sneak/Jumpy.Shared/Debug.cs

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using System.Collections.Generic;

namespace Jumpy {
  // TODO: add a WriteLine sort of functionality.
  static class Debug {
    struct DebugRect {
      public Rectangle rect;
      public Color color;

      public DebugRect(Rectangle rect, Color color) {
        this.rect = rect;
        this.color = color;
      }
    }

    public static bool Enabled;
    static List<DebugRect> rects = new List<DebugRect>();
    static Texture2D whiteTexture;
    static string toast = null;

    public static void Toast(string s) {
      toast = s;
    }

    public static void WriteLine(string s) {
      System.Diagnostics.Debug.WriteLine(s);
    }

    public static void WriteLine(string s, params object[] args) {
      System.Diagnostics.Debug.WriteLine(s, args);
    }
    
    public static void Initialize(GraphicsDevice graphics) {
      whiteTexture = new Texture2D(graphics, 1, 1);
      whiteTexture.SetData(new Color[] { Color.White });
    }
    
    public static void Clear() {
      rects.Clear();
    }

    public static void AddRect(Rectangle rect, Color color) {
      rects.Add(new DebugRect(rect, color));
    }

    public static void DrawToast(SpriteBatch spriteBatch, SpriteFont font) {
      // TODO: this use of toast isn't thread-safe.
      if (toast == null) {
        return;
      }
      spriteBatch.DrawString(font, toast, new Vector2(10, 10), Color.YellowGreen);
      toast = null;
    }

    public static void Draw(SpriteBatch spriteBatch, Camera camera) {
      if (!Enabled) {
        return;
      }
      foreach (var debugRect in rects) {
        var rect = debugRect.rect;
        rect.Offset(-camera.Left, 0);
        var color = debugRect.color;
        // top side
        spriteBatch.Draw(
          whiteTexture, new Rectangle(rect.Left, rect.Top, rect.Width, 1), color);
        // bottom side
        spriteBatch.Draw(
          whiteTexture, new Rectangle(rect.Left, rect.Bottom - 1, rect.Width, 1), color);
        // left side
        spriteBatch.Draw(
          whiteTexture, new Rectangle(rect.Left, rect.Top, 1, rect.Height), color);
        // right side
        spriteBatch.Draw(
          whiteTexture, new Rectangle(rect.Right - 1, rect.Top, 1, rect.Height), color);
      }
    }
  }
}