Initial preparation for Android XR support

[matthargett]

Status — superseded (2026-07-10)

There is no remaining patch from this branch that should be merged. Replaying the PR onto current master (7e7e5db9be238b38c68d48d4c48fd45e1481399f) drops the two imported upstream PRs and the exported-activity commit as already applied; the other commits are obsolete, self-reverting, or tied to files that upstream replaced. The clean result is exactly master, so an empty force-push would add no value.

Intent already fulfilled

• [CI maintenance] Fix test installation ios/macos + misc #1550 and win32 installation #1553 contain the two upstream changes copied into this branch.
• Upgrade Android build system: AGP 8.2.1→9.0.1, Gradle 9.0→9.1, NDK r23b→r29 #1616 (454e7eed) delivered the Android build modernization: AGP 9, Gradle 9.1, Java 17, default NDK r29, compile SDK 34, ARCore 1.52, AndroidX mode, and android:exported="true".
• Address sanitizer/ndk28c JsRuntimeHost#118 (70ba1e53) delivered the NDK r28c and UTF-16/char16_t compatibility work. BabylonNative's current JsRuntimeHost pin is 44 commits ahead of that merge.
• Use GitHub action #1661 (2bb85a0e) replaced the Azure Android jobs changed here with the current GitHub Actions workflow.
• "Embedding" (simple) API layer #1701 (063244d8) supplied the current cross-platform Embedding lifecycle, including Android context/activity registration, pause/resume, runtime/view ownership, XR surface handoff, and NativeXr initialization.

Intentionally not carried forward

• The local char_traits workarounds and downstream JsRuntimeHost patch were added and then removed within this PR.
• The final JsRuntimeHost fork-branch pin is stale; remaining runtime hardening is tracked separately in [codex] Port remaining Android XR compatibility fixes JsRuntimeHost#182.
• The "system V8" search only modified Install/Test/CMakeLists.txt, which now supports Win32 only. It never changed the production Android runtime path.
• The androidXrSimulator flavor only changed ABI filtering and added no Android XR/OpenXR behavior. Android's documentation now states that the Android XR emulator does not support OpenXR apps.

Actual Android XR follow-up

Android XR support itself is not complete. The active implementation is #1766, which adds the real Android OpenXR/OpenGL ES backend, stereo swapchains, frame lifecycle, and initial Quest Touch input. It is a much better base than any code in this PR.

Before BabylonNative + NativeXr can claim correct support for Samsung Galaxy XR and XREAL Aura, #1766 still needs Android XR Gradle/manifest/loader packaging, immersive-vr versus immersive-ar blend-mode plumbing, centered viewer poses and robust runtime session loss/end handling, natural hand interaction without a controller requirement, world-understanding mappings, and physical-device validation. Galaxy XR is the first test target; Aura-specific additive-display behavior requires Aura hardware.

References: Android XR OpenXR setup, supported extensions.

[matthargett]

The Win32_x64_D3D12 job appears to fail intermittently beyond my PR due to timeouts. Let me know if there's anything else I need to do. I'm upstreaming the NDK bump and the C++20 clang compatibility fix into JsRuntimeHost , PR in progress.

[CedricGuillemet]

Hi @matthargett issue with D3D12 is fixed with #1550

[matthargett]

Hi @matthargett issue with D3D12 is fixed with #1550

Excellent, thanks! Once the JsRuntimeHost PR passes and merges, I'll pop back up to this one and remove the local patch.

[matthargett]

JSRuntimeHost PR is complete and awaiting review/merge. Once that's done, I'll update this PR to pull in that version and continue. BabylonJS/JsRuntimeHost#115

[matthargett]

Integration tested the JsRuntimeHost PR here, unit tests pass and test app works in macOS and Android Pixel 2 Android 10 simulator.

[yuripourre]

@matthargett it shows that it has conflicts.

Thank you so much for working on this feature. I hope it get merged some day!!

[matthargett]

I revisited this against current master (7e7e5db9be238b38c68d48d4c48fd45e1481399f). The semantic rebase is empty:

• the copied [CI maintenance] Fix test installation ios/macos + misc #1550 and win32 installation #1553 commits are already upstream;
• Upgrade Android build system: AGP 8.2.1→9.0.1, Gradle 9.0→9.1, NDK r23b→r29 #1616 / 454e7eed superseded the Android SDK/NDK/Gradle/Java preparation and landed android:exported="true";
• Address sanitizer/ndk28c JsRuntimeHost#118 / 70ba1e53 landed the NDK r28c and UTF-16 compatibility work, and the current BabylonNative JsRuntimeHost pin contains it;
• Use GitHub action #1661 / 2bb85a0e replaced the Azure jobs changed here with GitHub Actions;
• "Embedding" (simple) API layer #1701 / 063244d8 now provides the Android Embedding and NativeXr lifecycle integration.

The remaining branch changes should not be replayed: the char_traits and downstream JsRuntimeHost patches self-revert, the fork-branch pin is stale, the system-V8 search never touched the production Android path, and the XR flavor only changes ABI filtering.

Android XR itself is not finished. The focused continuation is #1766, which already has the real Android OpenXR/OpenGL ES backend, stereo swapchains, frame lifecycle, and initial controller input. It still needs Android XR build/manifest/loader wiring, correct VR/AR blend-mode and lifecycle behavior, natural hand input, world-understanding mappings, and Galaxy XR hardware validation; XREAL Aura needs its own additive-display hardware pass. The Android XR emulator cannot validate OpenXR apps.

Because this PR has no surviving patch and #1766 is the correct implementation base, I did not force-push an empty rebase. Closing in favor of the upstreamed work above and #1766.