Sync shipping-route weather system

server/main.go

@@ -40,6 +40,13 @@ const (
 	respawnDelay       = 2200 * time.Millisecond
 	simTick            = time.Second / 30
 	snapshotTick       = 50 * time.Millisecond
+	windPatternMS      = 16000.0
+	windMinStrength    = 7.0
+	windMaxStrength    = 24.0
+	routeMinCoreRadius = 220.0
+	routeEdgeDepth     = 320.0
+	stormFrontPeriodMS = 110000.0
+	stormFrontRadius   = 720.0
 )
 
 type config struct {
@@ -149,14 +156,33 @@ type projectileState struct {
 	bornAt  time.Time
 }
 
+type weatherRoute struct {
+	ID    string  `json:"id"`
+	FromX float64 `json:"fromX"`
+	FromY float64 `json:"fromY"`
+	ToX   float64 `json:"toX"`
+	ToY   float64 `json:"toY"`
+	Width float64 `json:"width"`
+}
+
+type weatherWind struct {
+	X              float64
+	Y              float64
+	Strength       float64
+	RouteInfluence float64
+	RouteEdge      float64
+	StormIntensity float64
+}
+
 type clientMessage struct {
-	Type     string  `json:"type"`
+	Type     string         `json:"type"`
-	Seq      int64   `json:"seq"`
+	Seq      int64          `json:"seq"`
-	Throttle float64 `json:"throttle"`
+	Throttle float64        `json:"throttle"`
-	Steer    float64 `json:"steer"`
+	Steer    float64        `json:"steer"`
-	Stop     bool    `json:"stop"`
+	Stop     bool           `json:"stop"`
-	Docked   bool    `json:"docked"`
+	Docked   bool           `json:"docked"`
-	Side     string  `json:"side"`
+	Side     string         `json:"side"`
+	Routes   []weatherRoute `json:"routes,omitempty"`
 }
 
 type serverMessage struct {
@@ -193,6 +219,7 @@ type hub struct {
 	projectiles    map[string]projectileState
 	nextProjectile uint64
 	worldSeed      string
+	weatherRoutes  []weatherRoute
 }
 
 func newHub(seed string, fakePlayers ...int) *hub {
@@ -281,6 +308,152 @@ func (h *hub) count() int {
 	return len(h.clients)
 }
 
+func (h *hub) setWeatherRoutes(routes []weatherRoute) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if len(h.weatherRoutes) > 0 || len(routes) == 0 {
+		return
+	}
+	count := len(routes)
+	if count > 24 {
+		count = 24
+	}
+	h.weatherRoutes = make([]weatherRoute, 0, count)
+	for _, route := range routes[:count] {
+		h.weatherRoutes = append(h.weatherRoutes, weatherRoute{
+			ID:    strings.TrimSpace(route.ID),
+			FromX: clampFloat(route.FromX, 0, worldSize),
+			FromY: clampFloat(route.FromY, 0, worldSize),
+			ToX:   clampFloat(route.ToX, 0, worldSize),
+			ToY:   clampFloat(route.ToY, 0, worldSize),
+			Width: clampFloat(route.Width, 120, 320),
+		})
+	}
+}
+
+func smootherStep01(value float64) float64 {
+	t := clampFloat(value, 0, 1)
+	return t * t * t * (t*(t*6-15) + 10)
+}
+
+func hash01(index float64, salt float64) float64 {
+	value := math.Sin(index*12.9898+salt*78.233) * 43758.5453123
+	return value - math.Floor(value)
+}
+
+func shortestAngleDeltaRad(from, to float64) float64 {
+	delta := math.Mod(to-from, math.Pi*2)
+	if delta > math.Pi {
+		delta -= math.Pi * 2
+	}
+	if delta < -math.Pi {
+		delta += math.Pi * 2
+	}
+	return delta
+}
+
+func windTargetForSlot(slot float64) (float64, float64) {
+	angle := hash01(slot, 1) * math.Pi * 2
+	strength := windMinStrength + hash01(slot, 2)*(windMaxStrength-windMinStrength)
+	return angle, strength
+}
+
+func semiRandomWindPatternAt(timeMs float64) (float64, float64) {
+	if timeMs < 0 {
+		timeMs = 0
+	}
+	slot := math.Floor(timeMs / windPatternMS)
+	phase := math.Mod(timeMs, windPatternMS) / windPatternMS
+	currentAngle, currentStrength := windTargetForSlot(slot)
+	nextAngle, nextStrength := windTargetForSlot(slot + 1)
+	blend := smootherStep01((phase - 0.18) / 0.82)
+	angle := currentAngle + shortestAngleDeltaRad(currentAngle, nextAngle)*blend
+	strength := currentStrength + (nextStrength-currentStrength)*blend
+	gust := math.Sin(timeMs/2300+slot*0.73) * (1.1 + hash01(slot, 3)*1.8)
+	return angle, math.Max(4, strength+gust)
+}
+
+func pointSegmentDistanceXY(x, y float64, route weatherRoute) float64 {
+	abX := route.ToX - route.FromX
+	abY := route.ToY - route.FromY
+	apX := x - route.FromX
+	apY := y - route.FromY
+	lengthSquared := abX*abX + abY*abY
+	if lengthSquared <= 1 {
+		return math.Hypot(apX, apY)
+	}
+	t := clampFloat((apX*abX+apY*abY)/lengthSquared, 0, 1)
+	nearestX := route.FromX + abX*t
+	nearestY := route.FromY + abY*t
+	return math.Hypot(x-nearestX, y-nearestY)
+}
+
+func (h *hub) routeWeatherAtLocked(x, y float64) (float64, float64) {
+	if len(h.weatherRoutes) == 0 {
+		return 0, 0
+	}
+	distance := math.Inf(1)
+	width := 220.0
+	for _, route := range h.weatherRoutes {
+		candidate := pointSegmentDistanceXY(x, y, route)
+		if candidate < distance {
+			distance = candidate
+			width = route.Width
+		}
+	}
+	core := math.Max(routeMinCoreRadius, width*0.9)
+	outer := core + routeEdgeDepth
+	calmStart := core * 0.65
+	influence := 1 - smootherStep01((distance-calmStart)/math.Max(1, outer-calmStart))
+	edgeCenter := core + routeEdgeDepth*0.5
+	edgeHalf := routeEdgeDepth * 0.62
+	edge := smootherStep01(1 - math.Abs(distance-edgeCenter)/edgeHalf)
+	return clampFloat(influence, 0, 1), clampFloat(edge, 0, 1)
+}
+
+func stormFrontIntensityAt(x, y, timeMs float64) float64 {
+	raw := math.Mod(timeMs, stormFrontPeriodMS)
+	if raw < 0 {
+		raw += stormFrontPeriodMS
+	}
+	phase := raw / stormFrontPeriodMS
+	front := func(offset, yBase, yWave, scale float64) float64 {
+		t := math.Mod(phase+offset, 1)
+		centerX := -900 + t*(worldSize+1800)
+		centerY := worldSize * (yBase + math.Sin(t*math.Pi*2+offset*4.7)*yWave)
+		distance := math.Hypot((x-centerX)/1.55, y-centerY)
+		return clampFloat(1-distance/stormFrontRadius, 0, 1) * scale
+	}
+	return math.Max(
+		front(0, 0.35, 0.18, 0.95),
+		front(0.53, 0.72, 0.13, 0.74),
+	)
+}
+
+func (h *hub) weatherWindAtLocked(x, y float64, now time.Time) weatherWind {
+	timeMs := float64(now.UnixMilli())
+	timeSeconds := timeMs / 1000
+	angle, strength := semiRandomWindPatternAt(timeMs)
+	routeInfluence, routeEdge := h.routeWeatherAtLocked(x, y)
+	openExposure := 1 - routeInfluence
+	storm := stormFrontIntensityAt(x, y, timeMs)
+	directionalVariance := 0.022 + openExposure*0.09 + routeEdge*0.055 + storm*0.2
+	localAngle := angle +
+		math.Sin((x+y)/880+timeSeconds/31)*directionalVariance +
+		math.Sin(timeSeconds/5.2+x/1400)*storm*0.12
+	strengthScale := 0.72 + openExposure*0.5 + routeEdge*0.16 + storm*0.68
+	localStrength := strength*strengthScale +
+		math.Sin((x-y)/760+timeSeconds/4.7)*(0.45+openExposure*0.9+storm*1.2)
+	return weatherWind{
+		X:              math.Cos(localAngle) * localStrength,
+		Y:              math.Sin(localAngle) * localStrength,
+		Strength:       math.Abs(localStrength),
+		RouteInfluence: routeInfluence,
+		RouteEdge:      routeEdge,
+		StormIntensity: storm,
+	}
+}
+
 func (h *hub) updateInput(id string, msg clientMessage) {
 	h.mu.Lock()
 	defer h.mu.Unlock()
@@ -322,6 +495,7 @@ func (h *hub) fireLocked(c *client, side string, now time.Time) bool {
 	base := headingRadians(c.state.Angle) + sideSign*math.Pi/2
 	shipVX := math.Cos(headingRadians(c.state.Angle)) * c.state.Speed
 	shipVY := math.Sin(headingRadians(c.state.Angle)) * c.state.Speed
+	shotWind := h.weatherWindAtLocked(c.state.X, c.state.Y, now)
 
 	for _, offset := range []float64{-7, 0, 7} {
 		angle := base + offset*math.Pi/180
@@ -331,8 +505,8 @@ func (h *hub) fireLocked(c *client, side string, now time.Time) bool {
 			ID: projectileID, OwnerID: c.state.ID,
 			X:      c.state.X + math.Cos(base)*28,
 			Y:      c.state.Y + math.Sin(base)*28,
-			VX:     math.Cos(angle)*shotSpeed + shipVX*0.25,
+			VX:     math.Cos(angle)*shotSpeed + shipVX*0.25 + shotWind.X*0.22,
-			VY:     math.Sin(angle)*shotSpeed + shipVY*0.25,
+			VY:     math.Sin(angle)*shotSpeed + shipVY*0.25 + shotWind.Y*0.22,
 			Damage: shotDamage,
 			bornAt: now,
 		}
@@ -345,16 +519,17 @@ func (h *hub) step(now time.Time, dt float64) {
 	defer h.mu.Unlock()
 
 	for _, c := range h.clients {
+		wind := h.weatherWindAtLocked(c.state.X, c.state.Y, now)
 		if c.state.Bot {
 			input, fireSide := h.fakeCaptainDecisionLocked(c, now)
 			c.input = input
-			stepPlayer(&c.state, c.input, now, dt)
+			stepPlayerWithWind(&c.state, c.input, now, dt, wind.X, wind.Y)
 			if fireSide != "" {
 				h.fireLocked(c, fireSide, now)
 			}
 			continue
 		}
-		stepPlayer(&c.state, c.input, now, dt)
+		stepPlayerWithWind(&c.state, c.input, now, dt, wind.X, wind.Y)
 	}
 
 	for id, shot := range h.projectiles {
@@ -482,6 +657,17 @@ func (h *hub) fakeCaptainDecisionLocked(c *client, now time.Time) (inputState, s
 }
 
 func stepPlayer(state *playerState, input inputState, now time.Time, dt float64) {
+	stepPlayerWithWind(state, input, now, dt, 0, 0)
+}
+
+func stepPlayerWithWind(
+	state *playerState,
+	input inputState,
+	now time.Time,
+	dt float64,
+	windX float64,
+	windY float64,
+) {
 	state.InputSeq = input.Seq
 	if !state.Alive {
 		if state.RespawnAt > 0 && now.UnixMilli() >= state.RespawnAt {
@@ -522,8 +708,8 @@ func stepPlayer(state *playerState, input inputState, now time.Time, dt float64)
 	state.Angle = normalizeAngle(state.Angle + playerTurnRate*turnStrength*directionSign*input.Steer*dt)
 
 	heading := headingRadians(state.Angle)
-	state.X = clampFloat(state.X+math.Cos(heading)*state.Speed*dt, 0, worldSize)
+	state.X = clampFloat(state.X+(math.Cos(heading)*state.Speed+windX)*dt, 0, worldSize)
-	state.Y = clampFloat(state.Y+math.Sin(heading)*state.Speed*dt, 0, worldSize)
+	state.Y = clampFloat(state.Y+(math.Sin(heading)*state.Speed+windY)*dt, 0, worldSize)
 }
 
 func headingRadians(angle float64) float64 { return (angle - 90) * math.Pi / 180 }
@@ -854,7 +1040,7 @@ func (a *app) ws(w http.ResponseWriter, r *http.Request) {
 		Type: "welcome", PlayerID: t.Subject, WorldSeed: a.cfg.WorldSeed,
 		ServerTime: time.Now().UnixMilli(),
 	})
-	conn.SetReadLimit(4096)
+	conn.SetReadLimit(8192)
 	for {
 		_ = conn.SetReadDeadline(time.Now().Add(45 * time.Second))
 		var msg clientMessage
@@ -866,6 +1052,8 @@ func (a *app) ws(w http.ResponseWriter, r *http.Request) {
 			a.hub.updateInput(t.Subject, msg)
 		case "fire":
 			a.hub.fire(t.Subject, strings.ToLower(msg.Side), time.Now())
+		case "weather-layout":
+			a.hub.setWeatherRoutes(msg.Routes)
 		}
 	}
 }

server/main_test.go

@@ -226,3 +226,51 @@ func TestFakeCaptainDoesNotAggroHumanAcrossWholeWorld(t *testing.T) {
 		t.Fatalf("bot should patrol when human is far: %+v", input)
 	}
 }
+
+
+func TestShippingRouteWeatherCalmsAuthoritativeWind(t *testing.T) {
+	h := newHub("TEST")
+	h.setWeatherRoutes([]weatherRoute{{
+		ID: "route-1", FromX: 1000, FromY: 1000, ToX: 3600, ToY: 1000, Width: 220,
+	}})
+	now := time.UnixMilli(0)
+	lane := h.weatherWindAtLocked(2200, 1000, now)
+	open := h.weatherWindAtLocked(2200, 2200, now)
+	if lane.RouteInfluence < 0.9 {
+		t.Fatalf("lane influence=%v", lane.RouteInfluence)
+	}
+	if open.RouteInfluence > 0.05 {
+		t.Fatalf("open influence=%v", open.RouteInfluence)
+	}
+	if lane.Strength >= open.Strength {
+		t.Fatalf("lane wind=%v open wind=%v", lane.Strength, open.Strength)
+	}
+}
+
+func TestWeatherLayoutIsSanitizedAndOnlyAcceptedOnce(t *testing.T) {
+	h := newHub("TEST")
+	h.setWeatherRoutes([]weatherRoute{{
+		ID: "route", FromX: -20, FromY: 100, ToX: 9000, ToY: 200, Width: 900,
+	}})
+	if len(h.weatherRoutes) != 1 {
+		t.Fatalf("routes=%d", len(h.weatherRoutes))
+	}
+	route := h.weatherRoutes[0]
+	if route.FromX != 0 || route.ToX != worldSize || route.Width != 320 {
+		t.Fatalf("unsanitized route=%+v", route)
+	}
+	h.setWeatherRoutes([]weatherRoute{{ID: "replacement", FromX: 1, FromY: 1, ToX: 2, ToY: 2, Width: 120}})
+	if h.weatherRoutes[0].ID != "route" {
+		t.Fatal("weather layout should be immutable after first accepted layout")
+	}
+}
+
+func TestAuthoritativeMovementIncludesWeatherDrift(t *testing.T) {
+	state := newPlayerState("weather-player", "Weather", 0, 0)
+	state.X, state.Y = 2000, 2000
+	startX, startY := state.X, state.Y
+	stepPlayerWithWind(&state, inputState{Seq: 1}, time.Unix(100, 0), 1, 12, -7)
+	if state.X == startX || state.Y == startY {
+		t.Fatalf("weather drift not applied: x=%v y=%v", state.X, state.Y)
+	}
+}

src/environment-physics.js

@@ -18,6 +18,10 @@ export const ENVIRONMENT_ISLANDS = [
 const WIND_PATTERN_MS = 16000;
 const WIND_MIN_STRENGTH = 7;
 const WIND_MAX_STRENGTH = 24;
+const ROUTE_MIN_CORE_RADIUS = 220;
+const ROUTE_EDGE_DEPTH = 320;
+const STORM_FRONT_PERIOD_MS = 110000;
+const STORM_FRONT_RADIUS = 720;
 
 const clamp01 = (value) => Math.max(0, Math.min(1, value));
 const smootherStep = (value) => {
@@ -65,20 +69,142 @@ export const semiRandomWindPattern = (timeMs = 0) => {
   };
 };
 
+const pointSegmentDistance = (point, from, to) => {
+  const abX = (to?.x || 0) - (from?.x || 0);
+  const abY = (to?.y || 0) - (from?.y || 0);
+  const apX = (point?.x || 0) - (from?.x || 0);
+  const apY = (point?.y || 0) - (from?.y || 0);
+  const lengthSquared = abX * abX + abY * abY;
+  if (lengthSquared <= 1) return Math.hypot(apX, apY);
+  const t = Math.max(0, Math.min(1, (apX * abX + apY * abY) / lengthSquared));
+  const nearestX = (from?.x || 0) + abX * t;
+  const nearestY = (from?.y || 0) + abY * t;
+  return Math.hypot((point?.x || 0) - nearestX, (point?.y || 0) - nearestY);
+};
+
+export const routeWeatherAt = ({
+  x = 0,
+  y = 0,
+  routes = [],
+} = {}) => {
+  let nearestRoute = null;
+  let routeDistance = Infinity;
+
+  for (const route of routes || []) {
+    const distance = pointSegmentDistance({ x, y }, route?.from, route?.to);
+    if (distance < routeDistance) {
+      nearestRoute = route;
+      routeDistance = distance;
+    }
+  }
+
+  if (!nearestRoute) {
+    return {
+      routeId: null,
+      routeDistance: Infinity,
+      routeInfluence: 0,
+      routeEdge: 0,
+      openExposure: 1,
+      zone: 'open-sky',
+    };
+  }
+
+  const coreRadius = Math.max(
+    ROUTE_MIN_CORE_RADIUS,
+    Math.max(0, Number(nearestRoute.width) || 0) * 0.9,
+  );
+  const outerRadius = coreRadius + ROUTE_EDGE_DEPTH;
+  const calmStart = coreRadius * 0.65;
+  const routeInfluence = 1 - smootherStep(
+    (routeDistance - calmStart) / Math.max(1, outerRadius - calmStart),
+  );
+  const edgeCenter = coreRadius + ROUTE_EDGE_DEPTH * 0.5;
+  const edgeHalfWidth = ROUTE_EDGE_DEPTH * 0.62;
+  const routeEdge = smootherStep(
+    1 - Math.abs(routeDistance - edgeCenter) / edgeHalfWidth,
+  );
+  const openExposure = 1 - routeInfluence;
+
+  return {
+    routeId: nearestRoute.id || null,
+    routeDistance,
+    routeInfluence: clamp01(routeInfluence),
+    routeEdge: clamp01(routeEdge),
+    openExposure: clamp01(openExposure),
+    zone: routeInfluence >= 0.72
+      ? 'shipping-lane'
+      : routeInfluence >= 0.08
+        ? 'route-edge'
+        : 'open-sky',
+  };
+};
+
+export const stormFrontAt = ({
+  x = 0,
+  y = 0,
+  timeMs = 0,
+  worldWidth = 5400,
+  worldHeight = 5400,
+} = {}) => {
+  const period = STORM_FRONT_PERIOD_MS;
+  const raw = ((Number(timeMs) || 0) % period + period) % period;
+  const phase = raw / period;
+
+  const frontIntensity = (offset, yBase, yWave, scale = 1) => {
+    const t = (phase + offset) % 1;
+    const centerX = -900 + t * (worldWidth + 1800);
+    const centerY = worldHeight * (
+      yBase + Math.sin(t * Math.PI * 2 + offset * 4.7) * yWave
+    );
+    const distance = Math.hypot(
+      (x - centerX) / 1.55,
+      y - centerY,
+    );
+    return clamp01(1 - distance / STORM_FRONT_RADIUS) * scale;
+  };
+
+  return Math.max(
+    frontIntensity(0, 0.35, 0.18, 0.95),
+    frontIntensity(0.53, 0.72, 0.13, 0.74),
+  );
+};
+
 export const environmentWindAt = ({
   x = 0,
   y = 0,
   timeMs = 0,
   islands = ENVIRONMENT_ISLANDS,
+  routes = [],
+  worldWidth = 5400,
+  worldHeight = 5400,
 } = {}) => {
   const time = timeMs / 1000;
   const pattern = semiRandomWindPattern(timeMs);
+  const routeWeather = routeWeatherAt({ x, y, routes });
+  const stormIntensity = stormFrontAt({
+    x,
+    y,
+    timeMs,
+    worldWidth,
+    worldHeight,
+  });
 
-  // Small spatial variation prevents the whole map feeling like one rigid conveyor belt.
+  // Shipping lanes damp the broad wind pattern. Their edges are more unstable,
+  // while open sky and moving storm fronts amplify both strength and direction.
+  const directionalVariance = 0.022
+    + routeWeather.openExposure * 0.09
+    + routeWeather.routeEdge * 0.055
+    + stormIntensity * 0.2;
   const localAngle = pattern.angle
-    + Math.sin((x + y) / 880 + time / 31) * 0.055;
+    + Math.sin((x + y) / 880 + time / 31) * directionalVariance
-  const localStrength = pattern.strength
+    + Math.sin(time / 5.2 + x / 1400) * stormIntensity * 0.12;
-    + Math.sin((x - y) / 760 + time / 4.7) * 0.9;
+  const strengthScale = 0.72
+    + routeWeather.openExposure * 0.5
+    + routeWeather.routeEdge * 0.16
+    + stormIntensity * 0.68;
+  const localStrength = pattern.strength * strengthScale
+    + Math.sin((x - y) / 760 + time / 4.7)
+      * (0.45 + routeWeather.openExposure * 0.9 + stormIntensity * 1.2);
 
   let windX = Math.cos(localAngle) * localStrength;
   let windY = Math.sin(localAngle) * localStrength;
@@ -101,11 +227,23 @@ export const environmentWindAt = ({
     windY += normalY * updraft + tangentY * swirl;
   }
 
+  const strength = Math.hypot(windX, windY);
+  const zone = stormIntensity >= 0.55
+    ? 'storm'
+    : routeWeather.zone;
+
   return {
     x: windX,
     y: windY,
-    strength: Math.hypot(windX, windY),
+    strength,
     heading: ((Math.atan2(windY, windX) * 180 / Math.PI) + 450) % 360,
+    routeId: routeWeather.routeId,
+    routeDistance: routeWeather.routeDistance,
+    routeInfluence: routeWeather.routeInfluence,
+    routeEdge: routeWeather.routeEdge,
+    openExposure: routeWeather.openExposure,
+    stormIntensity,
+    zone,
   };
 };
 

src/game-v4.js

@@ -159,6 +159,7 @@ class GameScene extends Phaser.Scene {
     this.multiplayerHasAuthoritativeState = false;
     this.multiplayerDead = false;
     this.multiplayerLastHull = null;
+    this.multiplayerServerClockOffsetMs = 0;
     this.multiplayerSendAccumulatorMs = 0;
 
     airshipLog('scene:init', {
@@ -226,7 +227,12 @@ class GameScene extends Phaser.Scene {
     this.createPlayerSmoke();
 
     this.handleMultiplayerSnapshot = (event) => {
-      this.syncMultiplayerSnapshot(event.detail || {});
+      const detail = event.detail || {};
+      const serverTime = Number(detail.serverTime) || 0;
+      if (serverTime > 0) {
+        this.multiplayerServerClockOffsetMs = serverTime - Date.now();
+      }
+      this.syncMultiplayerSnapshot(detail);
     };
     this.handleMultiplayerState = (event) => {
       if (event.detail?.state === 'online') return;
@@ -242,6 +248,7 @@ class GameScene extends Phaser.Scene {
     };
     window.addEventListener('airship:multiplayer-snapshot', this.handleMultiplayerSnapshot);
     window.addEventListener('airship:multiplayer-state', this.handleMultiplayerState);
+    window.airshipMultiplayer?.setWeatherRoutes?.(this.world.tradeRoutes);
 
     this.pirates = this.physics.add.group();
     this.merchants = this.physics.add.group();
@@ -362,6 +369,25 @@ class GameScene extends Phaser.Scene {
 
 
 
+  weatherTimeMs() {
+    if (window.airshipMultiplayer?.isConnected?.()) {
+      return Date.now() + (this.multiplayerServerClockOffsetMs || 0);
+    }
+    return this.time?.now ?? 0;
+  }
+
+  weatherWindAt(x, y, timeMs = this.weatherTimeMs()) {
+    return environmentWindAt({
+      x,
+      y,
+      timeMs,
+      islands: this.world?.islands,
+      routes: this.world?.tradeRoutes,
+      worldWidth: this.world?.width || WORLD_SIZE,
+      worldHeight: this.world?.height || WORLD_SIZE,
+    });
+  }
+
   createRollingClouds() {
     if (!this.textures.exists('rolling-cloud')) {
       const cloudTexture = this.make.graphics({ x: 0, y: 0, add: false });
@@ -434,15 +460,10 @@ class GameScene extends Phaser.Scene {
     if (!this.rollingClouds?.length) return;
 
     const dt = Math.min(deltaMs / 1000, 0.05);
-    const now = this.time?.now ?? 0;
+    const now = this.weatherTimeMs();
 
     for (const cloud of this.rollingClouds) {
-      const wind = environmentWindAt({
+      const wind = this.weatherWindAt(cloud.x, cloud.y, now);
-        x: cloud.x,
-        y: cloud.y,
-        timeMs: now,
-        islands: this.world?.islands,
-      });
       const driftScale = cloud.getData('driftScale') || 1;
       cloud.x += wind.x * driftScale * dt;
       cloud.y += wind.y * driftScale * dt;
@@ -459,8 +480,17 @@ class GameScene extends Phaser.Scene {
         const weatherPhase = cloud.getData('weatherPhase') || 0;
         const cyclePosition = (now % weatherCycleMs) / weatherCycleMs;
         const weatherWave = 0.5 + 0.5 * Math.sin(cyclePosition * Math.PI * 2 + weatherPhase);
-        const windPresence = clamp((wind.strength - 5) / 18, 0, 1);
+        const windPresence = clamp((wind.strength - 5) / 24, 0, 1);
-        const targetPresence = clamp(weatherWave * 0.72 + windPresence * 0.38 - 0.12, 0, 1);
+        const routeCloudiness = 0.32
+          + (1 - (wind.routeInfluence || 0)) * 0.68
+          + (wind.routeEdge || 0) * 0.3
+          + (wind.stormIntensity || 0) * 0.85;
+        const targetPresence = clamp(
+          (weatherWave * 0.62 + windPresence * 0.32 - 0.1) * routeCloudiness
+            + (wind.stormIntensity || 0) * 0.28,
+          0,
+          1,
+        );
         const previousPresence = cloud.getData('presence') ?? targetPresence;
         presence = Phaser.Math.Linear(previousPresence, targetPresence, Math.min(1, dt * 0.7));
         cloud.setData('presence', presence);
@@ -975,12 +1005,7 @@ class GameScene extends Phaser.Scene {
       const spread = Phaser.Math.FloatBetween(-0.16, 0.16);
       const trailHeading = heading + Math.PI + spread;
       const trailSpeed = Phaser.Math.Linear(16, 46, effectiveForwardThrust) * Phaser.Math.FloatBetween(0.82, 1.16);
-      const localWind = environmentWindAt({
+      const localWind = this.weatherWindAt(sternX, sternY);
-        x: sternX,
-        y: sternY,
-        timeMs: this.time.now,
-        islands: this.world?.islands,
-      });
       const velocityX = Math.cos(trailHeading) * trailSpeed + localWind.x * 1.4;
       const velocityY = Math.sin(trailHeading) * trailSpeed + localWind.y * 1.4;
 
@@ -1190,12 +1215,7 @@ class GameScene extends Phaser.Scene {
       merchant.angle += clamp(delta, -34 * dt, 34 * dt);
 
       const h = headingRad(merchant);
-      const wind = environmentWindAt({
+      const wind = this.weatherWindAt(merchant.x, merchant.y);
-        x: merchant.x,
-        y: merchant.y,
-        timeMs: this.time.now,
-        islands: this.world?.islands,
-      });
       const velocity = velocityWithEnvironment(
         Math.cos(h) * (merchant.getData('speed') || 76),
         Math.sin(h) * (merchant.getData('speed') || 76),
@@ -1780,14 +1800,15 @@ class GameScene extends Phaser.Scene {
       this.player.anims.timeScale = 1;
     }
 
-    this.environmentWind = environmentWindAt({
+    this.environmentWind = this.weatherWindAt(this.player.x, this.player.y);
-      x: this.player.x,
-      y: this.player.y,
-      timeMs: this.time.now,
-      islands: this.world?.islands,
-    });
     const h = headingRad(this.player);
-    this.player.setVelocity(Math.cos(h) * this.playerSpeed, Math.sin(h) * this.playerSpeed);
+    const predictedVelocity = velocityWithEnvironment(
+      Math.cos(h) * this.playerSpeed,
+      Math.sin(h) * this.playerSpeed,
+      this.environmentWind,
+      1,
+    );
+    this.player.setVelocity(predictedVelocity.x, predictedVelocity.y);
 
     if (Phaser.Input.Keyboard.JustDown(this.keys.firePort)) this.playerBroadside(-1);
     if (Phaser.Input.Keyboard.JustDown(this.keys.fireStarboard)) this.playerBroadside(1);
@@ -1836,12 +1857,7 @@ class GameScene extends Phaser.Scene {
     }
 
     const h = headingRad(this.player);
-    this.environmentWind = environmentWindAt({
+    this.environmentWind = this.weatherWindAt(this.player.x, this.player.y);
-      x: this.player.x,
-      y: this.player.y,
-      timeMs: this.time.now,
-      islands: this.world?.islands,
-    });
     const playerVelocity = velocityWithEnvironment(
       Math.cos(h) * this.playerSpeed,
       Math.sin(h) * this.playerSpeed,
@@ -1902,12 +1918,7 @@ class GameScene extends Phaser.Scene {
         baseSpeed,
       });
       const h = headingRad(pirate);
-      const pirateWind = environmentWindAt({
+      const pirateWind = this.weatherWindAt(pirate.x, pirate.y);
-        x: pirate.x,
-        y: pirate.y,
-        timeMs: this.time.now,
-        islands: this.world?.islands,
-      });
       const pirateVelocity = velocityWithEnvironment(
         Math.cos(h) * speed,
         Math.sin(h) * speed,
@@ -1984,12 +1995,7 @@ class GameScene extends Phaser.Scene {
       shot.setData('projectileOwner', actor);
       shot.setData('sourceShip', ship);
       if (actor === 'pirate') shot.setData('playerHitQueued', false);
-      const shotWind = environmentWindAt({
+      const shotWind = this.weatherWindAt(x, y);
-        x,
-        y,
-        timeMs: this.time.now,
-        islands: this.world?.islands,
-      });
       const shotVelocity = velocityWithEnvironment(
         Math.cos(angle) * SHOT_SPEED * velocityScale + ship.body.velocity.x * 0.25,
         Math.sin(angle) * SHOT_SPEED * velocityScale + ship.body.velocity.y * 0.25,
@@ -2334,6 +2340,10 @@ class GameScene extends Phaser.Scene {
         windSpeed: this.environmentWind?.strength || 0,
         windHeading: this.environmentWind?.heading || 0,
         concealment: this.player?.getData?.('cloudConcealment') || 0,
+        weatherZone: this.environmentWind?.zone || 'open-sky',
+        routeInfluence: this.environmentWind?.routeInfluence || 0,
+        routeEdge: this.environmentWind?.routeEdge || 0,
+        stormIntensity: this.environmentWind?.stormIntensity || 0,
       },
       trade: {
         activeMerchants: this.merchants?.countActive?.(true) || 0,

src/multiplayer.js

@@ -22,6 +22,7 @@ let inputSequence = 0;
 let profile = null;
 let selfSnapshot = null;
 let worldSeed = 'SKYWARD-001';
+let weatherRoutes = [];
 let multiplayerEnabled = localStorage.getItem(MULTIPLAYER_ENABLED_KEY) !== 'false';
 
 const statusButton = document.createElement('button');
@@ -148,6 +149,7 @@ const connect = async () => {
     inputSequence = 0;
     setStatus('online');
     emitConnection('online');
+    sendWeatherLayout();
   });
 
   ws.addEventListener('message', (event) => {
@@ -217,6 +219,29 @@ const sendInput = (input = {}) => {
   return inputSequence;
 };
 
+const sendWeatherLayout = () => {
+  if (socket?.readyState !== WebSocket.OPEN || weatherRoutes.length === 0) return false;
+  socket.send(JSON.stringify({
+    type: 'weather-layout',
+    routes: weatherRoutes,
+  }));
+  return true;
+};
+
+const setWeatherRoutes = (routes = []) => {
+  weatherRoutes = (routes || [])
+    .slice(0, 24)
+    .map((route) => ({
+      id: String(route?.id || ''),
+      fromX: Number(route?.from?.x) || 0,
+      fromY: Number(route?.from?.y) || 0,
+      toX: Number(route?.to?.x) || 0,
+      toY: Number(route?.to?.y) || 0,
+      width: Number(route?.width) || 220,
+    }));
+  sendWeatherLayout();
+};
+
 const fire = (side) => {
   if (socket?.readyState !== WebSocket.OPEN) return false;
   const normalized = side === 'port' || side === -1 ? 'port' : 'starboard';
@@ -270,6 +295,7 @@ window.airshipMultiplayer = {
   logout,
   connect,
   setEnabled,
+  setWeatherRoutes,
   getState,
   getSelfId: () => selfId,
   isAuthenticated: () => authenticated,

tests/environment-physics.test.mjs

@@ -4,7 +4,9 @@ import assert from 'node:assert/strict';
 import {
   ENVIRONMENT_ISLANDS,
   environmentWindAt,
+  routeWeatherAt,
   semiRandomWindPattern,
+  stormFrontAt,
   velocityWithEnvironment,
 } from '../src/environment-physics.js';
 
@@ -47,8 +49,8 @@ test('ambient wind changes over time and remains bounded', () => {
   const first = environmentWindAt({ x: 1200, y: 1200, timeMs: 0 });
   const later = environmentWindAt({ x: 1200, y: 1200, timeMs: 24000 });
 
-  assert.ok(first.strength > 3 && first.strength < 30);
+  assert.ok(first.strength > 3 && first.strength < 55);
-  assert.ok(later.strength > 3 && later.strength < 30);
+  assert.ok(later.strength > 3 && later.strength < 55);
   assert.notDeepEqual(
     [Math.round(first.x * 100), Math.round(first.y * 100)],
     [Math.round(later.x * 100), Math.round(later.y * 100)],
@@ -80,3 +82,54 @@ test('environment velocity adds wind according to exposure', () => {
   assert.equal(result.x, 106);
   assert.equal(result.y, -16);
 });
+
+
+test('shipping lanes create calm cores with unstable edges and open sky beyond', () => {
+  const routes = [{
+    id: 'shipping-1',
+    from: { x: 1000, y: 1200 },
+    to: { x: 3600, y: 1200 },
+    width: 220,
+  }];
+  const lane = routeWeatherAt({ x: 2200, y: 1200, routes });
+  const edge = routeWeatherAt({ x: 2200, y: 1500, routes });
+  const open = routeWeatherAt({ x: 2200, y: 2200, routes });
+
+  assert.equal(lane.zone, 'shipping-lane');
+  assert.ok(lane.routeInfluence > 0.9);
+  assert.equal(edge.zone, 'route-edge');
+  assert.ok(edge.routeEdge > lane.routeEdge);
+  assert.equal(open.zone, 'open-sky');
+  assert.ok(open.routeInfluence < 0.05);
+});
+
+test('moving storm fronts can cross the world independent of route corridors', () => {
+  const timeMs = 110000 * 0.25;
+  const intensity = stormFrontAt({
+    x: 900,
+    y: 5400 * 0.53,
+    timeMs,
+    worldWidth: 5400,
+    worldHeight: 5400,
+  });
+  assert.ok(intensity > 0.75);
+});
+
+test('route-aware wind is calmer in a shipping lane than nearby open sky', () => {
+  const routes = [{
+    id: 'shipping-1',
+    from: { x: 1000, y: 1000 },
+    to: { x: 3600, y: 1000 },
+    width: 220,
+  }];
+  const lane = environmentWindAt({
+    x: 2200, y: 1000, timeMs: 0, routes, islands: [],
+  });
+  const open = environmentWindAt({
+    x: 2200, y: 2200, timeMs: 0, routes, islands: [],
+  });
+
+  assert.equal(lane.zone, 'shipping-lane');
+  assert.equal(open.zone, 'open-sky');
+  assert.ok(lane.strength < open.strength);
+});

tests/wiring.test.mjs

@@ -322,10 +322,10 @@ test('environment physics adds wind, soft island collision, turbulence, and proj
   assert.match(source, /this\.physics\.add\.overlap\(this\.player, obstacle, \(\) => \{[\s\S]*?this\.playerSpeed \*= 0\.985;/);
   assert.doesNotMatch(source, /this\.physics\.add\.collider\(this\.pirates, obstacle\)/);
   assert.match(source, /this\.physics\.add\.overlap\(\s*this\.playerShots,[\s\S]*?this\.hitEnvironmentProjectile/);
-  assert.match(source, /this\.environmentWind = environmentWindAt\(\{/);
+  assert.match(source, /this\.environmentWind = this\.weatherWindAt\(this\.player\.x, this\.player\.y\)/);
-  assert.match(source, /const pirateWind = environmentWindAt\(\{/);
+  assert.match(source, /const pirateWind = this\.weatherWindAt\(pirate\.x, pirate\.y\)/);
-  assert.match(source, /const shotWind = environmentWindAt\(\{/);
+  assert.match(source, /const shotWind = this\.weatherWindAt\(x, y\)/);
-  assert.match(source, /const localWind = environmentWindAt\(\{/);
+  assert.match(source, /const localWind = this\.weatherWindAt\(sternX, sternY\)/);
   assert.match(source, /windSpeed: this\.environmentWind\?\.strength/);
 });
 
@@ -351,6 +351,32 @@ test('larger shared world uses smaller player ships and wider fake-captain spaci
   assert.match(server, /distance <= 1100/);
 });
 
+test('shipping-route weather is shared by client visuals and authoritative multiplayer movement', async () => {
+  const [game, environment, multiplayer, server] = await Promise.all([
+    read('src/game-v4.js'),
+    read('src/environment-physics.js'),
+    read('src/multiplayer.js'),
+    read('server/main.go'),
+  ]);
+
+  assert.match(environment, /routeWeatherAt/);
+  assert.match(environment, /stormFrontAt/);
+  assert.match(environment, /\? 'shipping-lane'/);
+  assert.match(environment, /\? 'route-edge'/);
+  assert.match(game, /routes: this\.world\?\.tradeRoutes/);
+  assert.match(game, /routeCloudiness/);
+  assert.match(game, /multiplayerServerClockOffsetMs/);
+  assert.match(game, /setWeatherRoutes\?\.\(this\.world\.tradeRoutes\)/);
+  assert.match(game, /weatherZone: this\.environmentWind\?\.zone/);
+  assert.match(multiplayer, /type: 'weather-layout'/);
+  assert.match(multiplayer, /setWeatherRoutes/);
+  assert.match(server, /type weatherRoute struct/);
+  assert.match(server, /func \(h \*hub\) setWeatherRoutes/);
+  assert.match(server, /func \(h \*hub\) weatherWindAtLocked/);
+  assert.match(server, /stepPlayerWithWind/);
+  assert.match(server, /case "weather-layout":/);
+});
+
 test('authoritative multiplayer server seeds fake captains that move and fight like players', async () => {
   const server = await read('server/main.go');
 
@@ -393,7 +419,7 @@ test('multiplayer transport uses Keycloak tickets with server-authoritative move
   assert.match(server, /func \(h \*hub\) updateInput/);
   assert.match(server, /func \(h \*hub\) fire/);
   assert.match(server, /func \(h \*hub\) step/);
-  assert.match(server, /stepPlayer\(&c\.state, c\.input/);
+  assert.match(server, /stepPlayerWithWind\(&c\.state, c\.input/);
   assert.match(server, /target\.state\.Hull = clampInt/);
   assert.match(server, /target\.state\.RespawnAt/);
   assert.match(server, /time\.NewTicker\(simTick\)/);
@@ -561,8 +587,9 @@ test('rolling clouds include large dense banks that phase in and out with the wi
   assert.match(source, /Phaser\.Math\.FloatBetween\(DENSE_CLOUD_MIN_SCALE, DENSE_CLOUD_MAX_SCALE\)/);
   assert.match(source, /cloud\.setData\(\s*'concealmentRadius',[\s\S]*?DENSE_CLOUD_CONCEALMENT_RADIUS_SCALE/);
   assert.match(source, /cloud\.setData\('weatherCycleMs', Phaser\.Math\.Between\(18000, 36000\)\)/);
-  assert.match(source, /const windPresence = clamp\(\(wind\.strength - 5\) \/ 18, 0, 1\)/);
+  assert.match(source, /const windPresence = clamp\(\(wind\.strength - 5\) \/ 24, 0, 1\)/);
-  assert.match(source, /const targetPresence = clamp\(weatherWave \* 0\.72 \+ windPresence \* 0\.38 - 0\.12, 0, 1\)/);
+  assert.match(source, /const routeCloudiness = 0\.32/);
+  assert.match(source, /\(weatherWave \* 0\.62 \+ windPresence \* 0\.32 - 0\.1\) \* routeCloudiness/);
   assert.match(source, /cloud\.setAlpha\(Phaser\.Math\.Linear\(alphaMin, alphaMax, visibility\) \* presence\)/);
   assert.match(source, /this\.reseedDenseCloudUpwind\(cloud, wind\)/);
   assert.match(source, /cloud\.x = centerX - windX \* \(WORLD_SIZE \/ 2 \+ margin\)/);