/// <summary>
/// Adds a sphere to the ray tracer.
/// </summary>
/// <param name="dXPos"></param>
/// <param name="dYPos"></param>
/// <param name="dZPos"></param>
/// <param name="clColor"></param>
/// <param name="dRadius"></param>
public Sphere AddSphere(double dXPos, double dYPos, double dZPos, double dRadius)
{
if (arrObjects == null)
arrObjects = new ArrayList();
Sphere sphNewSphere = new Sphere(dXPos, dYPos, dZPos, dRadius);
arrObjects.Add(sphNewSphere);
return sphNewSphere;
}