public static void Normalize(this SCNVector3 vector3)
{
var normalizedVector = vector3.Normalized();
vector3.X = normalizedVector.X;
vector3.Y = normalizedVector.Y;
vector3.Z = normalizedVector.Z;
}
public SCNVector3?IntersectionWithHorizontalPlane(float planeY)
{
SCNVector3 rayOrigin = Origin;
SCNVector3 direction = Direction;
// Normalize direction
direction = direction.Normalized();
// Special case handling: Check if the ray is horizontal as well.
if (direction.Y == 0)
{
if (rayOrigin.Y == planeY)
{
// The ray is horizontal and on the plane, thus all points on the ray intersect with the plane.
// Therefore we simply return the ray origin.
return(rayOrigin);
}
else
{
// The ray is parallel to the plane and never intersects.
return(null);
}
}
// The distance from the ray's origin to the intersection point on the plane is:
// (pointOnPlane - rayOrigin) dot planeNormal
// --------------------------------------------
// direction dot planeNormal
// Since we know that horizontal planes have normal (0, 1, 0), we can simplify this to:
var dist = (planeY - rayOrigin.Y) / direction.Y;
// Do not return intersections behind the ray's origin.
if (dist < 0)
{
return(null);
}
// Return the intersection point.
return(rayOrigin.Add(direction * dist));
}