calculate player with best average count lag (#147)

* only consider player leader if they lead the entire time

* more

Author: loganmc10

internal/gameServer/server.go

@@ -107,6 +107,20 @@ func (g *GameServer) averageBufferHealth(playerNumber int) (float32, error) {
 	}
 }
 
+func (g *GameServer) averageCountLag(playerNumber int) (float32, error) {
+	defer func() { g.gameData.countLag[playerNumber] = g.gameData.countLag[playerNumber][:0] }()
+
+	if len(g.gameData.countLag[playerNumber]) > 0 {
+		var total float32
+		for _, value := range g.gameData.countLag[playerNumber] {
+			total += float32(value)
+		}
+		return total / float32(len(g.gameData.countLag[playerNumber])), nil
+	} else {
+		return 0, fmt.Errorf("no count lag data for player %d", playerNumber)
+	}
+}
+
 func (g *GameServer) ManageBuffer() {
 	for {
 		if !g.Running {
@@ -115,14 +129,18 @@ func (g *GameServer) ManageBuffer() {
 		}
 
 		var bufferHealth float32 = -1.0
+		var countLag float32 = 255
 		var leadPlayer int
 		g.gameDataMutex.Lock() // BufferHealth can be modified by processUDP in a different thread
 		for i := range 4 {
-			var err error
-			g.gameData.averageBufferHealth[i], err = g.averageBufferHealth(i)
-			if err == nil && g.gameData.countLag[i] == 0 {
+			var errBufferHeatlh error
+			var errCountLag error
+			g.gameData.averageBufferHealth[i], errBufferHeatlh = g.averageBufferHealth(i)
+			g.gameData.averageCountLag[i], errCountLag = g.averageCountLag(i)
+			if errBufferHeatlh == nil && errCountLag == nil {
+				// if leadPlayer == 0 {
 				// if g.gameData.averageBufferHealth[i] > bufferHealth {
-				if leadPlayer == 0 {
+				if g.gameData.averageCountLag[i] < countLag {
 					bufferHealth = g.gameData.averageBufferHealth[i]
 					leadPlayer = i + 1
 				}
@@ -155,7 +173,7 @@ func (g *GameServer) ManagePlayers() {
 			_, ok := g.registrations[i]
 			if ok {
 				if g.gameData.playerAlive[i] {
-					g.Logger.Info("player status", "player", i, "regID", g.registrations[i].regID, "bufferHealth", g.gameData.averageBufferHealth[i], "bufferSize", g.gameData.bufferSize, "countLag", g.gameData.countLag[i], "address", g.gameData.playerAddresses[i])
+					g.Logger.Info("player status", "player", i, "regID", g.registrations[i].regID, "bufferHealth", g.gameData.averageBufferHealth[i], "bufferSize", g.gameData.bufferSize, "countLag", g.gameData.averageCountLag[i], "address", g.gameData.playerAddresses[i])
 					playersActive = true
 				} else {
 					g.Logger.Info("player disconnected UDP", "player", i, "regID", g.registrations[i].regID, "address", g.gameData.playerAddresses[i])

internal/gameServer/udp.go

@@ -23,10 +23,11 @@ type GameData struct {
 	playerAddresses     [4]*net.UDPAddr
 	bufferSize          uint32
 	averageBufferHealth [4]float32
+	averageCountLag     [4]float32
 	bufferHealth        [4][]byte
 	inputs              [4]*lru.Cache[uint32, InputData]
 	pendingInput        [4]InputData
-	countLag            [4]uint32
+	countLag            [4][]uint32
 	sendBuffer          []byte
 	recvBuffer          []byte
 	playerAlive         [4]bool
@@ -149,8 +150,8 @@ func (g *GameServer) processUDP(addr *net.UDPAddr) {
 			g.Logger.Error(err, "could not process request", "regID", regID)
 			return
 		}
-		g.gameData.countLag[sendingPlayerNumber] = g.sendUDPInput(count, addr, playerNumber, spectator != 0, sendingPlayerNumber)
-		g.gameDataMutex.Lock() // PlayerAlive and BufferHealth can be modified in different threads
+		g.gameDataMutex.Lock() // playerAlive, countLag and bufferHealth can be modified in different threads
+		g.gameData.countLag[sendingPlayerNumber] = append(g.gameData.countLag[sendingPlayerNumber], g.sendUDPInput(count, addr, playerNumber, spectator != 0, sendingPlayerNumber))
 		g.gameData.bufferHealth[sendingPlayerNumber] = append(g.gameData.bufferHealth[sendingPlayerNumber], g.gameData.recvBuffer[11])
 		g.gameData.playerAlive[sendingPlayerNumber] = true
 		g.gameDataMutex.Unlock()
@@ -214,6 +215,7 @@ func (g *GameServer) createUDPServer() error {
 	for i := range 4 {
 		g.gameData.inputs[i], _ = lru.New[uint32, InputData](InputDataMax)
 		g.gameData.bufferHealth[i] = make([]byte, 0, InputDataMax)
+		g.gameData.countLag[i] = make([]uint32, 0, InputDataMax)
 	}
 	g.gameData.syncValues, _ = lru.New[uint32, []byte](100) // Store up to 100 sync values
 	g.gameData.sendBuffer = make([]byte, 508)