Crash related to the GTN750 and VR

[DJSean 4]

Hi Guys,

Long time user of your products, so first off thanks for giving us the Garmin suite in X-Plane! 😄

Since upgrading to Vulkan I've noticed a crash surrounding the GTN750 specifically (It's the only product I have) when returning to VR on decent. 

The Scenario goes as follows:

1. Start X-Plane as per normal and load your aircraft cold and dark. In this example we'll use the Aerobask Lancair/Carenado FA50 - both have the same crash.
2. Setup the aircraft up for flight in 2d desktop mode and when ready for engines start jump into VR. (I have an Oculus Rift S)
3. Taxi, take off and climb out as per normal and above 10k I jump out of VR and back to normal 2d mode for the remainder of climb and cruise.
4. Upon setting up for arrival and hitting TOD, through about 20k I go to get back into VR - this is where the crash happens.
5. Upon putting the headset on and activating VR in X-Plane the sim will then crash. --=={This application has crashed!}==--

I've done multiple testing scenarios and have installed a fresh vanilla copy of 11.50rc3 with only the latest version of the GTN installed (2.5.27.0) and done my testing with the following result. In both the Lancair Legancy from Aerobask and the Carenado FA50 (with GTN Mod) you get a crash upon returning to VR. If I disable the GTN750 and use the inbuilt default 530 and reproduce the flight you get no crash.

I've confirmed this result in both the Lancair and Carenado FA50 and have identified the GTN750 as the culprit. Log - https://1drv.ms/t/s!Ahs-5FDJ5h5qgq8TZWoHxYya5hE4jg?e=kppsGL

Please let me know if I can be of any further assistance.

DJ

 

[DJSean 4]

Quick update with more info.

This was not an issue in 11.41 and I have tested this in both Vulkan and OpenGL with the same result, crash upon going back into VR.

[DJSean 4]

Ok I've further narrowed this down.

It is to do with popping the window out in 2D (off the panel). If you dont pop it out like I show below, you can go in/out of VR as many times as you like. If you pop it out just once and even if you close the window and go back into VR you will get a crash with this error:

Quote

0:04:11.621 E/GFX: Rebuilding offscreens for window resize: x=3296 y=1776 hdrx=3296 hdry=3552

It looks like its trying to rebuild a screen which is WAY bigger than my resolution.

I hope this offers some guidance and assistance to identify a fix for this.

[RXP 2,338]

Thank you for the detailed explanation. I'll try to repro and let you know.

However, just a few lines above:

[SASL3_TBIENT INFO]: [LUA]: "FGProline_FA50_2D"    ok
0:06:03.056 I/OVR: Initializing VR Subsystem.
0:06:03.056 I/VR: Interaxial set to -0.032250,0.032250
0:06:03.483 I/OBJ: object Resources/default scenery/sim objects/vr/holodeck/glass.obj uses blend glass but is not set to glass lighting.
0:06:03.483 I/OVR: Adding Oculus Left controller
0:06:03.483 I/JOY: REGISTER Joystick device: oculus - vr/Oculus/oculus_Left, this is a familiar device.
0:06:03.483 I/OVR: Adding Oculus Right controller
0:06:03.483 I/JOY: REGISTER Joystick device: oculus - vr/Oculus/oculus_Right, this is a familiar device.
0:06:03.483 E/GFX: Rebuilding offscreens for window resize: x=3296 y=1776 hdrx=3296 hdry=3552
0:09:39.873 I/DSF: Warning for missing scenery file: -36+151
0:09:39.889 I/DSF: Warning for missing scenery file: -36+152

This seems to indicate it is fine here (NB: these are offscreen internal buffers, not the buffers rendering into VR view).

I'm not certain this is the size which matters, maybe it is bug with the popped out window API instead.

You might want to compare: can you try popping out the default map view for example (converting the popup into popped out using the title bar buttons), and try to repro on your system without the GTN?