World: load size directly from JSON.

Shared/ExtensionMethods.cs

@@ -18,6 +18,11 @@ namespace SemiColinGames {
     public static void Deconstruct(this Point point, out int x, out int y) =>
       (x, y) = (point.X, point.Y);
 
+    // Rectangle
+    public static Vector2 HalfSize(this Rectangle rect) {
+      return new Vector2(rect.Width / 2, rect.Height / 2);
+    }
+
     // SpriteFont
     public static Vector2 CenteredOn(this SpriteFont font, string text, Point position) {
       Vector2 size = font.MeasureString(text);

Shared/World.cs

@@ -25,22 +25,20 @@ namespace SemiColinGames {
     public Camera Camera { get; }
 
     // Size of World in pixels.
-    public int Width {
-      get { return gridWidth * TileSize; }
-    }
-
-    public int Height {
-      get { return gridHeight * TileSize; }
-    }
+    public readonly int Width;
+    public readonly int Height;
 
     public World(GraphicsDevice graphics, string json) {
       Camera = new Camera();
       LinesOfSight = new LinesOfSight(graphics);
 
       JObject root = JObject.Parse(json);
+      Width = root.SelectToken("width").Value<int>();
+      Height = root.SelectToken("height").Value<int>();
 
       List<Tile> hazardTiles = new List<Tile>();
       List<Tile> obstacleTiles = new List<Tile>();
+      List<Tile> obstacleTiles8 = new List<Tile>();
       List<Tile> decorationTiles = new List<Tile>();
       List<Tile> backgroundTiles = new List<Tile>();
       foreach (JToken layer in root.SelectToken("layers").Children()) {
@@ -55,6 +53,8 @@ namespace SemiColinGames {
           hazardTiles = tileList;
         } else if (layerName == "obstacles") {
           obstacleTiles = tileList;
+        } else if (layerName == "obstacles-8") {
+          obstacleTiles8 = tileList;
         } else if (layerName == "decorations") {
           decorationTiles = tileList;
         } else if (layerName == "background") {
@@ -62,6 +62,7 @@ namespace SemiColinGames {
         }
       }
       // Get all the obstacles into a single array, sorted by X.
+      obstacleTiles.AddRange(obstacleTiles8);
       obstacleTiles.AddRange(hazardTiles);
       obstacles = obstacleTiles.ToArray();
       Array.Sort(obstacles, Tile.CompareByX);
@@ -79,11 +80,10 @@ namespace SemiColinGames {
       CollisionTargets[0] = new AABB(new Vector2(-1, 0), new Vector2(1, float.MaxValue));
 
       // Now add all the normal collisionTargets for every obstacle.
-      Vector2 halfSize = new Vector2(TileSize / 2, TileSize / 2);
       for (int i = 0; i < obstacles.Length; i++) {
-        Vector2 center = new Vector2(
-          obstacles[i].Position.Left + halfSize.X, obstacles[i].Position.Top + halfSize.Y);
-        CollisionTargets[i + 1] = new AABB(center, halfSize, obstacles[i]);
+        Tile obstacle = obstacles[i];
+        CollisionTargets[i + 1] = new AABB(
+            obstacle.Position.Center.ToVector2(), obstacle.Position.HalfSize(), obstacle);
       }
 
       // Add a final synthetic collisionTarget on the right side of the world.