/**
* Refraction
*
* @param incoming incoming vector
* @param normal normal of the reflectio area
* @param outgoing result of the computation
*/
public static Vect3 RefractOn(this Vect3 incoming, Vect3 normal, double refractionIndex)
{
//test implementation - working but propably slow
Vect3 result = incoming.ProjectOnNormal(normal);
result = result / refractionIndex;
double quadLen = result.QuadLength();
if (quadLen >= 1) //total reflection
{
result = incoming.ReflectOn(normal);
}
else
{
result = result + (normal * -System.Math.Sqrt(1 - quadLen));
result = result.Normalize();
}
return(result);
}