Replaces the single shared, side-by-side swapchain (game + menu content
packed into one image, needing viewport/scissor juggling to keep the
menu's own glClear from bleeding into the game's region) with two fully
independent XrSwapchainState instances, each sized to exactly its own
content and acquired/released on its own within the same
xrBeginFrame/xrEndFrame pair - an ordinary multi-layer OpenXR setup.
The shared-swapchain design was originally adopted to work around what
looked like a Horizon OS compositor limitation with independent
swapchains, but that was diagnosed before the real root cause of the
"menu shows the game's content" bug was found (gl4es's fpe.c
unconditionally substituting its own shader onto the menu's draw call -
see README's Debugging notes). Since the actual fix routes the menu's
blit through a real, non-gl4es glBlitFramebuffer() call - orthogonal to
how many swapchains exist - splitting back onto two swapchains works
fine and removes the GL_SCISSOR_TEST workaround and sub-rectangle
offset math entirely. Confirmed on-device: both quads render correctly,
hit-testing and 90 FPS unaffected.
Also adds a visible cursor to the menu quad itself: xr_input.c now
tracks whichever hand's aim ray hits the menu each frame and forwards it
to a new MenuOverlay.nativeUpdateCursor(), which draws a small dot at
that position (composited through the same Bitmap the menu's own
content already goes through) - previously there was no visual feedback
at all showing where you were pointing before pulling the trigger.
- xr_input.c/h: an OpenXR action set (aim pose, trigger/select click, a
menu-toggle button) plus ray/quad hit-testing, and a visible
laser-pointer line drawn from the controller toward the hit point.
- xr_menu.c/h + MenuOverlay.java: a second composition-layer quad,
toggled by a controller button, showing an off-screen, never-attached
Android View tree (one "Keyboard" button so far) driven by synthetic
touch events computed from the laser ray's hit UV.
- Migrate gl4es from a prebuilt binary baked into the Docker build-image
to a vendored source snapshot (android/gl4es-src/) compiled from
source at APK build time via CMake add_subdirectory(), patched through
a new android/gl4es-patches/ (mirrors the existing engine-patches/
pattern). This was needed to track down and fix a bug hit while
building the menu: gl4es's fixed-pipeline emulation (fpe.c) was
unconditionally substituting its own shader onto the menu's draw call
(fpe_ReleventState() always sets alphafunc to a nonzero sentinel, so
its fpe_IsEmpty() check could never see the state as empty), making
the menu quad show the game's own rendering instead of its own
content. Fixed by routing the menu's blit through a real
glBlitFramebuffer() call instead of a shader-based draw, which gl4es's
fpe.c has nothing to intercept - documented in README.md's new
"Debugging notes" section.
- Renumber android/engine-patches/ to close the gap left by removing an
unrelated diagnostic-only patch, and strip investigation-journal
comments and dead diagnostic code (temporary tracing, env-var probes)
left over from finding the bug above.
- Restructure README.md into numbered sections, document every
engine/gl4es patch, add Android Studio dev/testing-cycle instructions,
and generalize Quest-specific wording to any OpenXR headset. Update
NOTICE.txt to match (gl4es is now vendored/patched source, not a
prebuilt binary; add the OpenXR-SDK loader).
ml