The animated copy is registered for the vehicle's whole position array, and a
race frame has 228 primitives that bind it. Suppressing draw merging for all of
them turned the kart's display list back into hundreds of separate draw calls,
each recorded once and replayed in the mono pass and both eyes: on a Quest 3 the
app frame went from 15.7 ms to 21.7 ms with the GPU pinned at 97 %, which past
the 72 Hz deadline reads as 56 FPS against 42.
Merging is unsafe only between draws that resolved the array differently, since
the merged whole renders through the binding of the draw it folds into. So
resolve the replacement once per draw, before the merge test, and merge into a
draw that reached the same decision. Draws of an opponent sharing the asset
merge with each other again too, and with no set registered the test is exactly
what it was before the feature.
Measured at the same place on a Quest 3: 60 FPS against 42, the app frame back
to 13.9 ms, 564 draw calls a frame with 11808 primitives merged away.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The VR first-person camera will animate the local vehicle's steering wheel
by handing Aurora a rotated copy of one of the vehicle's position arrays.
A draw picks up the copy only when it binds that exact array with the local
vehicle's position matrix (per-position ownership for indexed-matrix
draws), so opponents sharing the asset keep the original vertices. The copy
takes the same padded upload path as the original and never touches the
shared array cache.
Ported from heurazy's mario-kart-wii-VR-port (GPL-3.0-or-later).