/// <inheritdoc/>
public float4 Execute()
{
float2 scenePos = D2D.GetScenePosition().XY;
float xo = scenePos.X - (this.width >> 1);
float yo = scenePos.Y - (this.height >> 1);
float rm = 0.5f * this.diameter;
float km = 0.7f / this.diameter * MathF.PI;
float w = rm / 10.0f;
float yd = yo * yo;
float xd = xo * xo;
float d = xd + yd;
float v = 1.0f + (1.0f + Hlsl.Tanh((rm - Hlsl.Sqrt(d)) / w)) * Hlsl.Sin(km * d) * 0.5f;
return(new Float4(v, v, v, 1.0f));
}