3.3

Added pets profile

assets/js/physics.js

@@ -526,40 +526,51 @@ export function calcShadeAirTemp(Ta, effectiveRad, va, elev, shade) {
   return Ta + Math.max(-4, Math.min(5, adj));
 }
 
-// -- FUTURE FEATURE v2: Pets Profile - Fur Temperature & Heat Stress ----------
-// Dogs and cats experience heat very differently from humans:
-//
-//   FUR SURFACE TEMPERATURE
-//     Dark/thick fur absorbs solar radiation and can run significantly hotter
-//     than air temperature - similar in principle to calcConcreteTemp() but
-//     with fur-specific albedo values:
-//       Black fur:   albedo ~0.05  (almost all radiation absorbed)
-//       Brown fur:   albedo ~0.15
-//       Golden fur:  albedo ~0.25
-//       White fur:   albedo ~0.40
-//     Add a calcFurSurfaceTemp(Ta, globalRad, windSpeed, furAlbedo) function
-//     mirroring calcConcreteTemp but with appropriate convective coefficients
-//     for fur (lower hc than concrete - fur insulates).
-//
-//   PAW BURN RISK
-//     Paw pads are highly sensitive to surface temperature. Use calcConcreteTemp()
-//     output directly - the existing concrete surface temp is already the right
-//     number. Threshold guidance:
-//       < 40 -C  - safe
-//       40-52 -C - discomfort / possible burn (hold-your-hand-for-7-seconds test)
-//       > 52 -C  - burns within 60 seconds
-//     Display as a simple traffic-light column in the Pets profile.
-//
-//   BREED-SPECIFIC HEAT STRESS
-//     Brachycephalic breeds (Bulldogs, Pugs, French Bulldogs, Persians) have
-//     severely impaired thermoregulation - their safe UTCI ceiling is much lower.
-//     A breed selector (Normal / Brachycephalic / Senior) applies a risk multiplier
-//     to the UTCI thresholds, similar to the planned activity modifier.
-//
-//   SUGGESTED COLUMNS FOR PETS PROFILE
-//     Hour | Air Temp | UTCI+P | Fur Surface Temp | Paw Burn Risk | Shade Advised
-//
-// -----------------------------------------------------------------------------
+// -- Pets Profile - Fur Surface Temperature -----------------------------------
+// Cats and small dogs experience solar heat differently from bare pavement:
+// a coat absorbs radiation like calcConcreteTemp()'s slab, but a thin/short
+// coat over a living, blood-perfused body insulates less than a heavy double
+// coat and never bakes as hot as dead concrete. furAlbedo varies by coat
+// colour (FUR_COLORS in utils.js): black ~0.05, brown ~0.15, golden ~0.25,
+// white ~0.40. Paw burn risk reuses calcConcreteTemp() output directly (the
+// ground/pavement surface temp is already the right number for paw contact):
+//   < 40 -C  - safe
+//   40-52 -C - discomfort / possible burn (hold-your-hand-for-7-seconds test)
+//   > 52 -C  - burns within 60 seconds
+// A breed-specific multiplier (brachycephalic/senior) is deliberately not
+// modelled - this profile targets cats and small dogs as the reference animal.
+// -------------------------------------------------------------------------
+export function calcFurSurfaceTemp(Ta, globalRad, windSpeed, solElev, furAlbedo = 0.15) {
+  if (globalRad == null || Ta == null) return null;
+  const elevDeg = (solElev != null) ? Math.max(5, solElev) : 45;
+  const angleCorrection = Math.sin(elevDeg * Math.PI / 180);
+  const absorbed = globalRad * (1 - furAlbedo) * angleCorrection;
+  // Lower convective coefficient than bare concrete (hc=10+4.5*sqrt(v)) -
+  // trapped air in the coat insulates, running the surface hotter for a
+  // given wind speed than pavement, but not as insulated as a thick double
+  // coat, so it sits between "bare skin" and "heavy fur".
+  const hc = 7 + 3.5 * Math.sqrt(Math.max(windSpeed || 0, 0));
+  const Ts = Ta + absorbed / hc;
+  // Floor at air temp; cap below concrete's 85-C ceiling - a thin coat over
+  // a living body doesn't bake as hot as dead pavement. No wet-fur/rain
+  // evaporative term yet (future refinement, mirrors calcConcreteTemp's).
+  return Math.max(Ta, Math.min(Ts, 70));
+}
+
+export const LAG_HOURS_FUR = 0.4; // ~24 min - low thermal mass, animal moves in/out of sun
+
+export function calcFurSurfaceTempPass(TaArr, radArr, vaArr, elevArr, furAlbedo = 0.15) {
+  const n = TaArr.length;
+  const result = new Array(n);
+  const alpha = 1 - Math.exp(-1 / LAG_HOURS_FUR);
+  let Tf = calcFurSurfaceTemp(TaArr[0], radArr[0], vaArr[0], elevArr[0], furAlbedo) ?? TaArr[0];
+  for (let i = 0; i < n; i++) {
+    const target = calcFurSurfaceTemp(TaArr[i], radArr[i], vaArr[i], elevArr[i], furAlbedo) ?? TaArr[i];
+    Tf = Tf + alpha * (target - Tf);
+    result[i] = Math.max(TaArr[i], Tf);
+  }
+  return result;
+}
 
 // -- Vehicle-at-speed thermal model (IMPLEMENTED) ------------------------------
 // calcVehicleInteriorTemp now takes a speedMph argument (Static / 20 / 50 / 70