research: L118 passage-tile designs (hash-exact, no readiness gain; kept as patch)

Tagged the passage bucket: per-tile prepareSweptTubeBase dominates (0.47-0.92 s summed per view),
smooth-min second. Segment lower-bound pruning (-17% pairs) and deferred fallback floor work stayed
hash-exact but moved near-ready <3%. Still +17..+26% vs L109.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1

Standalone/Research/WorldAssemblerM3/Linux118/RunL118PassageCounters.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+"""Collect two W8 passage-tile counter profiles per owner stratum."""
+from __future__ import annotations
+
+import json
+import re
+import subprocess
+import time
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[4]
+OUT = ROOT / "Saved/Linux/l118/passage-counters"
+DATA = ROOT / "Standalone/data/owner_world.json"
+BINARY = ROOT / "Saved/Linux/l118/bin/VoxelForgeCoreHeadless-l118-clang"
+CAMERAS = {
+    0: (8.0, 16.0, -372.2626953125),
+    1: (25.8369140625, 3.19921875, -737.0),
+    2: (19.166015625, -14.2001953125, -753.3740234375),
+    3: (-20.0625, -5.068359375, -900.353515625),
+}
+FIELDS = re.compile(r"([a-zA-Z0-9_]+)=([^ ]+)")
+
+
+def rows(path: Path, tag: str) -> dict[str, dict[str, str]]:
+    result = {}
+    for line in path.read_text(encoding="utf-8", errors="replace").splitlines():
+        if line.startswith(tag + " "):
+            field = dict(FIELDS.findall(line))
+            result[field["key"]] = field
+    return result
+
+
+def run(strate: int, replicate: int) -> dict:
+    OUT.mkdir(parents=True, exist_ok=True)
+    label = f"s{strate}-w8-profile{replicate}"
+    log = OUT / f"{label}.log"
+    camera = ",".join(f"{value:.12f}" for value in CAMERAS[strate]) + ",0,0"
+    command = [
+        "taskset", "-c", "0-11", "prlimit", "--as=6442450944", "--",
+        "timeout", "1740s", str(BINARY), str(DATA),
+        "--world-assembler-prototype", "--stream-benchmark", "--stream-pipeline",
+        "--workers=8", "--clip-radius=3", "--max-clip-level=8", "--max-level=8",
+        f"--camera={camera}", "--profile-lod-work", "--profile-passage-composer",
+    ]
+    started = time.monotonic()
+    with log.open("w", encoding="utf-8") as stream:
+        result = subprocess.run(command, cwd=ROOT, stdout=stream,
+                                stderr=subprocess.STDOUT, check=False, timeout=1740)
+    if result.returncode:
+        raise SystemExit(f"passage-counter profile failed: {log}; exit={result.returncode}")
+    composer = rows(log, "[PassageComposerTile]")
+    stages = rows(log, "[CpuTileStages]")
+    selected = []
+    for key, comp in composer.items():
+        lod = int(key.rsplit("lod", 1)[1].rstrip(")"))
+        if lod > 2 or int(comp["features"]) == 0:
+            continue
+        stage = stages.get(key)
+        if stage is None:
+            raise SystemExit(f"missing CpuTileStages record for {label} {key}")
+        fallbacks = [int(value) for value in stage["sweep_exact_fallback_by_caller"].split(",")]
+        selected.append({
+            "features": int(comp["features"]),
+            "sweep_pairs": int(comp["sweep_pairs"]),
+            "sweep_bound_pruned": int(comp.get("sweep_bound_pruned", "0")),
+            "exact_fallbacks": sum(fallbacks),
+            "segment_visits": int(comp["carve_segment_visits"]),
+        })
+    total = {name: sum(item[name] for item in selected)
+             for name in ("sweep_pairs", "sweep_bound_pruned", "exact_fallbacks", "segment_visits")}
+    row = {"strate": strate, "workers": 8, "replicate": replicate,
+           "passage_tiles_lod02": len(selected), "totals": total,
+           "elapsed_s": round(time.monotonic() - started, 3),
+           "log": str(log.relative_to(ROOT))}
+    print("[L118PassageCounters] " + json.dumps(row, sort_keys=True), flush=True)
+    return row
+
+
+def main() -> int:
+    if not DATA.is_file() or not BINARY.is_file():
+        raise SystemExit("missing owner data or L118 Clang binary")
+    result = [run(strate, replicate) for strate in range(4) for replicate in (1, 2)]
+    summary = []
+    for strate in range(4):
+        group = [item for item in result if item["strate"] == strate]
+        summary.append({"strate": strate, "workers": 8, "replicates": len(group),
+                        "passage_tiles_lod02_median": sorted(
+                            row["passage_tiles_lod02"] for row in group)[len(group) // 2],
+                        "totals_mean": {name: sum(row["totals"][name] for row in group) / len(group)
+                                        for name in group[0]["totals"]}})
+    (OUT / "summary.json").write_text(
+        json.dumps({"runs": result, "summary": summary}, indent=2) + "\n",
+        encoding="utf-8")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())