clamp player movement to world

Shared/ShmupScene.cs

@@ -8,17 +8,17 @@ namespace SemiColinGames {
 
     const float DESIRED_ASPECT_RATIO = 1920.0f / 1080.0f;
 
-    private readonly Color backgroundColor = Color.DarkBlue;
+    private readonly Color backgroundColor = Color.Black;
 
     private readonly GraphicsDevice graphics;
     private readonly RenderTarget2D sceneTarget;
     private readonly SpriteBatch spriteBatch;
 
-    public ShmupScene(GraphicsDevice graphics) {
+    public ShmupScene(GraphicsDevice graphics, Point worldSize) {
       this.graphics = graphics;
 
       sceneTarget = new RenderTarget2D(
-        graphics, 1920 / 4, 1080 / 4, false /* mipmap */,
+        graphics, worldSize.X, worldSize.Y, false /* mipmap */,
         graphics.PresentationParameters.BackBufferFormat, DepthFormat.Depth24);
       spriteBatch = new SpriteBatch(graphics);
     }
@@ -28,6 +28,8 @@ namespace SemiColinGames {
     }
 
     public void Dispose() {
+      sceneTarget.Dispose();
+      spriteBatch.Dispose();
       GC.SuppressFinalize(this);
     }
 
@@ -43,7 +45,12 @@ namespace SemiColinGames {
       spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.AlphaBlend,
           SamplerState.PointClamp, DepthStencilState.Default,
           RasterizerState.CullNone);
-      spriteBatch.Draw(Textures.Yellow2.Get, Vector2.Floor(world.Player.Position), Color.White);
+
+      // Draw player.
+      Texture2D playerTexture = world.Player.Texture.Get;
+      Vector2 spriteCenter = new Vector2(playerTexture.Width / 2, playerTexture.Height / 2);
+      Vector2 drawPos = Vector2.Floor(Vector2.Subtract(world.Player.Position, spriteCenter));
+      spriteBatch.Draw(playerTexture, drawPos, Color.White);
       spriteBatch.End();
 
       // Get ready to draw sceneTarget to screen.

Shared/ShmupWorld.cs

@@ -5,14 +5,18 @@ using System.Collections.Generic;
 
 namespace SemiColinGames {
   public sealed class ShmupWorld : IWorld {
-    public struct ShmupPlayer {
+    public class ShmupPlayer {
+      public TextureRef Texture = Textures.Yellow2;
       // Center of player sprite.
-      public Vector2 Position;
+      public Vector2 Position = new Vector2(32, 1080 / 8);
+      public Vector2 HalfSize = new Vector2(16, 10);
     }
 
-    public ShmupPlayer Player;
+    public readonly Point Size;
+    public readonly ShmupPlayer Player;
 
     public ShmupWorld() {
+      Size = new Point(1920 / 4, 1080 / 4);
       Player = new ShmupPlayer();
     }
 
@@ -28,6 +32,11 @@ namespace SemiColinGames {
       float speed = 150f;
       Vector2 motion = Vector2.Multiply(input[0].Motion, modelTime * speed);
       Player.Position = Vector2.Add(Player.Position, motion);
+      Player.Position.X = Math.Max(Player.Position.X, Player.HalfSize.X);
+      Player.Position.X = Math.Min(Player.Position.X, Size.X - Player.HalfSize.X);
+      Player.Position.Y = Math.Max(Player.Position.Y, Player.HalfSize.Y);
+      Player.Position.Y = Math.Min(Player.Position.Y, Size.Y - Player.HalfSize.Y);
+
     }
   }
 }

Shared/SneakGame.cs

@@ -70,7 +70,7 @@ namespace SemiColinGames {
       scene?.Dispose();
       // scene = new SneakScene(GraphicsDevice, ((SneakWorld) world).Camera);
       // scene = new TreeScene(GraphicsDevice);
-      scene = new ShmupScene(GraphicsDevice);
+      scene = new ShmupScene(GraphicsDevice, ((ShmupWorld) world).Size);
 
       GC.Collect();
       GC.WaitForPendingFinalizers();