/// <summary>
/// Given an Intersection and a Ray
/// evaluates for eye vector, normal vector, insection point,
/// and if ray is inside of object.
/// This is the same as calling the Computation class constructor with Intersection and Ray parameter
/// </summary>
/// <param name="i"></param>
/// <param name="r"></param>
public static Computation PrepareComputations(Intersection i, Ray r, List <Intersection> xs = null)
{
Computation comp = new Computation();
comp.t = i.t;
comp.rayObject = i.rayObject;
comp.point = r.GetPointPosition(i.t);
comp.eyeV = -r.direction;
comp.normalV = comp.rayObject.GetNormal(comp.point);
// Checks if eye vector and normal are pointing in the same direction
// if dot product is less than zero that point in the same direction
if (Vector3.Dot(comp.eyeV, comp.normalV) < 0)
{
comp.inside = true;
comp.normalV = -comp.normalV;
}
else
{
comp.inside = false;
}
if (xs == null)
{
xs = new List <Intersection>()
{
i
}
}
;
// Transparency Intersections algorithm
List <RayObject> containers = new List <RayObject>();
foreach (Intersection intersect in xs)
{
// n1
if (i == intersect)
{
if (containers.Count == 0)
{
comp.n1 = 1.0f;
}
else
{
comp.n1 = containers.Last <RayObject>().material.RefractIndex;
}
}
if (containers.Contains(intersect.rayObject))
{
containers.Remove(intersect.rayObject);
//Console.WriteLine("Object Removed: " + intersect.rayObject.ToString());
}
else
{
containers.Add(intersect.rayObject);
//Console.WriteLine("Object Added: " + intersect.rayObject.ToString());
}
//Console.WriteLine("List Lenght: " + containers.Count);
// n2
if (i == intersect)
{
if (containers.Count == 0)
{
comp.n2 = 1.0f;
}
else
{
comp.n2 = containers[containers.Count - 1].material.RefractIndex;
}
break;
}
}
comp.reflectV = Vector3.Reflection(r.direction, comp.normalV);
comp.overPoint = comp.point + comp.normalV * Utilities.OVER_POINT_EPSILON;
comp.underPoint = comp.point - comp.normalV * Utilities.UNDER_POINT_EPSILON;
return(comp);
}
}
//public Computation(float t, RayObject rayObject,
// Point point, Vector3 eyeV,
// Vector3 normalV, bool inside,
// Vector3 reflectV, float n1,
// float n2)
//{
// this.t = t;
// this.rayObject = rayObject;
// this.point = point;
// this.eyeV = eyeV;
// this.normalV = normalV;
// this.inside = inside;
// overPoint = point + normalV * Utilities.shadowPointEpsilon;
// this.reflectV = reflectV;
// this.n1 = n1;
// this.n2 = n2;
//}
public Computation(Intersection i, Ray r, List <Intersection> xs = null)
{
this.t = i.t;
this.rayObject = i.rayObject;
this.point = r.GetPointPosition(i.t);
this.eyeV = -r.direction;
this.normalV = rayObject.GetNormal(point);
// Checks if eye vector and normal are pointing in the same direction
// if dot product is less than zero that point in the same direction.
if (Vector3.Dot(eyeV, normalV) < 0)
{
inside = true;
normalV = -normalV;
}
else
{
inside = false;
}
// If a List<Intersection> parameter is not passed into the method
// create one using i as the only intersection in the list
if (xs == null)
{
xs = new List <Intersection>()
{
i
}
}
;
// Transparency Intersections algorithm
List <RayObject> containers = new List <RayObject>();
foreach (Intersection intersect in xs)
{
// n1
if (i == intersect)
{
if (containers.Count == 0)
{
this.n1 = 1.0f;
}
else
{
this.n1 = containers.Last <RayObject>().material.RefractIndex;
}
}
if (containers.Contains(intersect.rayObject))
{
containers.Remove(intersect.rayObject);
//Console.WriteLine("Object Removed: " + intersect.rayObject.ToString());
}
else
{
containers.Add(intersect.rayObject);
//Console.WriteLine("Object Added: " + intersect.rayObject.ToString());
}
//Console.WriteLine("List Lenght: " + containers.Count);
// n2
if (i == intersect)
{
if (containers.Count == 0)
{
this.n2 = 1.0f;
}
else
{
this.n2 = containers[containers.Count - 1].material.RefractIndex;
}
break;
}
}
this.reflectV = Vector3.Reflection(r.direction, this.normalV);
this.overPoint = point + normalV * Utilities.OVER_POINT_EPSILON;
this.underPoint = point - normalV * Utilities.UNDER_POINT_EPSILON;
}
