Added systems and msgs for movement component

cardinal/component/movement.go

@@ -13,13 +13,13 @@ var Directions = map[int]Direction{
 }
 
 type Location struct {
-	X float32
-	Y float32
+	X float64
+	Y float64
 }
 
 type Movement struct {
 	CurrentDirection Direction
-	Velocity         float32
+	Velocity         float64
 	CurrentLocation  Location
 }
 

cardinal/main.go

@@ -40,13 +40,15 @@ func MustInitWorld(w *cardinal.World) {
 	Must(
 		cardinal.RegisterComponent[component.Player](w),
 		cardinal.RegisterComponent[component.Health](w),
+		cardinal.RegisterComponent[component.Movement](w),
 	)
 
 	// Register messages (user action)
 	// NOTE: You must register your transactions here for it to be executed.
 	Must(
 		cardinal.RegisterMessage[msg.CreatePlayerMsg, msg.CreatePlayerResult](w, "create-player"),
 		cardinal.RegisterMessage[msg.AttackPlayerMsg, msg.AttackPlayerMsgReply](w, "attack-player"),
+		cardinal.RegisterMessage[msg.MovementPlayerMsg, msg.MovementPlayerMsgReply](w, "movement-player"),
 	)
 
 	// Register queries
@@ -63,6 +65,8 @@ func MustInitWorld(w *cardinal.World) {
 		system.AttackSystem,
 		system.RegenSystem,
 		system.PlayerSpawnerSystem,
+		system.MovementValidationSystem,
+		system.MovementSystem,
 	))
 
 	Must(cardinal.RegisterInitSystems(w,

cardinal/msg/movement_player.go

@@ -1 +1,15 @@
 package msg
+
+type MovementPlayerMsg struct {
+	TargetNickname string  `json:"target"`
+	Velocity       int     `json:"velocity"`
+	Direction      int     `json:"direction"`
+	LocationX      float64 `json:"locationX"`
+	LocationY      float64 `json:"locationY"`
+}
+
+type MovementPlayerMsgReply struct {
+	LocationX float64 `json:"locationX"`
+	LocationY float64 `json:"locationY"`
+	IsValid   bool    `json:"isValid"`
+}

cardinal/system/movement_system.go

@@ -2,6 +2,7 @@
 
 import (
 	"fmt"
+	"math"
 	"pkg.world.dev/world-engine/cardinal"
 	"pkg.world.dev/world-engine/cardinal/search/filter"
 	"pkg.world.dev/world-engine/cardinal/types"
@@ -20,8 +21,8 @@
 			}
 
 			// TODO: How to get delta time?
-			movement.CurrentLocation.X += movement.Velocity * float32(movement.CurrentDirection.X)
-			movement.CurrentLocation.Y += movement.Velocity * float32(movement.CurrentDirection.Y)
+			movement.CurrentLocation.X += movement.Velocity * float64(movement.CurrentDirection.X)
+			movement.CurrentLocation.Y += movement.Velocity * float64(movement.CurrentDirection.Y)
 
 			if err := cardinal.SetComponent[comp.Movement](world, id, movement); err != nil {
 				return true
@@ -31,19 +32,24 @@
 }
 
 func MovementValidationSystem(world cardinal.WorldContext) error {
-	return cardinal.EachMessage[msg.AttackPlayerMsg, msg.AttackPlayerMsgReply](
+	return cardinal.EachMessage[msg.MovementPlayerMsg, msg.MovementPlayerMsgReply](
 		world,
-		func(attack cardinal.TxData[msg.AttackPlayerMsg]) (msg.AttackPlayerMsgReply, error) {
-			playerID, playerHealth, err := queryTargetPlayer(world, attack.Msg.TargetNickname)
+		func(movement cardinal.TxData[msg.MovementPlayerMsg]) (msg.MovementPlayerMsgReply, error) {
+			playerID, playerMovementData, err := queryTargetPlayerMovementData(world, movement.Msg.TargetNickname)
 			if err != nil {
-				return msg.AttackPlayerMsgReply{}, fmt.Errorf("failed to inflict damage: %w", err)
+				return msg.MovementPlayerMsgReply{}, fmt.Errorf("failed to update movement: %w", err)
 			}
-
-			playerHealth.HP -= AttackDamage
-			if err := cardinal.SetComponent[comp.Health](world, playerID, playerHealth); err != nil {
-				return msg.AttackPlayerMsgReply{}, fmt.Errorf("failed to inflict damage: %w", err)
+			const errorTolerance float64 = 0.001
+			if math.Abs(playerMovementData.CurrentLocation.X-movement.Msg.LocationX) > errorTolerance ||
+				math.Abs(playerMovementData.CurrentLocation.Y-movement.Msg.LocationY) > errorTolerance {
+				return msg.MovementPlayerMsgReply{IsValid: false, LocationX: playerMovementData.CurrentLocation.X, LocationY: playerMovementData.CurrentLocation.Y}, nil
+			} else {
+				playerMovementData.CurrentLocation.X = movement.Msg.LocationX
+				playerMovementData.CurrentLocation.Y = movement.Msg.LocationY
+				if err := cardinal.SetComponent[comp.Movement](world, playerID, playerMovementData); err != nil {
+					return msg.MovementPlayerMsgReply{IsValid: false, LocationX: playerMovementData.CurrentLocation.X, LocationY: playerMovementData.CurrentLocation.Y}, fmt.Errorf("failed to update movement: %w", err)
+				}
+				return msg.MovementPlayerMsgReply{IsValid: true, LocationX: playerMovementData.CurrentLocation.X, LocationY: playerMovementData.CurrentLocation.Y}, nil
 			}
-
-			return msg.AttackPlayerMsgReply{Damage: AttackDamage}, nil
 		})
 }

cardinal/system/player_spawner.go

@@ -13,6 +13,13 @@ const (
 	InitialHP = 100
 )
 
+const (
+	InitialXLocation = 0
+	InitialYLocation = 0
+	InitialVelocity  = 0
+	InitialDirection = 0
+)
+
 // PlayerSpawnerSystem spawns players based on `CreatePlayer` transactions.
 // This provides an example of a system that creates a new entity.
 func PlayerSpawnerSystem(world cardinal.WorldContext) error {
@@ -22,6 +29,14 @@ func PlayerSpawnerSystem(world cardinal.WorldContext) error {
 			id, err := cardinal.Create(world,
 				comp.Player{Nickname: create.Msg.Nickname},
 				comp.Health{HP: InitialHP},
+				comp.Movement{
+					CurrentLocation: comp.Location{X: InitialXLocation, Y: InitialYLocation},
+					Velocity:        InitialVelocity,
+					CurrentDirection: comp.Direction{
+						comp.Directions[InitialDirection].X,
+						comp.Directions[InitialDirection].Y,
+					},
+				},
 			)
 			if err != nil {
 				return msg.CreatePlayerResult{}, fmt.Errorf("error creating player: %w", err)

cardinal/system/utils.go

@@ -11,7 +11,7 @@
 )
 
 // queryTargetPlayer queries for the target player's entity ID and health component.
 func queryTargetPlayer(world cardinal.WorldContext, targetNickname string) (types.EntityID, *comp.Health, error) {
 	var playerID types.EntityID
 	var playerHealth *comp.Health
 	var err error
@@ -49,3 +49,42 @@
 
 	return playerID, playerHealth, err
 }
+
+func queryTargetPlayerMovementData(world cardinal.WorldContext, targetNickname string) (types.EntityID, *comp.Movement, error) {
+	var playerID types.EntityID
+	var playerMovementComponent *comp.Movement
+	var err error
+	searchErr := cardinal.NewSearch().Entity(
+		filter.Exact(filter.Component[comp.Player](), filter.Component[comp.Movement]())).Each(world,
+		func(id types.EntityID) bool {
+			var player *comp.Player
+			player, err = cardinal.GetComponent[comp.Player](world, id)
+			if err != nil {
+				return false
+			}
+
+			// Terminates the search if the player is found
+			if player.Nickname == targetNickname {
+				playerID = id
+				playerMovementComponent, err = cardinal.GetComponent[comp.Movement](world, id)
+				if err != nil {
+					return false
+				}
+				return false
+			}
+
+			// Continue searching if the player is not the target player
+			return true
+		})
+	if searchErr != nil {
+		return 0, nil, err
+	}
+	if err != nil {
+		return 0, nil, err
+	}
+	if playerMovementComponent == nil {
+		return 0, nil, fmt.Errorf("player %q does not exist", targetNickname)
+	}
+
+	return playerID, playerMovementComponent, err
+}