Feature: Simplified Asteroids game inputs and improved Rating calculation.

Author: deanthecoder

G33kShell.Desktop/Console/Screensavers/AI/AiGameCanvasBase.cs

@@ -119,7 +119,7 @@ private void TrainAiImpl(Action<byte[]> saveBrainBytes)
         {
             m_generationsSinceImprovement++;
 
-            m_currentPopSize = Math.Max(m_currentPopSize - 2, MinPopSize);
+            m_currentPopSize = Math.Max(m_currentPopSize - 1, MinPopSize);
             if (m_generationsSinceImprovement >= 100)
             {
                 m_generationsSinceImprovement = 0;

G33kShell.Desktop/Console/Screensavers/Asteroids/Asteroid.cs

@@ -16,7 +16,6 @@ public class Asteroid
     private readonly float m_direction;
     private readonly Vector2[] m_offsets;
     private static readonly int[] Radii = [2, 4, MaxRadius];
-    private static readonly int[] HitScores = [20, 10, 5];
     private static readonly int[] SizeMetrics = [1, 2, 4];
     private static readonly float[] Speeds = [1.5f, 1.0f, 0.6f];
     private int m_size = 2;
@@ -25,15 +24,14 @@ public class Asteroid
 
     public int SizeMetric => SizeMetrics[m_size];
     public int Radius => Radii[m_size];
-    public int HitScore => HitScores[m_size];
     public bool IsInvulnerable => m_invulnerable > 0;
 
     /// <summary>
     /// Position in arena coordinates.
     /// </summary>
     public Vector2 Position { get; private set; }
 
-    private Vector2 Velocity
+    public Vector2 Velocity
     {
         get
         {

G33kShell.Desktop/Console/Screensavers/Asteroids/Brain.cs

@@ -15,9 +15,9 @@ namespace G33kShell.Desktop.Console.Screensavers.Asteroids;
 
 public class Brain : AiBrainBase
 {
-    public const int BrainInputCount = 10;
+    public const int BrainInputCount = 6;
 
-    public Brain() : base(BrainInputCount, [32, 16], 4)
+    public Brain() : base(BrainInputCount, [16, 8], 4)
     {
     }
 

G33kShell.Desktop/Console/Screensavers/Asteroids/Bullet.cs

@@ -26,18 +26,12 @@ public class Bullet
     public Vector2 Position { get; private set; }
 
     public bool IsExpired { get; private set; }
-
-    /// <summary>
-    /// The target the bullet is nominally aiming for.
-    /// </summary>
-    public Asteroid Target { get; }
-
-    public Bullet(Vector2 position, float theta, Asteroid target, int arenaWidth, int arenaHeight)
+    
+    public Bullet(Vector2 position, float theta, int arenaWidth, int arenaHeight)
     {
         m_arenaWidth = arenaWidth;
         m_arenaHeight = arenaHeight;
         Position = position;
-        Target = target;
         m_velocity = theta.ToDirection();
         m_distanceUntilDeath = new Vector2(arenaWidth, arenaHeight).Length() * 0.4;
     }

G33kShell.Desktop/Console/Screensavers/Asteroids/Game.cs

@@ -21,8 +21,6 @@ namespace G33kShell.Desktop.Console.Screensavers.Asteroids;
 public class Game : AiGameBase
 {
     private int m_bulletsFired;
-    private int m_asteroidsHit;
-    private int m_perfectHits;
     private int m_gameTicks;
     private int m_leftTurns;
     private int m_rightTurns;
@@ -39,33 +37,19 @@ public override double Rating
     {
         get
         {
-            if (Score == 0)
-                return 0.0; // Penalize pacifists.
-            if (m_gameTicks > 2000 && m_bulletsFired < 5)
-                return 0.0; // Penalize idle campers.
             if (TurnEquality < 0.3)
                 return 0.0; // Penalize wonky-turners.
             if (m_thrustTicks == 0)
                 return 0.0; // Penalize non-thrusters.
 
-            var thrustRatio = m_thrustTicks / (double)m_gameTicks;
-            var survivalBonus = (m_gameTicks / 8000.0).Clamp(0.0, 1.0);
-
-            return Score / 8000.0 * 10.0 +
-                   HitRatio * 0.5 * 0.1 +
-                   PerfectHitRatio * 1.0 * 0.1 +
-                   thrustRatio * 2.0 * 0.1 +
-                   TurnEquality * 0.5 * 0.1 +
-                   survivalBonus * 1.0 * 0.1
-                   ;
+            return Score * HitRatio * HitRatio * m_gameTicks * 0.001;
         }
     }
 
     public override IEnumerable<(string Name, string Value)> ExtraGameStats()
     {
         yield return ("Score", Score.ToString());
-        yield return ("Accuracy", HitRatio.ToString("P1"));
-        yield return ("Perfect", PerfectHitRatio.ToString("P1"));
+        yield return ("HitRatio", HitRatio.ToString("P1"));
         yield return ("Ticks", m_gameTicks.ToString());
         yield return ("TurnEquality", TurnEquality.ToString("P1"));
         yield return ("Thrusts", m_thrustTicks.ToString());
@@ -87,8 +71,7 @@ private double TurnEquality
     public List<Asteroid> Asteroids { get; } = [];
     public List<Bullet> Bullets { get; } = [];
 
-    private double PerfectHitRatio => m_bulletsFired == 0 ? 0.0 : (double)m_perfectHits / m_bulletsFired;
-    private double HitRatio => m_bulletsFired == 0 ? 0.0 : (double)m_asteroidsHit / m_bulletsFired;
+    private double HitRatio => m_bulletsFired == 0 ? 0.0 : (double)Score / m_bulletsFired;
 
     public Game(int arenaWidth, int arenaHeight) : base(arenaWidth, arenaHeight, new Brain())
     {
@@ -98,13 +81,11 @@ public override Game ResetGame()
     {
         Ship = new Ship(ArenaWidth, ArenaHeight);
         Score = 0;
-        m_gameState = new GameState(Ship, Asteroids, Bullets, ArenaWidth, ArenaHeight);
+        m_gameState = new GameState(Ship, Asteroids, ArenaWidth, ArenaHeight);
 
         Asteroids.Clear();
         Bullets.Clear();
         m_bulletsFired = 0;
-        m_perfectHits = 0;
-        m_asteroidsHit = 0;
         m_gameTicks = 0;
         m_leftTurns = 0;
         m_rightTurns = 0;
@@ -151,8 +132,7 @@ public override void Tick()
         // Spawn new bullets.
         if (Ship.IsShooting && Bullets.Count < Ship.MaxBullets)
         {
-            var target = Asteroids.FastFindMin(o => Vector2.DistanceSquared(Ship.Position, o.Position));
-            Bullets.Add(new Bullet(Ship.Position, Ship.Theta, target, ArenaWidth, ArenaHeight));
+            Bullets.Add(new Bullet(Ship.Position, Ship.Theta, ArenaWidth, ArenaHeight));
             m_bulletsFired++;
         }
 
@@ -189,12 +169,7 @@ public override void Tick()
             // Bullet hit an asteroid.
             bulletsToRemove.Add(bullet);
             hitAsteroid.Explode(Asteroids);
-            Score += hitAsteroid.HitScore;
-
-            // Bonus points if it was the asteroid we were aiming for.
-            if (bullet.Target == hitAsteroid)
-                m_perfectHits++;
-            m_asteroidsHit++;
+            Score++;
         }
 
         for (var i = 0; i < bulletsToRemove.Count; i++)

G33kShell.Desktop/Console/Screensavers/Asteroids/GameState.cs

@@ -24,14 +24,12 @@ public class GameState : IAiGameState
     private readonly double[] m_inputVector = new double[Brain.BrainInputCount];
     private readonly Ship m_ship;
     private readonly List<Asteroid> m_asteroids;
-    private readonly List<Bullet> m_bullets;
     private readonly float m_arenaDiagonal;
 
-    public GameState(Ship ship, List<Asteroid> asteroids, List<Bullet> bullets, int arenaWidth, int arenaHeight)
+    public GameState(Ship ship, List<Asteroid> asteroids, int arenaWidth, int arenaHeight)
     {
         m_ship = ship;
         m_asteroids = asteroids;
-        m_bullets = bullets;
 
         m_arenaDiagonal = new Vector2(arenaWidth, arenaHeight).Length();
     }
@@ -56,19 +54,11 @@ public double[] ToInputVector()
             m_inputVector[2] = 0.0;
         }
 
-        var normalizedVelocity = m_ship.Velocity == Vector2.Zero ? Vector2.Zero : Vector2.Normalize(m_ship.Velocity);
-        m_inputVector[3] = normalizedVelocity.X.Clamp(-1.0f, 1.0f);
-        m_inputVector[4] = normalizedVelocity.Y.Clamp(-1.0f, 1.0f);
+        var relativeVelocity = asteroid?.Velocity ?? Vector2.Zero - m_ship.Velocity;
+        relativeVelocity = relativeVelocity.LengthSquared() > 0.0f ? Vector2.Normalize(relativeVelocity) : Vector2.Zero;
+        m_inputVector[3] = relativeVelocity.X.Clamp(-1.0f, 1.0f);
+        m_inputVector[4] = relativeVelocity.Y.Clamp(-1.0f, 1.0f);
         m_inputVector[5] = (m_ship.Theta / Math.Tau).Clamp(-1.0f, 1.0f);
-        m_inputVector[6] = m_ship.IsShooting ? 1.0 : 0.0;
-        m_inputVector[7] = m_ship.IsThrusting ? 1.0 : 0.0;
-        m_inputVector[8] = m_ship.Turning switch
-        {
-            Ship.Turn.Left => -1.0,
-            Ship.Turn.Right => 1.0,
-            _ => 0.0
-        };
-        m_inputVector[9] = (double)m_bullets.Count / Ship.MaxBullets;
 
         return m_inputVector;
     }