Pair is fresh only within 24 vblanks of its capture cycle; savestate/session reset already invalidate it.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Only passes that run are measured. The first passes of a race can all run in
a transient (a busy host, code run for the first time): in earlier Grand
Prix runs the three warm-up passes measured 13-15 ms against a steady 3-7 ms
at the same setting. An estimate that high prices most plans out, no pass
runs to correct it, and a plugin that crossfades while passes are shed (R4
Frame Rate) stayed on the crossfade for most or all of the run: 4, 9 and 29
passes in 22 s at 300 Hz, 7 in a verify run at 120 Hz, against about 1400
when the first passes were fast.
render_pass_cost_note_plan() (render_pass_plan.c) counts the plans that
wanted passes since the last measured pass. After 30 (about a second of a
30 Hz game) the warm-up restarts, so plans ask for one pass until three have
been measured again. When the new median is more than 3/4 of the old
estimate, the old one was right (a size that is truly too expensive, or a
host at its limit) and the next wait doubles, up to 960 plans, so these
one-pass warm-ups stay rare; a re-measure that finds the estimate stale
keeps the wait at 30. render_pass_stats reports cost_rewarms.
render_pass_plan_test covers the restart after 30 plans, an estimate that
passes keep measuring never restarting, the minimum wait after a stale
estimate, and the doubling waits when re-measures confirm the estimate
(47 ms at 4K, 10 ms re-measured as 9); render_pass_guards pins the planner's
call and its one-pass re-plan.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
render_pass_plan_phases() treated an unknown pass cost (0) as free, so the
first plans of a process scheduled every phase up to the slot cap. The
passes that allocate textures are left out of the average (up to 8 in a
row), so the first two frames ran at full count, and after an aspect or
resolution change the stale cost of the old size stayed in force. Passes
run on the emulation thread: at 4K (46.9 ms a pass) the first race frames
stalled the guest by several passes each.
- An unknown cost with a budget now plans one pass: it measures the cost
and costs the guest at most one pass per frame while it is learnt.
- The cost is a RenderPassCost (render_pass_plan.c), replacing
render_pass_cost_sample: the same allocation rule, then a warm-up of
three kept samples whose median seeds the average. Until then the
estimate is unknown. With one-pass plans a single slow first pass (a busy
host) would otherwise set the average alone, and a plan that sheds every
pass never measures again.
- The renderer keys the cost to the presented image size: a plan at
another size passes an unknown cost, and the first pass there starts the
cost over.
- RENDER_PASSES.md no longer claims passes never slow the guest, and says
a cost above every frame's budget keeps passes shed until the size
changes.
render_pass_plan_test covers the one-pass plan (none without budget), the
warm-up median (one outlier ignored; a truly expensive size still prices
itself out) and the allocation rule; render_pass_guards pins the size key.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A generation's timeline is fixed at plan time (t_len = plan period x
VBlank). When the game frame stayed up longer (a 30 Hz tick that lags to
three VBlanks, or host-interval drift), pass_gen_present expired the
generation past phase 1 + 0.5/period and the presenter fell back to its own
capture, which in FLIP mode is the frame's phase-0 image: the output ran
0 -> .25 -> .5 -> .75, stepped back to 0, then jumped to the next frame.
render_pass_gen_select() (render_pass_plan.c) now keeps render_pass_select's
hold of the newest image past phase 1 and only expires a generation after
RENDER_PASS_GEN_HOLD_MAX (4) frame lengths without a flip, i.e. a game that
stopped flipping. render_pass_stats reports late_presents (presents more
than 1/64 of a frame past its planned end). The plan keeps the plugin's
period: its phases were placed on the output deadlines of a frame of that
length, and the flip tracker's period is the previous frame's, which cannot
predict a sporadic lag.
render_pass_plan_test covers phases 1 to 4 (hold) and past 4 / NaN
(expire); render_pass_guards pins pass_gen_present to the rule.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Found in the R4 integration build at 4K (internal resolution 9x): the first
passes of a session create their image slots and backup framebuffers at
2880x2160 and cost ~70 ms; the steady passes after them cost ~10 ms. The
plan's cost average (seeded by the first sample) then sat near 20 ms, above
the ~14 ms the frame had to spare, so every later plan was shed for time --
and since a shed plan runs no pass, the average was never measured again:
Interpolated drew no in-between frame for the rest of the session.
A pass that made a pass texture or framebuffer (pass_make_color_fbo, a new
pass image slot) is no longer a cost sample: render_pass_cost_sample()
leaves it out, at most RENDER_PASS_ALLOC_SKIPS (8) in a row so the average
can never freeze on a path that allocates every pass. The time still counts
towards the frame's pass-time budget as before.
render_pass_plan_test covers the rule (allocating pass skipped, next steady
pass seeds the average, the skip cap, no counter = every pass counts);
test_render_pass_guards pins that both allocation sites count, that each
pass marks its start, and that the average goes through the rule.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- Publish an overlay DLL's pending cycles before a pass freezes the clock;
otherwise the pass's first store would publish them into the frozen clock
and the restore would drop them from the live timeline.
- The pass store policy moves into render_pass_plan.c as
render_pass_mmio_class() and gets a table test (SPU key-on, CD, timers,
SIO, MDEC and other DMA channels dropped; GP0, GP1 DMA mode/info, GPU and
OTC DMA, DICR/DPCR, I_STAT/I_MASK allowed).
- PSX_RENDER_PASS_VERIFY also hashes CD, SPU, SIO and MDEC state.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
psx_mod_render_pass_plan() / psx_mod_render_pass() let a trusted plugin
redraw its game between two logic ticks with the game's own draw code. A
pass is a sandboxed nested guest call:
- time is frozen: cycles are counted (GTE and mult/div deadlines keep
working) but no device advances, no VBlank or device event fires and no
interrupt is delivered; GPU linked-list DMA and delayed completions finish
synchronously (psx_cycles freeze, interrupts, dma);
- stores go straight to RAM/scratchpad, bypassing code-page tracking,
overlay watch and write traces; MMIO is an allow-list (GP0, GP1 DMA mode /
info, GPU and OTC DMA, I_STAT/I_MASK) and SPU, CD, timer and other device
stores are dropped and counted (memory.c);
- afterwards CPU (with the GTE), RAM, scratchpad, I-cache tags, interrupt,
timer, DMA and GPU registers are restored exactly (render_pass.c, a GPU
register checkpoint without savestate side effects), with a guest-cycle
watchdog that rolls a runaway pass back;
- on OpenGL the declared display rect (hr colour + mask stencil, raw mirror,
native-wide band, CPU VRAM rows) is backed up, drawn, captured and rolled
back; writes outside it are journaled and restored, or refused.
The presenter keeps two generations of images (the game's own frame plus
one image per pass phase), promotes one when the flip-aware source sees the
display flip to its rect, and shows the newest image at each output
deadline's phase, crossfading across gaps when passes were shed. Presents
that fall due while passes run are made between them. The plan predicts the
output deadlines of the coming frame and sheds passes to fit a host-time
budget learnt from the presenter's idle time (PSX_RENDER_PASS_BUDGET).
PSX_MOD_FRAME_INTERPOLATION_HOLD repeats the newest frame where no pass
image applies, so a pass-driven title never shows anything later than stock.
Default off: nothing runs unless a plugin calls the API, and the plan
refuses in netplay, rollback, rewind, turbo, self-check resimulation, while
suspended (FMV) or without GL flip-aware interpolation. Pass writes are kept
out of frame_fingerprint. Debug: render_pass_stats, render_pass_dump,
PSX_RENDER_PASS_VERIFY=1 (state + VRAM hashes around every pass).
The freeze API lives in the runtime-only psx_cycle_freeze.h. psx_cycles.h is
part of the overlay codegen hash and stays byte-identical, so titles that
never use passes keep their overlay caches and savestates.
Tests: render_pass_plan_test (deadline-exact phases per rate, shedding,
selection), render_pass_freeze_test (10^6 frozen cycles, exact restore,
watchdog), render_pass_guards (sandbox choke points; the codegen-hashed headers stay
free of the pass API).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Matthew Stanley