swayfx-mosaic/tooling/probes/step20c-optimized-blur-cache

Optimized blur cache fixture

EXPERIMENTAL / PARTIALLY_FEASIBLE; preserved evidence, campaign closed. Read the protocol before running. Reconstruct pinned sources in one new LAB outside Git. Do not use or reset a historical saved-buffer/effects ledger. No production source, package, installed library, shader or clipping algorithm changes.

The preparation builds only; the locked ledger's offline tests must pass before the three single-mode runs. All generated protocols, binaries, private libraries, PNGs and raw logs remain in LAB. Record every failed reserved launch/action; no retry for a consumed mode. Analyze offline after owned-process/socket cleanup. The separate freeze ticket publishes this source-only historical evidence.

Execution and reconstruction

The V1 campaign is closed in /home/fy59/swayfx-mosaic-optimized-blur-_ppdud_y. C0 failed before captures through duplicate same-size background configures, without a retry. Its original clients-c0-original.c and run-c0-original.py are preserved as failed fixture evidence. The current client ACKs background configures without submitting pixels; all A/B images are runner-commanded after a persistent reservation. C1/C2 completed central cache mutation, filtered pixels, H2 stability and sampled cleanup; boundary differences remain. The verdict is PARTIALLY_FEASIBLE, architecture UNDECIDED. The freeze publishes this fixture/report without new graphical execution.

Build-only reconstruction in a fresh LAB requires the pinned project commits in a full clone, Meson/Ninja/C17, installed compatible wlroots 0.20.2/SceneFX build dependencies, Wayland scanner, and network access to the pinned SceneFX and protocol sources. No system install is used.

PYTHONDONTWRITEBYTECODE=1 python tooling/probes/step20c-optimized-blur-cache/prepare.py
PYTHONDONTWRITEBYTECODE=1 python tooling/probes/step20c-optimized-blur-cache/test-budget.py

The preparer prints LAB and builds only. It retains failed preflight source copies/logs and supports a pre-graphics preparation continuation in that LAB; Meson build continuation should use the existing build directories. The new scenefx-cache-trace.patch and sway-source-trace.patch are passive standalone deltas after the historical clip/timing/guard/presentation chain. instrument.py deterministically generates them from those sources; no preserved historical patch is rewritten. XML provenance is in protocol-provenance.json: layer-shell is pinned to wlr-protocols b010a03648b88d143236de193bddbfea0c08bc84; the retained XDG XML came from wayland-protocols 1.49 and has a fixed checked digest. Generated files remain in LAB. The current and original C clients compile separately with C17 and fatal warnings.

The already-consumed graphic invocations were run.py LAB C0, C1, C2. Do not execute them again for this ticket. The ledger at ~/swayfx-mosaic-optimized-blur-v1-budget.json is shared across clones and LABs, locks atomically and refuses a second mode run or another LAB. It has no reset/refund operation. C0's second unreserved initial image is charged and documented as a reservation-protocol deviation; numerical limits were not exceeded. A new authorized ticket must define its own protocol/budget before new graphics, rather than reset this one.

Offline analysis remains repeatable:

PYTHONDONTWRITEBYTECODE=1 python tooling/probes/step20c-optimized-blur-cache/edge-model.py "$LAB"
PYTHONDONTWRITEBYTECODE=1 python tooling/probes/step20c-optimized-blur-cache/analyze.py "$LAB"

These analyzers write derived results and manifests. Never target the closed historical LAB: use a separate offline copy/output tree. The freeze audit preserved the exact pre-freeze fixture in the external snapshot named in the report; its README is the byte-identical source-manifest input. Raw logs/PNGs and per-run executed sources stay immutable. The offline model is a hypothesis about reduced-domain sampling, not native GPU readback or a shader fix. The complete source/evidence manifest digests and validation are recorded in the report after the final analysis. Full H1 differences are retained alongside the predefined ROIs; no boundary anomaly is excluded to obtain a PASS. No PNG/native-buffer identity, all-frame damage, GPU reference release or instrumentation neutrality is claimed. Runtime directories are removed and all owned processes reaped. No production patch, package or desktop change follows.