chore(release): 4.4.7 [skip ci]

## [4.4.7](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.6...v4.4.7) (2025-10-17)

### Bug Fixes

* **complement-race:** add missing useRef import ([d43829a](d43829ad48))

CHANGELOG.md

@@ -1,3 +1,17 @@
+## [4.4.7](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.6...v4.4.7) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** add missing useRef import ([d43829a](https://github.com/antialias/soroban-abacus-flashcards/commit/d43829ad48f7ee879a46879f5e6ac1256db1f564))
+
+## [4.4.6](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.5...v4.4.6) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** restore smooth train movement with client-side game loop ([46a80cb](https://github.com/antialias/soroban-abacus-flashcards/commit/46a80cbcc8ec39224d4edaf540da25611d48fbdd))
+
 ## [4.4.5](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.4...v4.4.5) (2025-10-17)
 
 

apps/web/src/arcade-games/complement-race/Provider.tsx

@@ -11,6 +11,7 @@ import {
   useContext,
   useEffect,
   useMemo,
+  useRef,
   useState,
   type ReactNode,
 } from 'react'
@@ -251,6 +252,11 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
   // Debug logging ref (track last logged values)
   const lastLogRef = useState({ key: '', count: 0 })[0]
 
+  // Client-side smooth movement state
+  const [clientPosition, setClientPosition] = useState(0)
+  const [clientPressure, setClientPressure] = useState(0)
+  const lastUpdateRef = useRef(Date.now())
+
   // Transform multiplayer state to look like single-player state
   const compatibleState = useMemo((): CompatibleGameState => {
     const localPlayer = localPlayerId ? multiplayerState.players[localPlayerId] : null
@@ -316,8 +322,8 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
 
       // Sprint mode specific
       momentum: localPlayer?.momentum || 0,
-      trainPosition: localPlayer?.position || 0,
-      pressure: localPlayer?.pressure || 0, // Use actual pressure from server (has decay)
+      trainPosition: clientPosition, // Use client-calculated smooth position
+      pressure: clientPressure, // Use client-calculated smooth pressure
       elapsedTime: multiplayerState.gameStartTime ? Date.now() - multiplayerState.gameStartTime : 0,
       lastCorrectAnswerTime: localPlayer?.lastAnswerTime || Date.now(),
       currentRoute: multiplayerState.currentRoute,
@@ -339,7 +345,46 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
       adaptiveFeedback: localUIState.adaptiveFeedback,
       difficultyTracker: localUIState.difficultyTracker,
     }
-  }, [multiplayerState, localPlayerId, localUIState])
+  }, [multiplayerState, localPlayerId, localUIState, clientPosition, clientPressure])
+
+  // Client-side game loop for smooth train movement
+  useEffect(() => {
+    if (compatibleState.style !== 'sprint' || !compatibleState.isGameActive) return
+
+    const UPDATE_INTERVAL = 50 // 50ms = ~20fps
+    const SPEED_MULTIPLIER = 0.15 // speed = momentum * 0.15 (% per second)
+
+    const interval = setInterval(() => {
+      const now = Date.now()
+      const deltaTime = now - lastUpdateRef.current
+      lastUpdateRef.current = now
+
+      // Get server momentum (authoritative)
+      const serverMomentum = compatibleState.momentum
+
+      // Calculate speed from momentum
+      const speed = serverMomentum * SPEED_MULTIPLIER
+
+      // Update position continuously based on momentum
+      const positionDelta = (speed * deltaTime) / 1000
+      setClientPosition((prev) => prev + positionDelta)
+
+      // Calculate pressure from momentum (0-150 PSI)
+      const pressure = Math.min(150, (serverMomentum / 100) * 150)
+      setClientPressure(pressure)
+    }, UPDATE_INTERVAL)
+
+    return () => clearInterval(interval)
+  }, [compatibleState.style, compatibleState.isGameActive, compatibleState.momentum])
+
+  // Sync client position with server position on route changes/resets
+  useEffect(() => {
+    const serverPosition = multiplayerState.players[localPlayerId || '']?.position || 0
+    // Only sync if there's a significant jump (route change)
+    if (Math.abs(serverPosition - clientPosition) > 10) {
+      setClientPosition(serverPosition)
+    }
+  }, [multiplayerState.players, localPlayerId, clientPosition])
 
   // Debug logging: only log on answer submission or significant events
   useEffect(() => {

apps/web/src/arcade-games/complement-race/Validator.ts

@@ -169,8 +169,7 @@ export class ComplementRaceValidator
         correctAnswers: 0,
         totalQuestions: 0,
         position: 0,
-        momentum: 50, // Start with some momentum in sprint mode
-        pressure: 60, // Start with initial pressure
+        momentum: 50, // Start with some momentum (position/pressure calculated client-side)
         isReady: false,
         isActive: true,
         currentAnswer: null,
@@ -318,25 +317,15 @@ export class ComplementRaceValidator
         updatedPlayer.position = Math.min(100, player.position + 100 / state.config.raceGoal)
       }
     } else if (state.config.style === 'sprint') {
-      // Sprint: Update momentum, pressure, AND position
+      // Sprint: Update momentum only (position calculated client-side for smooth movement)
       if (correct) {
         updatedPlayer.momentum = Math.min(100, player.momentum + 15)
-        // Add pressure on correct answer (add steam to boiler)
-        updatedPlayer.pressure = Math.min(100, player.pressure + 20)
       } else {
         updatedPlayer.momentum = Math.max(0, player.momentum - 10)
-        // Less pressure added on wrong answer
-        updatedPlayer.pressure = Math.min(100, player.pressure + 5)
       }
 
-      // Pressure decay: Every answer causes some steam to escape
-      // Decay rate: 8 points per answer (pressure naturally decreases over time)
-      updatedPlayer.pressure = Math.max(0, updatedPlayer.pressure - 8)
-
-      // Move train based on momentum (momentum/20 = position change per answer)
-      // Higher momentum = faster movement
-      const moveDistance = updatedPlayer.momentum / 20
-      updatedPlayer.position = Math.min(100, player.position + moveDistance)
+      // Position is calculated client-side continuously based on momentum
+      // This allows for smooth 20fps movement instead of discrete jumps per answer
     } else if (state.config.style === 'survival') {
       // Survival: Always move forward, speed based on accuracy
       const moveDistance = correct ? 5 : 2
@@ -543,7 +532,6 @@ export class ComplementRaceValidator
         ...player,
         position: 0,
         momentum: 50, // Reset momentum to starting value
-        pressure: 60, // Reset pressure to starting value
         passengers: [], // Clear any remaining passengers
       }
     }

apps/web/src/arcade-games/complement-race/types.ts

@@ -62,8 +62,7 @@ export interface PlayerState {
 
   // Position & Progress
   position: number // 0-100% for practice/sprint, lap count for survival
-  momentum: number // 0-100 (sprint mode only)
-  pressure: number // 0-100 (sprint mode only, decays over time)
+  momentum: number // 0-100 (sprint mode only, position/pressure calculated client-side)
 
   // Current state
   isReady: boolean

package.json

@@ -1,6 +1,6 @@
 {
   "name": "soroban-monorepo",
-  "version": "4.4.5",
+  "version": "4.4.7",
   "private": true,
   "description": "Beautiful Soroban Flashcard Generator - Monorepo",
   "workspaces": [