public override IntersectionList LocalIntersect(Ray ray)
{
var intersections = new IntersectionList();
//var shapeToRay = ray.Origin - new RtPoint(0, 0, 0);
var shapeToRay = ray.Origin.DistanceFromZero();
var a = ray.Direction.Dot(ray.Direction);
var b = 2 * ray.Direction.Dot(shapeToRay);
var c = shapeToRay.Dot(shapeToRay) - 1;
var discriminant = Math.Pow(b, 2) - 4 * a * c;
if (discriminant < 0)
{
return(intersections);
}
var t1 = (-b - Math.Sqrt(discriminant)) / (2 * a);
var t2 = (-b + Math.Sqrt(discriminant)) / (2 * a);
intersections.Add(new Intersection(t1, this));
intersections.Add(new Intersection(t2, this));
return(intersections);
}
public override IntersectionList LocalIntersect(Ray ray)
{
var intersections = new IntersectionList();
var a = Math.Pow(ray.Direction.X, 2) - Math.Pow(ray.Direction.Y, 2) + Math.Pow(ray.Direction.Z, 2);
var b = 2 * ray.Origin.X * ray.Direction.X - 2 * ray.Origin.Y * ray.Direction.Y + 2 * ray.Origin.Z * ray.Direction.Z;
if (a.ApproximateEquals(0) && b.ApproximateEquals(0))
{
IntersectCaps(ray, intersections);
return(intersections);
}
var c = Math.Pow(ray.Origin.X, 2) - Math.Pow(ray.Origin.Y, 2) + Math.Pow(ray.Origin.Z, 2);
if (a == 0 && b != 0)
{
var time = -c / (2 * b);
intersections.Add(time, this);
IntersectCaps(ray, intersections);
return(intersections);
}
var discriminant = Math.Pow(b, 2) - 4 * a * c;
var t0 = (-b - Math.Sqrt(discriminant)) / (2 * a);
var t1 = (-b + Math.Sqrt(discriminant)) / (2 * a);
if (t0 > t1)
{
var tt = t0;
t0 = t1;
t1 = tt;
}
var y0 = ray.Origin.Y + t0 * ray.Direction.Y;
if (Minimum < y0 && y0 < Maximum)
{
intersections.Add(t0, this);
}
var y1 = ray.Origin.Y + t1 * ray.Direction.Y;
if (Minimum < y1 && y1 < Maximum)
{
intersections.Add(t1, this);
}
IntersectCaps(ray, intersections);
return(intersections);
}
public override IntersectionList LocalIntersect(Ray ray)
{
var intersections = new IntersectionList();
if (!CheckAxis(ray, out double tmin, out double tmax))
{
return(intersections);
}
intersections.Add(tmin, this);
intersections.Add(tmax, this);
return(intersections);
}
private void IntersectCaps(Ray ray, IntersectionList intersections)
{
if (!IsClosed || ray.Direction.Y < 0)
{
return;
}
var time = (Minimum - ray.Origin.Y) / ray.Direction.Y;
if (CheckCap(ray, Minimum, time))
{
intersections.Add(time, this);
}
time = (Maximum - ray.Origin.Y) / ray.Direction.Y;
if (CheckCap(ray, Maximum, time))
{
intersections.Add(time, this);
}
}
public override IntersectionList LocalIntersect(Ray ray)
{
var intersecitons = new IntersectionList();
if (Math.Abs(ray.Direction.Y) < DoubleExtensions.EPSILON)
{
return(intersecitons);
}
var time = -ray.Origin.Y / ray.Direction.Y;
intersecitons.Add(new Intersection(time, this));
return(intersecitons);
}
public override IntersectionList LocalIntersect(Ray ray)
{
var intersections = new IntersectionList();
var directionCrossEdge2 = ray.Direction.Cross(Edge2);
var determinant = Edge1.Dot(directionCrossEdge2);
if (Math.Abs(determinant) < DoubleExtensions.EPSILON)
{
return(intersections);
}
var f = 1.0 / determinant;
var point1ToOrigin = ray.Origin - Point1;
var u = f * point1ToOrigin.Dot(directionCrossEdge2);
if (u < 0 || u > 1)
{
return(intersections);
}
var originCrossEdge1 = point1ToOrigin.Cross(Edge1);
var v = f * ray.Direction.Dot(originCrossEdge1);
if (v < 0 || (u + v) > 1)
{
return(intersections);
}
var t = f * Edge2.Dot(originCrossEdge1);
var intersection = new Intersection
{
Shape = this,
Time = t,
U = u,
V = v
};
intersections.Add(intersection);
return(intersections);
}
private void IntersectTrianle(TriangleGeometry triangleGeometry, IntersectionList intersections, Ray ray)
{
var vertex1 = _vertices[triangleGeometry.Vertex1 - 1];
var vertex2 = _vertices[triangleGeometry.Vertex2 - 1];
var vertex3 = _vertices[triangleGeometry.Vertex3 - 1];
var edge1 = vertex2 - vertex1;
var edge2 = vertex3 - vertex1;
var directionCrossEdge2 = ray.Direction.Cross(edge2);
var determinant = edge1.Dot(directionCrossEdge2);
if (Math.Abs(determinant) < DoubleExtensions.EPSILON)
{
return;
}
var f = 1.0 / determinant;
var point1ToOrigin = ray.Origin - vertex1;
var u = f * point1ToOrigin.Dot(directionCrossEdge2);
if (u < 0 || u > 1)
{
return;
}
var originCrossEdge1 = point1ToOrigin.Cross(edge1);
var v = f * ray.Direction.Dot(originCrossEdge1);
if (v < 0 || (u + v) > 1)
{
return;
}
var t = f * edge2.Dot(originCrossEdge1);
Triangle triangle;
if (_normals.Count > 0)
{
var normal1 = _normals[triangleGeometry.Normal1 - 1];
var normal2 = _normals[triangleGeometry.Normal2 - 1];
var normal3 = _normals[triangleGeometry.Normal3 - 1];
triangle = new Triangle(vertex1, vertex2, vertex3, normal1, normal2, normal3);
}
else
{
triangle = new Triangle(vertex1, vertex2, vertex3);
}
triangle.Parent = this;
triangle.InheritMaterial = true;
var intersection = new Intersection
{
Shape = triangle,
Time = t,
U = u,
V = v
};
intersections.Add(intersection);
}