public void RayInterSection_OnSpherePointingIn_OneIntersection()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 2.0);
var ray = new Ray3D(sphere.Center + new Vector3D(0, 0, sphere.Radius), new Vector3D(0.01, 0.09, -0.87));
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result));
Assert.AreEqual(2, result.Length, "Number of intersections should be 1");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[0]), 1e-6, "Point 1 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1 is not on ray.");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[1]), 1e-6, "Point 2 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[1]).DistanceTo(result[1]), 1e-6, "Point 2 is not on ray.");
}
public void RayInterSection_OnSpherePointingIn_OneIntersection()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 2.0);
var ray = new Ray3D(sphere.Center + new Vector3D(0, 0, sphere.Radius), new Vector3D(0.01, 0.09, -0.87));
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result));
Assert.AreEqual(2, result.Length, "Number of intersections should be 1");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[0]), 1e-6, "Point 1 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1 is not on ray.");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[1]), 1e-6, "Point 2 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[1]).DistanceTo(result[1]), 1e-6, "Point 2 is not on ray.");
}
public void RayInterSection_OutsideSpherePointingToCenter_TwoIntersections()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 1.0);
var p = new Point3D(12, 23, 32);
var ray = new Ray3D(p, sphere.Center - p);
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result));
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[0]), 1e-6, "Point 1 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1" + result[0] + " is not on ray.");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[1]), 1e-6, "Point 2 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[1]).DistanceTo(result[1]), 1e-6, "Point 2 " + result[0] + " is not on ray.");
Assert.IsTrue(ray.Origin.DistanceTo(result[0]) < ray.Origin.DistanceTo(result[1]), "The points should be sorted by distance from ray origin.");
}
public void RayInterSection_OutsideSpherePointingToCenter_TwoIntersections()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 1.0);
var p = new Point3D(12, 23, 32);
var ray = new Ray3D(p, sphere.Center - p);
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result));
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[0]), 1e-6, "Point 1 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1" + result[0] + " is not on ray.");
Assert.AreEqual(sphere.Radius, sphere.Center.DistanceTo(result[1]), 1e-6, "Point 2 is not on sphere.");
Assert.AreEqual(0, ray.GetNearest(result[1]).DistanceTo(result[1]), 1e-6, "Point 2 " + result[0] + " is not on ray.");
Assert.IsTrue(ray.Origin.DistanceTo(result[0]) < ray.Origin.DistanceTo(result[1]), "The points should be sorted by distance from ray origin.");
}
public void GetNearest_PointOnRay()
{
var ray = new Ray3D(new Point3D(0, 0, 0), new Vector3D(1, 2, 3));
var p0 = new Point3D(0.1, 0.2, 0.3);
var p = ray.GetNearest(p0);
Assert.AreEqual(0, p0.DistanceTo(p), 1e-12);
}
public void GetNearest_PointOnRay()
{
var ray = new Ray3D(new Point3D(0, 0, 0), new Vector3D(1, 2, 3));
var p0 = new Point3D(0.1, 0.2, 0.3);
var p = ray.GetNearest(p0);
Assert.AreEqual(0, p0.DistanceTo(p), 1e-12);
}
private Point3D?GetNearestPoint(Point position, Point3D hitPlaneOrigin, Vector3D hitPlaneNormal)
{
var hpp = this.GetHitPlanePoint(position, hitPlaneOrigin, hitPlaneNormal);
if (hpp == null)
{
return(null);
}
var ray = new Ray3D(this.ToWorld(this.Position), this.ToWorld(this.Direction));
return(ray.GetNearest(hpp.Value));
}
public void RayInterSection_OutsideAndTangentToSphere_OneIntersection()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 1.0);
var p = new Point3D(sphere.Center.X + sphere.Radius, sphere.Center.Y + sphere.Radius, sphere.Center.Z + 50);
var p2 = new Point3D(sphere.Center.X + sphere.Radius, sphere.Center.Y, sphere.Center.Z);
// ray tangent to sphere
var ray = new Ray3D(p, p2 - p);
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result), "No intersection");
Assert.AreEqual(1, result.Length, "One intersection");
Assert.AreEqual(sphere.Radius, result[0].DistanceTo(sphere.Center), 1e-8);
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1 is not on ray.");
}
public void RayInterSection_OutsideAndTangentToSphere_OneIntersection()
{
var sphere = new BoundingSphere(new Point3D(0.2, 0.3, 0), 1.0);
var p = new Point3D(sphere.Center.X + sphere.Radius, sphere.Center.Y + sphere.Radius, sphere.Center.Z + 50);
var p2 = new Point3D(sphere.Center.X + sphere.Radius, sphere.Center.Y, sphere.Center.Z);
// ray tangent to sphere
var ray = new Ray3D(p, p2 - p);
Point3D[] result;
Assert.IsTrue(sphere.RayIntersection(ray, out result), "No intersection");
Assert.AreEqual(1, result.Length, "One intersection");
Assert.AreEqual(sphere.Radius, result[0].DistanceTo(sphere.Center), 1e-8);
Assert.AreEqual(0, ray.GetNearest(result[0]).DistanceTo(result[0]), 1e-6, "Point 1 is not on ray.");
}
/// <summary>
/// Gets the nearest point on the translation axis.
/// </summary>
/// <param name="position">
/// The position (in screen coordinates).
/// </param>
/// <param name="hitPlaneOrigin">
/// The hit plane origin (world coordinate system).
/// </param>
/// <param name="hitPlaneNormal">
/// The hit plane normal (world coordinate system).
/// </param>
/// <returns>
/// The nearest point (world coordinates) or null if no point could be found.
/// </returns>
private Point3D? GetNearestPoint(Point position, Point3D hitPlaneOrigin, Vector3D hitPlaneNormal)
{
var hpp = this.GetHitPlanePoint(position, hitPlaneOrigin, hitPlaneNormal);
if (hpp == null)
{
return null;
}
var ray = new Ray3D(this.ToWorld(this.Position), this.ToWorld(this.Direction));
return ray.GetNearest(hpp.Value);
}