public int getMaterialIndex(Material material)
{
Debug.Assert(material.Reflectivity >= 0 && material.Reflectivity <= 1.0f);
Debug.Assert(material.Transparency >= 0 && material.Transparency <= 1.0f);
int materialIndex = _nextOpening;
for (int i=0; i< _nextOpening; i++)
{
Material mat = _materialArray[i];
if (mat == material)
{
materialIndex = i;
break;
}
}
System.Diagnostics.Debug.Assert(materialIndex < _materialArray.Length, "Maxium number of materials exceeded.");
if (materialIndex == _nextOpening)
{
_materialArray[materialIndex] = material;
_nextOpening++;
}
return materialIndex;
}
public virtual float getNearestIntersection(ref Ray r, ref Vector3 collisionPoint, ref Vector3 surfaceNormal, ref Material mat)
{
float nearestIntersection = float.PositiveInfinity;
foreach (Sphere s in _spheres)
{
float intersection = r.intersects(s, ref collisionPoint, ref surfaceNormal);
if (intersection < nearestIntersection)
{
nearestIntersection = intersection;
mat = s.Material;
}
}
return nearestIntersection;
}
public override float getNearestIntersection(ref Ray ray, ref Vector3 collisionPoint, ref Vector3 surfaceNormal, ref Material mat)
{
// Use KD-Tree to check for intersection
Sphere primHit;
float t = _tree.getNearestIntersection(ref ray, out primHit);
if ( !float.IsPositiveInfinity(t) )
{
ray.Direction.Normalize();
collisionPoint = ray.Origin + (Vector3)(t * ray.Direction);
surfaceNormal = Vector3.Subtract(collisionPoint, primHit.Position);
surfaceNormal.Normalize();
collisionPoint = primHit.Position + primHit.Radius * surfaceNormal;
mat = primHit.Material;
}
return t;
}