Implemented scren shake in the Camera2D class

Camera2D.cs

@@ -12,6 +12,15 @@ namespace LunaLightXMG
         private float rotation;
         private Vector2 position;
         private Rectangle levelBounds;
+        private readonly float camSpeed = 0.1f;
+
+        // Screen Shake
+        private float shakeTimeRemaining = 0f;
+        private float shakeMagnitudeCurrent = 0f;
+        private bool shaking = false;
+        
+        // Util
+        Utilities util;
         
         // Getters and setters
         public Vector2 Position
@@ -33,11 +42,12 @@ namespace LunaLightXMG
         // constructor
         public Camera2D(int width, int height)
         {
-            this.viewport = new Viewport(0, 0, width, height);
+            viewport = new Viewport(0, 0, width, height);
             levelBounds = new Rectangle(0, 0, 320, 180); // Default
             zoom = 1f;
             rotation = 0f;
             position = Vector2.Zero;
+            util = new Utilities();
         }
         
         public Matrix GetViewMatrix()
@@ -56,12 +66,46 @@ namespace LunaLightXMG
 
         public void Follow(Vector2 targetPostion)
         {
-            // temp code
-            Vector2 smoothPosition = Vector2.Lerp(position, targetPostion, 0.1f);
-            position = smoothPosition;
+            position += (targetPostion - position) * camSpeed;
+            if (Math.Abs(position.X - targetPostion.X) < 0.1f) 
+            {
+                position.X = targetPostion.X;
+            }
+            if (Math.Abs(position.Y - targetPostion.Y) < 0.1f) 
+            {
+                position.Y = targetPostion.Y;
+            }
             ClampToBounds();
         }
         
+        public void ScreenShake(float shakeTime, float shakeMagnitude)
+        {
+            shakeTimeRemaining = shakeTime;
+            shakeMagnitudeCurrent = shakeMagnitude;
+            shaking = true;
+        }
+        
+        public void UpdateScreenShake(GameTime gameTime)
+        {
+            if (!shaking) return;
+
+            if (shakeTimeRemaining > 0)
+            {
+                float shakeX = util.ChooseFromRange(-shakeMagnitudeCurrent, shakeMagnitudeCurrent);
+                float shakeY = util.ChooseFromRange(-shakeMagnitudeCurrent, shakeMagnitudeCurrent);
+                position.X += shakeX;
+                position.Y += shakeY;
+                shakeTimeRemaining -= (float)gameTime.ElapsedGameTime.TotalSeconds;
+                shakeMagnitudeCurrent *= 0.9f;
+            }
+            else
+            {
+                shaking = false;
+                shakeTimeRemaining = 0f;
+                shakeMagnitudeCurrent = 0f;
+            }
+        }
+
         private void ClampToBounds()
         {
             // Calculate the cam's half viewport size

LunaLightGame.cs

@@ -44,8 +44,8 @@ namespace LunaLightXMG
         private SpriteFont debugFont;
         private Texture2D debugGrid;
 
-        // Utility
-        private static Random random; 
+        // Util
+        Utilities util;
         
         public LunaLightGame()
         {
@@ -63,11 +63,11 @@ namespace LunaLightXMG
             playerInput = new PlayerInput();
             enemies = new List<Enemy>();
 
-            random = new Random(42);
-
             // Init number of platforms / enemies
             numOfPlatforms = 4;
             numOfEnemies = 10;
+
+            util = new Utilities();
         }
         
         protected override void Initialize()
@@ -103,7 +103,7 @@ namespace LunaLightXMG
             var KeyB = keyboardState.IsKeyDown(Keys.B);
             var KeyN = keyboardState.IsKeyDown(Keys.N);
             var KeyM = keyboardState.IsKeyDown(Keys.M);
-            
+            var KeyP = keyboardState.IsKeyDown(Keys.P);
             if (KeyK)
             {
                 camera2D.Rotation -= 0.01f;
@@ -124,6 +124,10 @@ namespace LunaLightXMG
             {
                 renderHandler.ZoomOut();
             }
+            if (KeyP)
+            {
+                camera2D.ScreenShake(0.5f, 5f);
+            }
         }
         // ---------------------------------------
         protected override void LoadContent()
@@ -169,6 +173,7 @@ namespace LunaLightXMG
             renderHandler.UpdateZoom();
             // Update camera position
             camera2D.Follow(player.position);
+            camera2D.UpdateScreenShake(gameTime);
             // camera testing
             TestCameraWhilePlaying();
             
@@ -211,7 +216,7 @@ namespace LunaLightXMG
             for (int i = 0; i < numberOfEnemies; i++)
             {
                 Vector2 spawnPosition = new Vector2(16 + i * 3, -16);
-                Enemy enemy = new Enemy(spawnPosition, GetRandomValueBetween1And3());
+                Enemy enemy = new(spawnPosition, util.ChooseFromRange(1,3));
                 enemy.LoadContent(Content);
                 enemies.Add(enemy);
             }
@@ -258,16 +263,11 @@ namespace LunaLightXMG
             
 
             spriteBatch.DrawString(debugFont, $"Camera Rotation Control - Rotate left: K, Rotate right: L", new Vector2(10, 190), Color.White);
-
             spriteBatch.DrawString(debugFont, $"Render Target Zoom Control - Zoom in: B, Zoom normal: N, Zoom out: M", new Vector2(10, 210), Color.White);
-            
+            spriteBatch.DrawString(debugFont, $"Press P to test screen shake.", new Vector2(10, 230), Color.White);
             spriteBatch.End();
         }
         
-        public static float GetRandomValueBetween1And3()
-        {
-            return (float)(1 + 2 * random.NextDouble());
-        }
         private void ResetGame()
         {
             // reset cam

UpdateNotes/Camera2D.md

@@ -31,3 +31,19 @@ Solutions:
 - We should in either case only zoom at integer values to preserve pixel-perfect zoom.
 
 Leaning towards abstracting the render target code to its own class and handling zoom there. Overall I think this will be better as it is what draws to the backbuffer.
+
+## March 19th, 2025 - JME
+
+**ScreenShake**
+
+I have already done this in the GML version however it has to be reimplemented to work with our current class structure. We should be able to add a ScreenShake() function to the Camera2D class that takes in shake time and shake magnitude arguments. 
+
+The function will work by randomly changing the cam position between the current position + magnitude and current position - magnitude. We already have a nice function written in our LunaLigthGame class that randomly chooses a number between to set numbers. **side note** It might be nice to create a utility class and move this function over there so we can use it from anywehre.
+
+**Refining camera movement a bit**
+
+When the player stops the camera slows to a stop. This is good except that in the last few mometns the camera gets kinda shakey beacause the Lerp() function we are using calculates to the 5th decimal and as it approaches the final postion the camera jumps from pixel to pixel slowly. 
+
+Rather than use Lerp() let's explicitly define our follow code and once the cam position is witin a certain threshold of target position we can snap it to the target position.
+
+**Needs more refinement**

Utilities.cs

@@ -0,0 +1,19 @@
+using System;
+
+namespace LunaLightXMG
+{
+    public class Utilities
+    {
+        private Random random;
+
+        public Utilities(int seed = 42)
+        {
+            random = new Random(seed);
+        }
+
+        public float ChooseFromRange(float num1, float num2)
+        {
+            return (float)(num1 + (num2 - num1) * random.NextDouble());
+        }
+    }
+}