Vulkan Mobile: Crash on Samsung Galaxy Tab S2 (SM-T813)

[theromis]

Godot version

4.0.2

System information

Android

Issue description

Sorry for declaring crash this way, but I can't get backtrace from this device, I've deployed game to google play store and it crashes on this device type, rest of androids works fine.

Steps to reproduce

Just install game from app store, ui works fine and after clicking "Play" app crashes

Minimal reproduction project

https://play.google.com/store/apps/details?id=com.lonje.jumpjump

[theromis]

This is everything what I can pull out from google play console

*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
pid: 0, tid: 6886 >>> com.lonje.jumpjump <<<

backtrace:
  #00  pc 0x00000000000a2c08  /system/vendor/lib64/hw/vulkan.msm8952.so (QglCommandBuffer::DrawIndexed(unsigned int, unsigned int, int, unsigned int, unsigned int)+72)
  #01  pc 0x0000000001c9c454  /data/app/com.lonje.jumpjump-1/lib/arm64/libgodot_android.so

[Calinou]

Which rendering method does the project use (Mobile or Compatibility)? Make sure the .mobile override for the rendering method is correctly set in the Project Settings.

I wouldn't use the Mobile rendering method when targeting Android yet, as only flagships provide acceptable performance with it (and even then, Compatibility will be much faster). Older devices like a Galaxy Tab S2 will also keep struggling with the Mobile rendering method, so you'd have to wait until these become out of the picture (probably in 2-3 years from now).

In general, devices that cannot be updated to Android 9.0 or later have pretty broken Vulkan support (because Vulkan support in general is bad on Android 7.0-8.0).

[theromis]

@Calinou yes, I'm using Mobile method, because I'm using "glow" which looks bad in Compatibility method. Performance looks appropriate, but for now seems like have to switch to Compatibility.

[theromis]

@Calinou tried Compatibility mode, but "glow" seems like not works there at all. Is it possible to run on Mobile method but with OpenGL3 only (no vulkan)?

[Zireael07]

"Mobile" stands for "Vulkan Mobile", so no.

[theromis]

@Zireael07 is there any way to run OpenGL3 only on Godot 4? This is important for mobile gaming.

[Zireael07]

@theromis That's what Compatibility mode is for.

[theromis]

@Zireael07 I thought Compatibility is OpenGL2

[Zireael07]

No, it's OpenGL 3. There's no OpenGL2 in Godot 4 anymore. You are probably getting confused because Godot 3.x used to have OpenGL2 as a low-spec offering, but currently there is almost no devices that don't support 3, so OpenGL 3 is now the low-spec option compared to Vulkan

[theromis]

@Zireael07 thank you for clarification, but why glow and gpuparicles not works in this mode

[Zireael07]

@theromis Because they aren't yet implemented in this mode (same goes for 3d shadows, incidentally). GLES3 was a very late addition to Godot 4 (very recently before beta)

[theromis]

@Zireael07 got it, will research how I can help with it.

[Calinou]

Glow isn't implemented in the Compatibility rendering method yet (there is no ETA for it). You can simulate glow to an extent using billboarded Sprite3Ds.

[theromis]

Just sharing differences between this modes.
Compatibility:

Mobile:

Compatibility:

Mobile:

Am I right, that in 2-3 years planned to not have any differences, just a little performance drop on OpenGL3 because of Vulkan threaded execution?

[Calinou]

Am I right, that in 2-3 years planned to not have any differences, just a little performance drop on OpenGL3 because of Vulkan threaded execution?

The Compatibility rendering method will remain more low-end oriented. It does not aim for feature parity with Forward Mobile.

Also, Vulkan is not necessarily faster than OpenGL. In fact, it can be a lot slower in certain scenes currently. This is also exacerbated by poor Vulkan drivers on Android, which are unfortunately common. (This comment is not exclusive to Godot – many emulators also exhibit better performance when using an OpenGL backend compared to Vulkan, especially on NVIDIA graphics cards.)

[theromis]

@Calinou this is was great explanation, thank you, I really want make godot better (at least for my game LOL) please point me where I can take glow implementation for Vulkan and I'll adopt it for OpenGL3.

Also I can see artifacts on rubics cube in compatibility mode only, is it somehow related to drivers? but probably just not optimized model.

[Calinou]

I really want make godot better (at least for my game LOL) please point me where I can take glow implementation for Vulkan and I'll adopt it for OpenGL3.

It's more complicated than that; you can't just copy-paste the implementation from a Vulkan renderer to an OpenGL-based one. See #66455.

Also I can see artifacts on rubics cube in compatibility mode only, is it somehow related to drivers? but probably just not optimized model.

Can you take a screenshot and precisely point out the artifacts?

[theromis]

@Calinou about artifact just look at it here https://user-images.githubusercontent.com/3720229/235495227-cfbf9612-cc2f-4516-85c0-5299adaddcd9.png

[Calinou]

@Calinou about artifact just look at it here user-images.githubusercontent.com/3720229/235495227-cfbf9612-cc2f-4516-85c0-5299adaddcd9.png

Can you upload a minimal reproduction project?

[theromis]

Will create tonight, about glow seems like it about FXAA #69463 (comment)
can I pull it from https://github.com/naturally-intelligent/godot-4-glow-2d ?

[theromis]

@Calinou after reboot this artifact went away, seems like my local issues.

I think Godot philosophy looses one key point, in most cases mobile developers prefer loose performance for stability, and "Compatibility mode" is very important for mobile dev, I mean having same functionality as "Mobile mode" just maybe giving some warnings/notifications you are using FXAA it will significantly slow down mobile platform but give ability to avoid linking with Vulkan.

[whendricso]

Confirmed, bug and issue found on Galaxy Tab S2.

Suggestion: default to compatibility mode renderer after the editor crashes on Android

[whendricso]

Just sharing differences between this modes. Compatibility: (screenshots removed for length) Am I right, that in 2-3 years planned to not have any differences, just a little performance drop on OpenGL3 because of Vulkan threaded execution?

I agree, we should aim to have no noticeable differences but actually achieving that ideal is quite an undertaking.

Let's focus on the fact that you can soft-lock your project (causing the editor to crash on startup) if you set your render mode to anything but "compatibility" on certain devices.

Therefore, I propose that we remedy the soft-lock situation first by opening the editor in compatibility mode by default if it crashed during the previous session, perhaps with a warning or popup

[Calinou]

Therefore, I propose that we remedy the soft-lock situation first by opening the editor in compatibility mode by default if it crashed during the previous session, perhaps with a warning or popup

The issue is that we don't have a way to detect whether the app previously crashed on Android, since we currently lack a crash handler there. Implementing an Android crash handler like we have on desktop platforms isn't trivial.