namespace MonoGame.Extended.Particles.Modifiers.Interpolators { public class OpacityInterpolator : IInterpolator { private float _delta; public float StartValue { get; set; } public float EndValue { get { return _delta + StartValue; } set { _delta = value - StartValue; } } public unsafe void Update(float amount, Particle* particle) { particle->Opacity = _delta*amount + StartValue; } } }