do not send frames when nothing changes

DisplayCommands/ByteGrid.cs

@@ -2,7 +2,7 @@ using System.Diagnostics;
 
 namespace DisplayCommands;
 
-public class ByteGrid(ushort width, ushort height)
+public sealed class ByteGrid(ushort width, ushort height) : IEquatable<ByteGrid>
 {
     public ushort Height { get; } = height;
 
@@ -12,7 +12,7 @@ public class ByteGrid(ushort width, ushort height)
 
     public byte this[ushort x, ushort y]
     {
-        get => Data.Span[ GetIndex(x, y)];
+        get => Data.Span[GetIndex(x, y)];
         set => Data.Span[GetIndex(x, y)] = value;
     }
 
@@ -24,4 +24,16 @@ public class ByteGrid(ushort width, ushort height)
     }
 
     public void Clear() => Data.Span.Clear();
+
+    public bool Equals(ByteGrid? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return Height == other.Height && Width == other.Width && Data.Span.SequenceEqual(other.Data.Span);
+    }
+
+    public override bool Equals(object? obj) => ReferenceEquals(this, obj) || (obj is ByteGrid other && Equals(other));
+    public override int GetHashCode() => HashCode.Combine(Height, Width, Data);
+    public static bool operator ==(ByteGrid? left, ByteGrid? right) => Equals(left, right);
+    public static bool operator !=(ByteGrid? left, ByteGrid? right) => !Equals(left, right);
 }

DisplayCommands/Cp437Grid.cs

@@ -3,7 +3,7 @@ using System.Text;
 
 namespace DisplayCommands;
 
-public sealed class Cp437Grid(ushort width, ushort height)
+public sealed class Cp437Grid(ushort width, ushort height) : IEquatable<Cp437Grid>
 {
     private readonly ByteGrid _byteGrid = new(width, height);
 
@@ -47,7 +47,6 @@ public sealed class Cp437Grid(ushort width, ushort height)
         var consumed = _encoding.GetBytes(valuesStr, convertedStr);
         Debug.Assert(consumed == 1);
         return convertedStr[0];
-        
     }
 
     private char ByteToChar(byte b)
@@ -57,4 +56,16 @@ public sealed class Cp437Grid(ushort width, ushort height)
         _encoding.GetChars(valueBytes, resultStr);
         return resultStr[0];
     }
+
+    public bool Equals(Cp437Grid? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return Height == other.Height && Width == other.Width && _byteGrid.Equals(other._byteGrid);
+    }
+
+    public override bool Equals(object? obj) => ReferenceEquals(this, obj) || (obj is Cp437Grid other && Equals(other));
+    public override int GetHashCode() => HashCode.Combine(_byteGrid, Height, Width);
+    public static bool operator ==(Cp437Grid? left, Cp437Grid? right) => Equals(left, right);
+    public static bool operator !=(Cp437Grid? left, Cp437Grid? right) => !Equals(left, right);
 }

DisplayCommands/PixelGrid.cs

@@ -2,7 +2,7 @@ using System.Diagnostics;
 
 namespace DisplayCommands;
 
-public sealed class PixelGrid(ushort width, ushort height)
+public sealed class PixelGrid(ushort width, ushort height) : IEquatable<PixelGrid>
 {
     private readonly ByteGrid _byteGrid = new((ushort)(width / 8u), height);
 
@@ -34,6 +34,18 @@ public sealed class PixelGrid(ushort width, ushort height)
 
     public void Clear() => _byteGrid.Clear();
 
+    public bool Equals(PixelGrid? other)
+    {
+        if (ReferenceEquals(null, other)) return false;
+        if (ReferenceEquals(this, other)) return true;
+        return Width == other.Width && Height == other.Height && _byteGrid.Equals(other._byteGrid);
+    }
+
+    public override bool Equals(object? obj) => ReferenceEquals(this, obj) || (obj is PixelGrid other && Equals(other));
+    public override int GetHashCode() => HashCode.Combine(_byteGrid, Width, Height);
+    public static bool operator ==(PixelGrid? left, PixelGrid? right) => Equals(left, right);
+    public static bool operator !=(PixelGrid? left, PixelGrid? right) => !Equals(left, right);
+
     private (ushort byteIndex, byte bitInByteMask) GetIndexes(int x)
     {
         Debug.Assert(x < Width);

TanksServer/Interactivity/SendToServicePointDisplay.cs

@@ -13,6 +13,7 @@ internal sealed class SendToServicePointDisplay : ITickStep
     private readonly PlayerServer _players;
     private readonly ILogger<SendToServicePointDisplay> _logger;
     private readonly IDisplayConnection _displayConnection;
+    private PixelGrid? _lastSentFrame;
 
     private DateTime _nextFailLog = DateTime.Now;
 
@@ -50,7 +51,12 @@ internal sealed class SendToServicePointDisplay : ITickStep
         try
         {
             await _displayConnection.SendCp437DataAsync(MapService.TilesPerRow, 0, _scoresBuffer);
-            await _displayConnection.SendBitmapLinearWindowAsync(0, 0, _lastFinishedFrameProvider.LastFrame);
+
+            var currentFrame = _lastFinishedFrameProvider.LastFrame;
+            if (_lastSentFrame == currentFrame)
+                return;
+            _lastSentFrame = currentFrame;
+            await _displayConnection.SendBitmapLinearWindowAsync(0, 0, _lastSentFrame);
         }
         catch (SocketException ex)
         {

TanksServer/appsettings.json

@@ -24,7 +24,7 @@
     "MoveSpeed": 1.4,
     "TurnSpeed": 0.4,
     "ShootDelayMs": 400,
-    "BulletSpeed": 8
+    "BulletSpeed": 3
   },
   "Players": {
     "SpawnDelayMs": 3000,