reposition tanks on map switch, rework map logic

tanks-backend/TanksServer/Endpoints.cs

@@ -11,7 +11,8 @@ internal sealed class Endpoints(
     ClientScreenServer clientScreenServer,
     PlayerServer playerService,
     ControlsServer controlsServer,
-    MapService mapService
+    MapService mapService,
+    ChangeToRequestedMap changeToRequestedMap
 )
 {
     public void Map(WebApplication app)
@@ -29,8 +30,9 @@ internal sealed class Endpoints(
     {
         if (string.IsNullOrWhiteSpace(name))
             return TypedResults.BadRequest("invalid map name");
-        if (!mapService.TrySwitchTo(name))
+        if (!mapService.TryGetMapByName(name, out var map))
             return TypedResults.NotFound("map with name not found");
+        changeToRequestedMap.Request(map);
         return TypedResults.Ok();
     }
 

tanks-backend/TanksServer/GameLogic/ChangeToRequestedMap.cs

@@ -0,0 +1,24 @@
+namespace TanksServer.GameLogic;
+
+internal sealed class ChangeToRequestedMap(
+    MapService mapService,
+    MapEntityManager entityManager,
+    EmptyTileFinder emptyTileFinder
+) : ITickStep
+{
+    private MapPrototype? _requestedMap;
+
+    public ValueTask TickAsync(TimeSpan delta)
+    {
+        var changeTo = Interlocked.Exchange(ref _requestedMap, null);
+        if (changeTo == null)
+            return ValueTask.CompletedTask;
+
+        mapService.SwitchTo(changeTo);
+        foreach (var t in entityManager.Tanks)
+            t.Position = emptyTileFinder.ChooseEmptyTile().GetCenter().ToFloatPosition();
+        return ValueTask.CompletedTask;
+    }
+
+    public void Request(MapPrototype map) => _requestedMap = map;
+}

tanks-backend/TanksServer/GameLogic/EmptyTileFinder.cs

@@ -0,0 +1,32 @@
+namespace TanksServer.GameLogic;
+
+internal sealed class EmptyTileFinder(
+    MapEntityManager entityManager,
+    MapService mapService
+)
+{
+    public TilePosition ChooseEmptyTile()
+    {
+        var maxMinDistance = 0d;
+        TilePosition spawnTile = default;
+        for (ushort x = 1; x < MapService.TilesPerRow - 1; x++)
+        for (ushort y = 1; y < MapService.TilesPerColumn - 1; y++)
+        {
+            var tile = new TilePosition(x, y);
+            if (mapService.Current.IsWall(tile))
+                continue;
+
+            var tilePixelCenter = tile.GetCenter().ToFloatPosition();
+            var minDistance = entityManager.AllEntities
+                .Select(entity => entity.Position.Distance(tilePixelCenter))
+                .Aggregate(double.MaxValue, Math.Min);
+            if (minDistance <= maxMinDistance)
+                continue;
+
+            maxMinDistance = minDistance;
+            spawnTile = tile;
+        }
+
+        return spawnTile;
+    }
+}

tanks-backend/TanksServer/GameLogic/Map.cs

@@ -0,0 +1,32 @@
+namespace TanksServer.GameLogic;
+
+internal sealed class Map(string name, bool[,] walls)
+{
+    public string Name => name;
+
+    public bool IsWall(int x, int y) => walls[x, y];
+
+    public bool IsWall(PixelPosition position) => walls[position.X, position.Y];
+
+    public bool IsWall(TilePosition position)
+    {
+        var pixel = position.ToPixelPosition();
+
+        for (short dx = 0; dx < MapService.TileSize; dx++)
+        for (short dy = 0; dy < MapService.TileSize; dy++)
+        {
+            if (IsWall(pixel.GetPixelRelative(dx, dy)))
+                return true;
+        }
+
+        return false;
+    }
+
+    public bool TryDestroyWallAt(PixelPosition pixel)
+    {
+        var result = walls[pixel.X, pixel.Y];
+        if (result)
+            walls[pixel.X, pixel.Y] = false;
+        return result;
+    }
+}

tanks-backend/TanksServer/GameLogic/MapEntityManager.cs

@@ -2,7 +2,6 @@ namespace TanksServer.GameLogic;
 
 internal sealed class MapEntityManager(
     ILogger<MapEntityManager> logger,
-    MapService map,
     IOptions<GameRules> options
 )
 {
@@ -34,12 +33,12 @@ internal sealed class MapEntityManager(
 
     public void RemoveWhere(Predicate<Bullet> predicate) => _bullets.RemoveWhere(predicate);
 
-    public void SpawnTank(Player player)
+    public void SpawnTank(Player player, FloatPosition position)
     {
         var tank = new Tank
         {
             Owner = player,
-            Position = ChooseSpawnPosition(),
+            Position = position,
             Rotation = Random.Shared.NextDouble(),
             Magazine = new Magazine(MagazineType.Basic, 0, _rules.MagazineSize)
         };
@@ -47,12 +46,16 @@ internal sealed class MapEntityManager(
         logger.LogInformation("Tank added for player {}", player.Name);
     }
 
-    public void SpawnPowerUp(PowerUpType type, MagazineType? magazineType) => _powerUps.Add(new PowerUp
+    public void SpawnPowerUp(FloatPosition position, PowerUpType type, MagazineType? magazineType)
     {
-        Position = ChooseSpawnPosition(),
-        Type = type,
-        MagazineType = magazineType
-    });
+        var powerUp = new PowerUp
+        {
+            Position = position,
+            Type = type,
+            MagazineType = magazineType
+        };
+        _powerUps.Add(powerUp);
+    }
 
     public void RemoveWhere(Predicate<PowerUp> predicate) => _powerUps.RemoveWhere(predicate);
 
@@ -64,33 +67,8 @@ internal sealed class MapEntityManager(
 
     public Tank? GetCurrentTankOfPlayer(Player player) => _playerTanks.GetValueOrDefault(player);
 
-    private IEnumerable<IMapEntity> AllEntities => Bullets
+    public IEnumerable<IMapEntity> AllEntities => Bullets
         .Cast<IMapEntity>()
         .Concat(Tanks)
         .Concat(PowerUps);
-
-    private FloatPosition ChooseSpawnPosition()
-    {
-        var maxMinDistance = 0d;
-        TilePosition spawnTile = default;
-        for (ushort x = 1; x < MapService.TilesPerRow - 1; x++)
-        for (ushort y = 1; y < MapService.TilesPerColumn - 1; y++)
-        {
-            var tile = new TilePosition(x, y);
-            if (map.Current.IsWall(tile))
-                continue;
-
-            var tilePixelCenter = tile.ToPixelPosition().GetPixelRelative(4, 4).ToFloatPosition();
-            var minDistance = AllEntities
-                .Select(entity => entity.Position.Distance(tilePixelCenter))
-                .Aggregate(double.MaxValue, Math.Min);
-            if (minDistance <= maxMinDistance)
-                continue;
-
-            maxMinDistance = minDistance;
-            spawnTile = tile;
-        }
-
-        return spawnTile.ToPixelPosition().GetPixelRelative(4, 4).ToFloatPosition();
-    }
 }

tanks-backend/TanksServer/GameLogic/MapService.cs

@@ -1,9 +1,14 @@
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
-using SixLabors.ImageSharp;
-using SixLabors.ImageSharp.PixelFormats;
+using TanksServer.Graphics;
 
 namespace TanksServer.GameLogic;
 
+internal abstract class MapPrototype
+{
+    public abstract Map CreateInstance();
+}
+
 internal sealed class MapService
 {
     public const ushort TilesPerRow = 44;
@@ -12,7 +17,7 @@ internal sealed class MapService
     public const ushort PixelsPerRow = TilesPerRow * TileSize;
     public const ushort PixelsPerColumn = TilesPerColumn * TileSize;
 
-    private readonly Dictionary<string, bool[,]> _maps = new();
+    private readonly Dictionary<string, MapPrototype> _maps = new();
 
     public IEnumerable<string> MapNames => _maps.Keys;
 
@@ -27,88 +32,26 @@ internal sealed class MapService
 
         var chosenMapIndex = Random.Shared.Next(_maps.Count);
         var chosenMapName = _maps.Keys.Skip(chosenMapIndex).First();
-        Current = new Map(chosenMapName, _maps[chosenMapName]);
+        Current = _maps[chosenMapName].CreateInstance();
     }
 
+    public bool TryGetMapByName(string name, [MaybeNullWhen(false)] out MapPrototype map)
+        => _maps.TryGetValue(name, out map);
+
+    public void SwitchTo(MapPrototype prototype) => Current = prototype.CreateInstance();
+
     private void LoadMapPng(string file)
     {
-        using var image = Image.Load<Rgba32>(file);
-
-        if (image.Width != PixelsPerRow || image.Height != PixelsPerColumn)
-            throw new FileLoadException($"invalid image size in file {file}");
-
-        var whitePixel = new Rgba32(byte.MaxValue, byte.MaxValue, byte.MaxValue, byte.MaxValue);
-        var walls = new bool[PixelsPerRow, PixelsPerColumn];
-
-        for (var y = 0; y < image.Height; y++)
-        for (var x = 0; x < image.Width; x++)
-            walls[x, y] = image[x, y] == whitePixel;
-
-        _maps.Add(Path.GetFileName(file), walls);
+        var name = Path.GetFileName(file);
+        var prototype = new SpriteMapPrototype(name, Sprite.FromImageFile(file));
+        _maps.Add(Path.GetFileName(file), prototype);
     }
 
     private void LoadMapString(string file)
     {
         var map = File.ReadAllText(file).ReplaceLineEndings(string.Empty).Trim();
-        if (map.Length != TilesPerColumn * TilesPerRow)
-            throw new FileLoadException($"cannot load map {file}: invalid length");
-
-        var walls = new bool[PixelsPerRow, PixelsPerColumn];
-
-        for (ushort tileX = 0; tileX < TilesPerRow; tileX++)
-        for (ushort tileY = 0; tileY < TilesPerColumn; tileY++)
-        {
-            var tile = new TilePosition(tileX, tileY);
-            if (map[tileX + tileY * TilesPerRow] != '#')
-                continue;
-
-            for (byte pixelInTileX = 0; pixelInTileX < TileSize; pixelInTileX++)
-            for (byte pixelInTileY = 0; pixelInTileY < TileSize; pixelInTileY++)
-            {
-                var (x, y) = tile.ToPixelPosition().GetPixelRelative(pixelInTileX, pixelInTileY);
-                walls[x, y] = true;
-            }
-        }
-
-        _maps.Add(Path.GetFileName(file), walls);
-    }
-
-    public bool TrySwitchTo(string name)
-    {
-        if (!_maps.TryGetValue(name, out var mapData))
-            return false;
-        Current = new Map(name, (bool[,]) mapData.Clone());
-        return true;
-    }
-}
-
-internal sealed class Map(string name, bool[,] walls)
-{
-    public string Name => name;
-
-    public bool IsWall(int x, int y) => walls[x, y];
-
-    public bool IsWall(PixelPosition position) => walls[position.X, position.Y];
-
-    public bool IsWall(TilePosition position)
-    {
-        var pixel = position.ToPixelPosition();
-
-        for (short dx = 0; dx < MapService.TileSize; dx++)
-        for (short dy = 0; dy < MapService.TileSize; dy++)
-        {
-            if (IsWall(pixel.GetPixelRelative(dx, dy)))
-                return true;
-        }
-
-        return false;
-    }
-
-    public bool TryDestroyWallAt(PixelPosition pixel)
-    {
-        var result = walls[pixel.X, pixel.Y];
-        if (result)
-            walls[pixel.X, pixel.Y] = false;
-        return result;
+        var name = Path.GetFileName(file);
+        var prototype = new TextMapPrototype(name, map);
+        _maps.Add(name, prototype);
     }
 }

tanks-backend/TanksServer/GameLogic/SpawnPowerUp.cs

@@ -4,7 +4,8 @@ namespace TanksServer.GameLogic;
 
 internal sealed class SpawnPowerUp(
     IOptions<GameRules> options,
-    MapEntityManager entityManager
+    MapEntityManager entityManager,
+    EmptyTileFinder emptyTileFinder
 ) : ITickStep
 {
     private readonly double _spawnChance = options.Value.PowerUpSpawnChance;
@@ -34,7 +35,8 @@ internal sealed class SpawnPowerUp(
             _ => null
         };
 
-        entityManager.SpawnPowerUp(type, magazineType);
+        var position = emptyTileFinder.ChooseEmptyTile().GetCenter().ToFloatPosition();
+        entityManager.SpawnPowerUp(position, type, magazineType);
         return ValueTask.CompletedTask;
     }
 }

tanks-backend/TanksServer/GameLogic/SpriteMapPrototype.cs

@@ -0,0 +1,21 @@
+using System.IO;
+using TanksServer.Graphics;
+
+namespace TanksServer.GameLogic;
+
+internal sealed class SpriteMapPrototype : MapPrototype
+{
+    private readonly string _name;
+    private readonly Sprite _sprite;
+
+    public SpriteMapPrototype(string name, Sprite sprite)
+    {
+        if (sprite.Width != MapService.PixelsPerRow || sprite.Height != MapService.PixelsPerColumn)
+            throw new FileLoadException($"invalid image size in file {_name}");
+
+        _name = name;
+        _sprite = sprite;
+    }
+
+    public override Map CreateInstance() => new(_name, _sprite.ToBoolArray());
+}

tanks-backend/TanksServer/GameLogic/TankSpawnQueue.cs

@@ -4,7 +4,8 @@ namespace TanksServer.GameLogic;
 
 internal sealed class TankSpawnQueue(
     IOptions<GameRules> options,
-    MapEntityManager entityManager
+    MapEntityManager entityManager,
+    EmptyTileFinder tileFinder
 ) : ITickStep
 {
     private readonly ConcurrentQueue<Player> _queue = new();
@@ -25,7 +26,8 @@ internal sealed class TankSpawnQueue(
         if (!TryDequeueNext(out var player))
             return ValueTask.CompletedTask;
 
-        entityManager.SpawnTank(player);
+        var position = tileFinder.ChooseEmptyTile().GetCenter().ToFloatPosition();
+        entityManager.SpawnTank(player, position);
         return ValueTask.CompletedTask;
     }
 

tanks-backend/TanksServer/GameLogic/TextMapPrototype.cs

@@ -0,0 +1,37 @@
+namespace TanksServer.GameLogic;
+
+internal sealed class TextMapPrototype : MapPrototype
+{
+    private readonly string _name;
+    private readonly string _text;
+
+    public TextMapPrototype(string name, string text)
+    {
+        if (text.Length != MapService.TilesPerColumn * MapService.TilesPerRow)
+            throw new ArgumentException($"cannot load map {name}: invalid length");
+        _name = name;
+        _text = text;
+    }
+
+    public override Map CreateInstance()
+    {
+        var walls = new bool[MapService.PixelsPerRow, MapService.PixelsPerColumn];
+
+        for (ushort tileX = 0; tileX < MapService.TilesPerRow; tileX++)
+        for (ushort tileY = 0; tileY < MapService.TilesPerColumn; tileY++)
+        {
+            var tile = new TilePosition(tileX, tileY);
+            if (_text[tileX + tileY * MapService.TilesPerRow] != '#')
+                continue;
+
+            for (byte pixelInTileX = 0; pixelInTileX < MapService.TileSize; pixelInTileX++)
+            for (byte pixelInTileY = 0; pixelInTileY < MapService.TileSize; pixelInTileY++)
+            {
+                var (x, y) = tile.ToPixelPosition().GetPixelRelative(pixelInTileX, pixelInTileY);
+                walls[x, y] = true;
+            }
+        }
+
+        return new Map(_name, walls);
+    }
+}

tanks-backend/TanksServer/Graphics/Sprite.cs

@@ -26,5 +26,17 @@ internal sealed class Sprite(bool?[,] data)
     public bool? this[int x, int y] => data[x, y];
 
     public int Width => data.GetLength(0);
+
     public int Height => data.GetLength(1);
+
+    public bool[,] ToBoolArray()
+    {
+        var result = new bool[Width, Height];
+
+        for (var y = 0; y < Height; y++)
+        for (var x = 0; x < Width; x++)
+            result[x, y] = this[x, y] ?? false;
+
+        return result;
+    }
 }

tanks-backend/TanksServer/Models/PositionHelpers.cs

@@ -38,4 +38,7 @@ internal static class PositionHelpers
             pixelPosition.GetPixelRelative(add, add)
         );
     }
+
+    public static PixelPosition GetCenter(this TilePosition tile)
+        => tile.ToPixelPosition().GetPixelRelative(4, 4);
 }

tanks-backend/TanksServer/Program.cs

@@ -64,11 +64,14 @@ public static class Program
         builder.Services.AddSingleton<TankSpawnQueue>();
         builder.Services.AddSingleton<Endpoints>();
         builder.Services.AddSingleton<BufferPool>();
+        builder.Services.AddSingleton<EmptyTileFinder>();
+        builder.Services.AddSingleton<ChangeToRequestedMap>();
 
         builder.Services.AddHostedService<GameTickWorker>();
         builder.Services.AddHostedService(sp => sp.GetRequiredService<ControlsServer>());
         builder.Services.AddHostedService(sp => sp.GetRequiredService<ClientScreenServer>());
 
+        builder.Services.AddSingleton<ITickStep, ChangeToRequestedMap>(sp => sp.GetRequiredService<ChangeToRequestedMap>());
         builder.Services.AddSingleton<ITickStep, MoveBullets>();
         builder.Services.AddSingleton<ITickStep, CollideBullets>();
         builder.Services.AddSingleton<ITickStep, RotateTanks>();