Tiles can now be obstacles (in the foreground) or decorations (in the background).

Updated Levels to show off some of these.

GitOrigin-RevId: d8d04410c1

Shared/Levels.cs

@@ -12,15 +12,15 @@
 5
 6
 7
-8      <===X===>    <======================>
-9
-0
-1                      
-2         
-3                        dfffxfffxfffb                       
-===================>    <=============>    <================================================================================================
-...................]    [..............^^^^.................................................................................................
-....................~`~`....................................................................................................................";
+8      <=X=X=X=>        <=============>      (__________)
+9                                            /          \
+0                                            |          |
+1                                            |          |
+2                                            |          |
+3   dfffxfffxfffb        dfffxfffxfffb       v          v
+=================>      <=============>    <================================================================================================
+..................~`~`~`...............^^^^.................................................................................................
+..................======....................................................................................................................";
 
 
     public const string ROCKS = @"

Shared/Scene.cs

@@ -76,17 +76,17 @@ namespace SemiColinGames {
 
       // Set up transformation matrix for drawing world objects.
       Matrix transform = Matrix.CreateTranslation(-camera.Left, -camera.Top, 0);
-
-      // Draw player.
       spriteBatch.Begin(
           SpriteSortMode.Deferred, null, SamplerState.LinearWrap, null, null, null, transform);
+
+      // Draw background tiles.
+      world.DrawBackground(spriteBatch);
+
+      // Draw player.
       player.Draw(spriteBatch);
-      spriteBatch.End();
 
       // Draw foreground tiles.
-      spriteBatch.Begin(
-          SpriteSortMode.Deferred, null, SamplerState.LinearWrap, null, null, null, transform);
-      world.Draw(spriteBatch);
+      world.DrawForeground(spriteBatch);
       spriteBatch.End();
 
       // Draw debug rects & lines on top.

Shared/World.cs

@@ -5,25 +5,49 @@ using System.Collections.Generic;
 using System.Linq;
 
 namespace SemiColinGames {
-  enum Terrain {
-    Grass,
-    GrassL,
-    GrassR,
-    Rock,
-    RockL,
-    RockR,
-    WaterL,
-    WaterR,
-    Block,
-    Spike,
-    Wood,
-    WoodL,
-    WoodR,
-    WoodVert,
-    FenceL,
-    Fence,
-    FencePost,
-    FenceR,
+  class Terrain {
+
+    public static Terrain FromSymbol(char symbol) {
+      if (mapping.ContainsKey(symbol)) {
+        return mapping[symbol];
+      } else {
+        return null;
+      }
+    }
+
+    private static Dictionary<char, Terrain> mapping = new Dictionary<char, Terrain>();
+
+    public static Terrain Grass = new Terrain('=', true);
+    public static Terrain GrassL = new Terrain('<', true);
+    public static Terrain GrassR = new Terrain('>', true);
+    public static Terrain Rock = new Terrain('.', true);
+    public static Terrain RockL = new Terrain('[', true);
+    public static Terrain RockR = new Terrain(']', true);
+    public static Terrain WaterL = new Terrain('~', false);
+    public static Terrain WaterR = new Terrain('`', false);
+    public static Terrain Block = new Terrain('X', true);
+    public static Terrain Spike = new Terrain('^', true);
+    public static Terrain Wood = new Terrain('_', true);
+    public static Terrain WoodL = new Terrain('(', true);
+    public static Terrain WoodR = new Terrain(')', true);
+    public static Terrain WoodVert = new Terrain('|', false);
+    public static Terrain WoodVertL = new Terrain('/', false);
+    public static Terrain WoodVertR = new Terrain('\\', false);
+    public static Terrain WoodBottom = new Terrain('v', false);
+    public static Terrain FenceL = new Terrain('d', false);
+    public static Terrain Fence = new Terrain('f', false);
+    public static Terrain FencePost = new Terrain('x', false);
+    public static Terrain FenceR = new Terrain('b', false);
+
+    public bool IsObstacle { get; private set; }
+
+    private Terrain(char symbol, bool isObstacle) {
+      if (mapping.ContainsKey(symbol)) {
+        throw new ArgumentException("already have a terrain with symbol " + symbol);
+      }
+      IsObstacle = isObstacle;
+      mapping[symbol] = this;
+    }
   }
 
   class TileFactory {
@@ -56,6 +80,9 @@ namespace SemiColinGames {
         { Terrain.WoodL, GetTextureSource(Textures.Grassland, 9, 3) },
         { Terrain.WoodR, GetTextureSource(Textures.Grassland, 12, 3) },
         { Terrain.WoodVert, GetTextureSource(Textures.Grassland, 9, 5) },
+        { Terrain.WoodVertL, GetTextureSource(Textures.Grassland, 9, 4) },
+        { Terrain.WoodVertR, GetTextureSource(Textures.Grassland, 12, 4) },
+        { Terrain.WoodBottom, GetTextureSource(Textures.Grassland, 10, 5) },
         { Terrain.FenceL, GetTextureSource(Textures.Grassland, 5, 4) },
         { Terrain.Fence, GetTextureSource(Textures.Grassland, 6, 4) },
         { Terrain.FencePost, GetTextureSource(Textures.Grassland, 7, 4) },
@@ -98,6 +125,7 @@ namespace SemiColinGames {
 
     public const int TileSize = 16;
     readonly Tile[] tiles;
+    readonly Tile[] decorations;
 
     // Size of World in terms of tile grid.
     private readonly int tileWidth;
@@ -112,31 +140,10 @@ namespace SemiColinGames {
       get { return tileHeight * TileSize; }
     }
 
-    private static readonly Dictionary<char, Terrain> charToTerrain =
-        new Dictionary<char, Terrain>() {
-      { '=', Terrain.Grass },
-      { '<', Terrain.GrassL },
-      { '>', Terrain.GrassR },
-      { '.', Terrain.Rock },
-      { '[', Terrain.RockL },
-      { ']', Terrain.RockR },
-      { '~', Terrain.WaterL },
-      { '`', Terrain.WaterR },
-      { 'X', Terrain.Block },
-      { '^', Terrain.Spike },
-      { '_', Terrain.Wood },
-      { '(', Terrain.WoodL },
-      { ')', Terrain.WoodR },
-      { '|', Terrain.WoodVert },
-      { 'd', Terrain.FenceL },
-      { 'f', Terrain.Fence },
-      { 'x', Terrain.FencePost },
-      { 'b', Terrain.FenceR },
-    };
-
     public World(string levelSpecification) {
       TileFactory factory = new TileFactory();
       var tilesList = new List<Tile>();
+      var decorationsList = new List<Tile>();
       string[] worldDesc = levelSpecification.Split('\n');
       tileWidth = worldDesc.AsQueryable().Max(a => a.Length);
       tileHeight = worldDesc.Length;
@@ -145,15 +152,21 @@ namespace SemiColinGames {
         for (int j = 0; j < tileHeight; j++) {
           if (i < worldDesc[j].Length) {
             char key = worldDesc[j][i];
-            if (charToTerrain.ContainsKey(key)) {
-              Terrain terrain = charToTerrain[key];
+            Terrain terrain = Terrain.FromSymbol(key);
+            if (terrain != null) {
               var position = new Rectangle(i * TileSize, j * TileSize, TileSize, TileSize);
-              tilesList.Add(factory.MakeTile(terrain, position));
+              Tile tile = factory.MakeTile(terrain, position);
+              if (tile.Terrain.IsObstacle) {
+                tilesList.Add(tile);
+              } else {
+                decorationsList.Add(tile);
+              }
             }
           }
         }
       }
       tiles = tilesList.ToArray();
+      decorations = decorationsList.ToArray();
 
       // Because we added tiles from left to right, the CollisionTargets are sorted by x-position.
       // We maintain this invariant so that it's possible to efficiently find CollisionTargets that
@@ -176,7 +189,13 @@ namespace SemiColinGames {
           new Vector2(Width + 1, 0), new Vector2(1, float.MaxValue));
     }
 
-    public void Draw(SpriteBatch spriteBatch) {
+    public void DrawBackground(SpriteBatch spriteBatch) {
+      foreach (Tile t in decorations) {
+        t.Draw(spriteBatch);
+      }
+    }
+
+    public void DrawForeground(SpriteBatch spriteBatch) {
       foreach (Tile t in tiles) {
         t.Draw(spriteBatch);
       }