CustomMonoGameUtils.cs

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace C_EcoSimApp
{

    internal static class CustomMonoGameUtil
    {
        private static Texture2D _texture;
        private static Texture2D GetTexture(SpriteBatch spriteBatch)
        {
            if (_texture == null)
            {
                _texture = new Texture2D(spriteBatch.GraphicsDevice, 1, 1, false, SurfaceFormat.Color);
                _texture.SetData(new[] { Microsoft.Xna.Framework.Color.White });
            }

            return _texture;
        }

        public static void DrawLine(this SpriteBatch spriteBatch, Vector2 point1, Vector2 point2, Microsoft.Xna.Framework.Color color, float thickness = 1f)
        {
            var distance = Vector2.Distance(point1, point2);
            var angle = (float)Math.Atan2(point2.Y - point1.Y, point2.X - point1.X);
            DrawLine(spriteBatch, point1, distance, angle, color, thickness);
        }

        public static void DrawLine(this SpriteBatch spriteBatch, Vector2 point, float length, float angle, Microsoft.Xna.Framework.Color color, float thickness = 1f)
        {
            var origin = new Vector2(0f, 0.5f);
            var scale = new Vector2(length, thickness);
            spriteBatch.Draw(GetTexture(spriteBatch), point, null, color, angle, origin, scale, SpriteEffects.None, 0);
        }

        public static System.Drawing.PointF Vector2ToPoint(Vector2 vector2)
        {
            System.Drawing.PointF pt = new System.Drawing.Point(
                (int)(vector2.X + 0.5f), (int)(vector2.Y + 0.5f));
            
            return pt;
        }

        public static Vector2 ToVector2(PointF point)
        {
            return new Vector2(point.X, point.Y);
        }

        //// str - the source string
        //// index- the start location to replace at (0-based)
        //// length - the number of characters to be removed before inserting
        //// replace - the string that is replacing characters
        public static string ReplaceAt(this string str, int index, int length, string replace)
        {
            return str.Remove(index, Math.Min(length, str.Length - index))
                    .Insert(index, replace);
        }
    }

    public class SimpleFps
    {
        private double frames = 0;
        private double updates = 0;
        private double elapsed = 0;
        private double last = 0;
        private double now = 0;
        public double msgFrequency = 1.0f;
        public string msg = "";

        /// <summary>
        /// The msgFrequency here is the reporting time to update the message.
        /// </summary>
        public void Update(GameTime gameTime)
        {
            now = gameTime.TotalGameTime.TotalSeconds;
            elapsed = (double)(now - last);
            if (elapsed > msgFrequency)
            {
                msg = " Fps: " + Math.Round(frames / elapsed, 4).ToString() + "\n Elapsed time: " + Math.Round(elapsed, 4).ToString(); //+ "\n Updates: " + updates.ToString() + "\n Frames: " + frames.ToString();
                //Console.WriteLine(msg);
                elapsed = 0;
                frames = 0;
                updates = 0;
                last = now;
            }
            updates++;
        }

        public void DrawFps(SpriteBatch spriteBatch, SpriteFont font, Vector2 fpsDisplayPosition, Microsoft.Xna.Framework.Color fpsTextColor)
        {
            spriteBatch.DrawString(font, msg, fpsDisplayPosition, fpsTextColor);
            frames++;
        }
    }

    public class Camera2D
    {
        public Camera2D()
        {
            Zoom = 1;
            Position = Vector2.Zero;
            Rotation = 0;
            Origin = Vector2.Zero;
            Position = Vector2.Zero;
        }

        public float Zoom { get; set; }
        public Vector2 Position { get; set; }
        public float Rotation { get; set; }
        public Vector2 Origin { get; set; }

        public void Move(Vector2 direction)
        {
            Position += direction;
        }

        public Matrix GetTransform()
        {
            var translationMatrix = Matrix.CreateTranslation(new Vector3(Position.X, Position.Y, 0));
            var rotationMatrix = Matrix.CreateRotationZ(Rotation);
            var scaleMatrix = Matrix.CreateScale(new Vector3(Zoom, Zoom, 1));
            var originMatrix = Matrix.CreateTranslation(new Vector3(Origin.X, Origin.Y, 0));

            return translationMatrix * rotationMatrix * scaleMatrix * originMatrix;
        }
    }

}