switch to Angle backend for Android

[Rik Cabanier]

I'm an engineer on the Oculus browser team.

We have some custom gl additions to our browser for WebXR and Ken Russell told me that there is a group at Google working on switching to Angle for the Android version of Chrome.

Can someone tell me what the status is of that project?

I suspect that our additions require changes in Angle so that they can be passed through...

[Peng Huang]

We are finching passthrough command decoder (ANGLE) on Chrome Canary, Dev and Beta channels. Currently, there are some weird crashes with old drives with  PowerVR GPUs. Those crashes blocked launching Chrome + ANGLE. However I think Chrome 100 drops support for Android older than 6.0. So those crashes shouldn't be blocker anymore.

[Rik Cabanier]

Thanks!

So, once this is turned on, all GL commands will go through angle? Will there be a way to turn this off until we can port our changes?

Are there plans to switch out the GL backend with a vulkan one?

[Peng Huang]

You can turn off passthrough command decoder in chrome://flags page.

And vulkan is launched for Android Q and later (with some GPU blocked). When ANGLE is launched on Android, we will start working on ANGLE Vulkan backend.

[Rik Cabanier]

On Wednesday, April 13, 2022 at 8:04:42 AM UTC-7 Peng Huang wrote:

You can turn off passthrough command decoder in chrome://flags page.

And vulkan is launched for Android Q and later (with some GPU blocked). When ANGLE is launched on Android, we will start working on ANGLE Vulkan backend.

Do you have a rough timeline on when this will happen?

If chrome switches to a vulkan backend, the oculus browser needs to update its WebXR GL implementation.