The Quest offers XR_FB_hand_tracking_mesh without the app declaring hand
tracking, so a Quest 3 draws the runtime's own hand mesh rather than the
procedural gloves, and its fingers bent backwards on grip: the mesh's
joints point -Z towards the fingertip and +Y out of the back of the hand,
so flexion is negative about the joint's own X, on both hands. Fix and
test by the repository owner; OPENXR.md said the Quest always drew the
gloves, which was wrong.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
On a Quest 3 the gloves' fingers pointed up out of the fist and bent out
of the back of the hand as the grip closed: they were built along the
grip's -Z, which runs up the tube the curled fingers form towards the
thumb, and curled towards -Y, which is backwards on the right hand.
The fingers now run along Y, forwards out of the palm (+Y on the right
hand, -Y on the left, the frame being right-handed), and close towards
+X, the palm's outward normal, with the thumb on the -Z side of both
hands. A test pins the reach, the closing direction and that nothing
bends out of the back of the hand.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A stereo packet can now carry an AuroraCockpit: tracked hands and, when the
vehicle's own wheel cannot be animated, a synthetic steering wheel or
handlebar, all in metres in the seated frame. Each eye draws it inside the
scene's pass just before the first virtual-screen draw, depth-tested with
the world's own depth mapping (captured from a full-view world draw), so
the kart and track occlude the hands and the 2D layer cannot hide them.
Hands use a runtime-provided hand mesh when one is supplied and a
procedural glove otherwise.
aurora_set_stereo_scene_anchor_scaled lets the sealed frame own its world
scale: each eye's head translation is rescaled from the packet's scale to
the frame's. A non-finite cockpit is dropped with one warning; the frame
still renders.
Ported from heurazy's mario-kart-wii-VR-port (GPL-3.0-or-later).
