Camera.cs

using Microsoft.Xna.Framework;
using System;

namespace Game1
{
    internal class Camera
    {
        internal Transform transform;
        float nearPlaneDistance = 0.1f;
        internal float NearPlaneDistance
        {
            get
            {
                return nearPlaneDistance;
            }
            set
            {
                nearPlaneDistance = value;
                CreateProjection();
            }
        }
        float farPlaneDistance = 1000000000.0f;
        internal float FarPlaneDistance
        {
            get
            {
                return farPlaneDistance;
            }
            set
            {
                farPlaneDistance = value;
                CreateProjection();
            }
        }
        internal Matrix View
        {
            get { return transform.Matrix; }
        }
        Matrix projection;
        internal Matrix Projection
        {
            get { return projection; }
        }
        float fieldOfView = MathHelper.ToRadians(60f);
        internal float FieldOfView
        {
            get
            {
                return MathHelper.ToDegrees(fieldOfView);
            }
            set
            {
                fieldOfView = MathHelper.ToRadians(value);
                CreateProjection();
            }
        }
        internal Vector3 destination;
        internal float speed;

        internal Camera()
        {
            Game1.graphics.GraphicsDevice.DeviceReset += (e, s) => CreateProjection();
            Game1.window.ClientSizeChanged += (e, s) => CreateProjection();
            transform = new Transform();
            destination = new Vector3(0, 500, 0);
            transform.Position = new Vector3(0, 500, 0);
            speed = 1;
            CreateProjection();
        }
        void CreateProjection()
        {
            projection = Matrix.CreatePerspectiveFieldOfView(fieldOfView, Game1.graphics.GraphicsDevice.Viewport.AspectRatio, nearPlaneDistance, farPlaneDistance);
            Console.WriteLine("Changed Projection Matrix");
        }
        internal void Update()
        {
            SmoothMotion();
        }
        void SmoothMotion()
        {
            // Smoothly transition from current position to destination.
            if (Vector3.Distance(transform.Position, destination) > 1/300f)
            {
                transform.Position = Vector3.Lerp(transform.Position, destination, (float)Game1.gameTime.ElapsedGameTime.TotalSeconds * speed);
            }
            // Snap camera if withithin 1/300 of a unit.
            else
            {
                if (transform.Position != destination)
                {
                    transform.Position = destination;
                }
            }
        }
    }
}