Encapsulate calculations and graph logic

13_Bounce/csharp/Bounce.cs

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+namespace Bounce;
+
+/// <summary>
+/// Represents the bounce of the ball, calculating duration, height and position in time.
+/// </summary>
+/// <remarks>
+/// All calculations are derived from the equation for projectile motion: s = vt + 0.5at^2
+/// </remarks>
+internal class Bounce
+{
+    private const float _acceleration = -32; // feet/s^2
+
+    private readonly float _velocity;
+
+    internal Bounce(float velocity)
+    {
+        _velocity = velocity;
+    }
+
+    public float Duration => -2 * _velocity / _acceleration;
+
+    public float MaxHeight =>
+        (float)Math.Round(-_velocity * _velocity / 2 / _acceleration, MidpointRounding.AwayFromZero);
+
+    public float Plot(Graph graph, float startTime)
+    {
+        var time = 0f;
+        for (; time <= Duration; time += graph.TimeIncrement)
+        {
+            var height = _velocity * time + _acceleration * time * time / 2;
+            graph.Plot(startTime + time, height);
+        }
+
+        return startTime + time;
+    }
+
+    public Bounce Next(float elasticity) => new Bounce(_velocity * elasticity);
+}