mark_grossnickle

It sounds like it is crashing rather than sleeping. Apps do not just sleep on their own.

I'd look into memory consumption and see if you need to unload assets between locations.

LucasSoftability

@mark_grossnickle said:
It sounds like it is crashing rather than sleeping. Apps do not just sleep on their own.

I don't think it is crashing, I managed to experience the same with another application. I tested it in our toilet (needed a confined small place) and it would close when too close to the door.

The original application does not close when running in large space.

mark_grossnickle

Perhaps map the inside of the vehicle before you start the application?

mark_grossnickle

This doesn't seem right though. I can walk around my house with an application running and not closing. The idea of getting close to a door and it closing sounds like something is off on the device or app or perhaps your device sleep settings. That isn't normal behavior.

LucasSoftability

Ok thanks for feedback. I'll check further on the device settings and see if i can create a pattern for crashing.

jbienzms

When you look at an application and see Zzz there are only a few possible reasons:

1. The application is an exclusive app (3D) and you've left it manually by doing the Bloom gesture.
2. The application is a 2D application and you already have more than the max number of 2D applications running at the same time.
3. The application is placed in your space and the device was just restarted
4. The application has crashed.

More often than not, it's reason 4 (crash). Especially during development.

I highly recommend you debug the application with Visual Studio. Don't do "Start without debugging" just click the green Play button. You'll need to have your HoloLens attached via USB or connected over WiFi.

Other tips:

• Make sure "Just my code" is turned off under debugging settings. (otherwise you won't see crashes in the toolkit)
• Make sure you're doing mixed mode debugging - Native and Managed (otherwise you won't see crashes in native libraries)

Hope that helps!

AmerAmer

take a look at you real time performance data for SoC power consumption. If the app spends too much time in the red, meaning consuming too much or the heat level is too high, Hololens will shut down/put your app to sleep to recover. Its a passive heating device and will overheat very easily if pushed.

Kalgonium

Hi,
I noticed the same behaviour and after a lot of testing (on two Hololenses) I came to this conclusion: If the cameras of the Hololens can't focus, it goes back in "trying to map your surroundings" mode and pauses the application. As soon as the cameras can see again the application goes back to where it was.
You can easily test this by putting your hands in front of the cameras ("peek-a-boo" - Hololens Edition) while an application is running.
In the performance tracing you can clearly see "Spectrum.exe" spiking and your application going idle.

It shouldn't pose too many problems, however I've noticed that Hololens is a bit "lost" once the application runs again, with the scans of the environment being slightly off (due to the fact that the user moved during the idle time, I guess).

jbienzms

however I've noticed that Hololens is a bit "lost" once the application runs again, with the scans of the environment being slightly off

This is because the Unity camera transpose is not getting updated while tracking is lost. Therefore when tracking returns the Unity "world" seems out of alignment with the physical world.

The easiest way to solve this is to use WorldAnchors and make your holograms children of those anchors. In this case when the tracking is lost and then regained you may momentarily see things out of place but the WorldAnchor will relocate itself and the holograms will lerp into their correct positions.

Kalgonium

Excellent
We'll do that, just in case !