1. tuned arrow mesh drawing

2. centralixzed arrow config in layout.py
3. seperate mesh render and display resolution to speed up (~40 fps)

examples/pipeline/profiling.py

@@ -0,0 +1,87 @@
+"""Shared stage timing helpers for finger example pipelines."""
+
+from __future__ import annotations
+
+import time
+from collections import defaultdict
+
+
+class StageProfiler:
+    """Accumulate per-stage wall times and print rolling averages."""
+
+    DEFAULT_ORDER = (
+        "capture",
+        "uv_unroll",
+        "flow",
+        "hhd",
+        "contact",
+        "read_info",
+        "pipeline",
+        "mesh",
+        "arrows",
+        "charts",
+        "display",
+        "total",
+    )
+
+    def __init__(self, *, report_every: int = 30, stage_order: tuple[str, ...] | None = None):
+        self.report_every = max(1, int(report_every))
+        self.stage_order = stage_order or self.DEFAULT_ORDER
+        self.frame_count = 0
+        self.totals: dict[str, float] = defaultdict(float)
+        self.last: dict[str, float] = {}
+
+    def record(self, name: str, ms: float) -> None:
+        self.totals[name] += ms
+        self.last[name] = ms
+
+    def tick(self) -> None:
+        self.frame_count += 1
+        if self.frame_count % self.report_every == 0:
+            self.print_report(prefix=f"[profile {self.frame_count} frames]")
+
+    def print_report(self, *, prefix: str = "[profile summary]") -> None:
+        if self.frame_count == 0:
+            return
+        n = self.frame_count
+        parts = []
+        for name in self.stage_order:
+            if name in self.totals:
+                parts.append(f"{name}={self.totals[name] / n:.2f}ms")
+        total_ms = self.totals.get("total", 0.0) / n
+        if total_ms > 0:
+            parts.append(f"fps={1000.0 / total_ms:.1f}")
+        print(f"\n{prefix} " + " | ".join(parts))
+
+
+def run_deformation_timed(tactile, *, check_motion=True, threshold=0, tail_frames=10):
+    """Run flow + gated HHD; return (flow_ms, hhd_ms). Mirrors Sensor.compute_deformation."""
+    sensor = tactile.raw_sensor
+
+    t0 = time.perf_counter()
+    sensor.compute_flow()
+    flow_ms = (time.perf_counter() - t0) * 1000.0
+
+    run_hhd = True
+    if check_motion:
+        is_motion = sensor.detect_motion(threshold=threshold)
+        try:
+            tail_frames = max(0, int(tail_frames))
+        except (TypeError, ValueError):
+            tail_frames = 0
+
+        if is_motion:
+            sensor.tail_frames_count = 0
+        elif sensor.tail_frames_count < tail_frames:
+            sensor.tail_frames_count += 1
+        else:
+            run_hhd = False
+            sensor.tail_frames_count = tail_frames
+
+    hhd_ms = 0.0
+    if run_hhd:
+        t1 = time.perf_counter()
+        sensor.compute_hhd()
+        hhd_ms = (time.perf_counter() - t1) * 1000.0
+
+    return flow_ms, hhd_ms