Debug: turn functions into noops if not compiled with DEBUG.

Fixes #11.

Shared/Debug.cs

@@ -32,23 +32,30 @@ namespace SemiColinGames {
     // Lines in excess of MAX_LINES get dropped on the floor.
     const int MAX_LINES = 2000;
     const int MAX_LINE_VERTICES = MAX_LINES * 2;
+
     static int lineIdx = 0;
-    static readonly VertexPositionColor[] lineVertices = new VertexPositionColor[MAX_LINE_VERTICES];
+    static VertexPositionColor[] lineVertices;
     static VertexBuffer vertexBuffer;
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void Initialize(GraphicsDevice graphics) {
+      lineVertices = new VertexPositionColor[MAX_LINE_VERTICES];
+      vertexBuffer?.Dispose();
       vertexBuffer = new VertexBuffer(
           graphics, typeof(VertexPositionColor), MAX_LINE_VERTICES, BufferUsage.WriteOnly);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void WriteLine(string s) {
       System.Diagnostics.Debug.WriteLine(s);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void WriteLine(string s, params object[] args) {
       System.Diagnostics.Debug.WriteLine(s, args);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void Clear(bool paused) {
       toasts.Clear();
       if (!paused) {
@@ -56,15 +63,18 @@ namespace SemiColinGames {
       }
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddToast(string s) {
       toasts.AddLast(s);
     }
 
     // FPS text is always displayed as the first toast (if set).
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void SetFpsText(string s) {
       toasts.AddFirst(s);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddRect(Rectangle rect, Color color) {
       AddLine(rect.Left, rect.Top + 1, rect.Right, rect.Top + 1, color);
       AddLine(rect.Left + 1, rect.Top + 1, rect.Left + 1, rect.Bottom, color);
@@ -72,6 +82,7 @@ namespace SemiColinGames {
       AddLine(rect.Left + 1, rect.Bottom, rect.Right, rect.Bottom, color);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddRect(AABB box, Color color) {
       Rectangle rect = new Rectangle(
           (int) (box.Position.X - box.HalfSize.X), (int) (box.Position.Y - box.HalfSize.Y),
@@ -79,6 +90,7 @@ namespace SemiColinGames {
       AddRect(rect, color);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddLine(Point start, Point end, Color color) {
       if (lineIdx >= MAX_LINE_VERTICES) {
         return;
@@ -88,14 +100,17 @@ namespace SemiColinGames {
       lineIdx += 2;
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddLine(int p1x, int p1y, int p2x, int p2y, Color color) {
       AddLine(new Point(p1x, p1y), new Point(p2x, p2y), color);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void AddLine(Vector2 start, Vector2 end, Color color) {
       AddLine(start.ToPoint(), end.ToPoint(), color);
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void DrawToasts(SpriteBatch spriteBatch) {
       if (!Enabled) {
         return;
@@ -111,6 +126,7 @@ namespace SemiColinGames {
       }
     }
 
+    [System.Diagnostics.Conditional("DEBUG")]
     public static void Draw(GraphicsDevice graphics, BasicEffect lightingEffect) {
       if (!Enabled) {
         return;