Import source: web/src/lib/geometry

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

web/src/lib/geometry.ts

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+/**
+ * Arc geometry for the circular visualizations.
+ * Angles are in degrees, 0° at 12 o'clock, increasing clockwise.
+ */
+
+export interface Point {
+  x: number;
+  y: number;
+}
+
+export function polar(cx: number, cy: number, r: number, angleDeg: number): Point {
+  const a = ((angleDeg - 90) * Math.PI) / 180;
+  return { x: cx + r * Math.cos(a), y: cy + r * Math.sin(a) };
+}
+
+/**
+ * SVG path for a clockwise arc from startDeg to endDeg at radius r.
+ * Handles sweeps up to a full circle.
+ */
+export function arcPath(
+  cx: number,
+  cy: number,
+  r: number,
+  startDeg: number,
+  endDeg: number,
+): string {
+  const sweep = Math.min(endDeg - startDeg, 359.999);
+  if (sweep <= 0) return "";
+  const from = polar(cx, cy, r, startDeg);
+  const to = polar(cx, cy, r, startDeg + sweep);
+  const largeArc = sweep > 180 ? 1 : 0;
+  return `M ${from.x.toFixed(3)} ${from.y.toFixed(3)} A ${r} ${r} 0 ${largeArc} 1 ${to.x.toFixed(3)} ${to.y.toFixed(3)}`;
+}
+
+/** Circumference helper for dash-based arc animation. */
+export function circumference(r: number): number {
+  return 2 * Math.PI * r;
+}
+
+/**
+ * Maps latency to a 0..1 scale, logarithmic so both 2ms pings and
+ * 800ms page loads read meaningfully. 1ms → 0, 2500ms → 1.
+ */
+export function latencyScale(ms: number): number {
+  if (ms <= 1) return 0;
+  const v = Math.log10(ms) / Math.log10(2500);
+  return Math.min(1, Math.max(0, v));
+}