The Android renderer answered each visibility test (lens-flare
occlusion) by mapping the counter buffer for its one word, and each map
waits for the GPU's queue to drain; on the Steam Frame's Zink it also
flushes and logs a performance warning. In stereo, with the flare tests
of two eyes, that took 45% of the game thread: 13-20 frames a second in
the first level's cryo bay. All counters are now read together into a
copy the first time a result is asked for after a test ends (one wait a
frame), and the same scene runs at the headset's 72.
The headset's HUD pass took the planar fog, whose animation offset only
a structure pass consumes, and the next frame's assertion stopped the
game in fogged clusters; the HUD pass leaves the fog alone.
In VR the head's turns count as looking for the scripts that wait for
the player to look (the first level's look test).
The host's thread sampler takes fractions of a second.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
