Guest swap thread blocks on real GPU delivery (NotifyGuestPresent feeds the delivery counter) + an absolute-deadline limiter at ac6_fps_target, not the vblank grid (no sub-harmonic staircase). dt-snap locks the sim delta to the exact target at steady rate (kills the shake). Guest vblank forced to free-run during gameplay so pacing needs zero config. ac6_unlock_fps is the single master switch, ON by default (folded in timing-hooks/vblank-auto/delta-precision/dt-snap-tolerance AND the flight-model framerate-independence fix).
The game builds its per-frame sim delta as floor(elapsed * 3000) + 1, capped at
100. The floor plus the +1 guard bias the delta high by (1 - frac) every frame,
which is invisible at the native 30fps (the cap absorbs it) but becomes a
systematic speed-up once the unlock frees the frame rate: about +2% at 60fps
and +10% at 300fps.
Add a hook on the delta computation that carries the fractional remainder
across frames, so the summed integer deltas track real elapsed time exactly
instead of rounding up every frame. Gated by ac6_delta_precision (default on)
and only active while the unlock's divisor remap is.
With the unlock forcing single-vblank presents, frame-locked content (menus,
hangar, in-engine cutscenes) free-runs far too fast while only gameplay should.
Pace the guest vblank dynamically: free-run only while the 3D world is being
rendered, otherwise force the native 60Hz.
"World is rendering" is detected from the GPU side - the command processor
stamps a heartbeat (NotifyWorldCompositorDraw) whenever a draw uses the
world/effects compositor pixel shader (ucode 17e5e4ac3e713245), which runs
every frame of 3D but never in the 2D front-end. The present timing hook then
sets a guest-vblank Hz override via the new GraphicsSystem hook. Only engages
under the unlock; ac6_dynamic_vblank=false restores the plain always-on unlock.
The flight model's longitudinal force/speed-command accumulator and the
accel/brake trigger command are stepped by fixed per-frame constants with no
delta, so with ac6_unlock_fps active the plane accelerates and brakes
proportionally faster at higher frame rates.
Wrap the two flight-model functions (rex_sub_823046A0 force step,
rex_sub_82329B40 input shaping) and rescale each accumulator's net per-call
change by frame_time / 33.3ms, reproducing the native 30fps continuous-time
dynamics at any frame rate. Bit-exact pass-through at <=30fps; applies to
player and AI aircraft. Gated by ac6_fps_physics_fix (default on) and only
active while the unlock's timing hooks are (ac6::TimingHooksActive).
Suspend the FPS unlock while a demo-manager Exec (DD sub_82184460 / EM sub_821856F8) ticks, so the frame-locked IngameCinematics Sequencer plays at native ~30fps instead of double speed. Adds ac6_cutscene_clamp CVar (default on).
Dipshet