public void AssertThat_Inflate_IncreasesSize()
{
BoundingBox s = new BoundingBox(new Vector3(0), new Vector3(10));
Assert.AreEqual(new Vector3(-5), s.Inflate(10).Min);
Assert.AreEqual(new Vector3(15), s.Inflate(10).Max);
}
public void AssertThat_Inflate_ByNegativeValue_DecreasesSize()
{
BoundingBox s = new BoundingBox(new Vector3(0), new Vector3(10));
Assert.AreEqual(new Vector3(3), s.Inflate(-6).Min);
Assert.AreEqual(new Vector3(7), s.Inflate(-6).Max);
}
/// <summary>
/// Creates the smallest BoundingSphere that can contain a specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to create the BoundingSphere from.</param><param name="result">[OutAttribute] The created BoundingSphere.</param>
public static void CreateFromBoundingBox(ref BoundingBox box, out BoundingSphere result)
{
// Find the center of the box.
Vector3 center = new Vector3((box.Min.X + box.Max.X) / 2.0f,
(box.Min.Y + box.Max.Y) / 2.0f,
(box.Min.Z + box.Max.Z) / 2.0f);
// Find the distance between the center and one of the corners of the box.
float radius = Vector3.Distance(center, box.Max);
result = new BoundingSphere(center, radius);
}
private BoundingRectangle CalculateScreenSpaceBounds(IGeometry item, View view)
{
//Create a bounding box around this geometry
var box = new BoundingBox(item.BoundingSphere);
box.GetCorners(_corners);
//Multiply box corners by WVP matrix to move into screen space
for (int i = 0; i < _corners.Length; i++)
{
//Why is world matrix Identity?
//THe bounding sphere is already in world space, we don't need to apply it again!
_corners[i] = view.Viewport.Project(_corners[i].ToXNA(), view.Camera.Projection.ToXNA(), view.Camera.View.ToXNA(), Microsoft.Xna.Framework.Matrix.Identity).FromXNA();
_corners2D[i] = _corners[i].XY();
}
//Find a rectangle around this box
var rect = BoundingRectangle.CreateFromPoints(_corners2D);
return rect;
}
internal Node(Octree octree, Node parent, BoundingBox bounds)
{
Octree = octree;
Parent = parent;
Bounds = bounds;
}
private BoundingRectangle CalculateScreenSpaceBounds(IGeometry item, View view)
{
//Create a bounding box around this geometry
var box = new BoundingBox(item.BoundingSphere);
var corners = box.GetCorners();
//Multiply box corners by WVP matrix to move into screen space
for (int i = 0; i < corners.Length; i++)
{
corners[i] = view.Viewport.Project(corners[i].ToXNA(), view.Camera.Projection.ToXNA(), view.Camera.View.ToXNA(), Matrix.Identity).FromXNA();
}
//Find a rectangle around this box
var rect = BoundingRectangle.CreateFromPoints(corners.Select(a => a.XY()));
return rect;
}
public void AssertThat_InflateSphere_ByNegativeValueLargerThanSize_Throws()
{
BoundingBox s = new BoundingBox(Vector3.Zero, new Vector3(10));
var result = s.Inflate(-50);
}
/// <summary>
/// Checks whether the current Ray intersects a BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with.</param><param name="result">[OutAttribute] Distance at which the ray intersects the BoundingBox or null if there is no intersection.</param>
public void Intersects(ref BoundingBox box, out float? result)
{
const float EPSILON = 1e-6f;
float? tMin = null, tMax = null;
if (Math.Abs(Direction.X) < EPSILON)
{
if (Position.X < box.Min.X || Position.X > box.Max.X)
{
result = null;
return;
}
}
else
{
tMin = (box.Min.X - Position.X) / Direction.X;
tMax = (box.Max.X - Position.X) / Direction.X;
if (tMin > tMax)
{
var temp = tMin;
tMin = tMax;
tMax = temp;
}
}
if (Math.Abs(Direction.Y) < EPSILON)
{
if (Position.Y < box.Min.Y || Position.Y > box.Max.Y)
{
result = null;
return;
}
}
else
{
var tMinY = (box.Min.Y - Position.Y) / Direction.Y;
var tMaxY = (box.Max.Y - Position.Y) / Direction.Y;
if (tMinY > tMaxY)
{
var temp = tMinY;
tMinY = tMaxY;
tMaxY = temp;
}
if ((tMin.HasValue && tMin > tMaxY) || (tMax.HasValue && tMinY > tMax))
{
result = null;
return;
}
if (!tMin.HasValue || tMinY > tMin) tMin = tMinY;
if (!tMax.HasValue || tMaxY < tMax) tMax = tMaxY;
}
if (Math.Abs(Direction.Z) < EPSILON)
{
if (Position.Z < box.Min.Z || Position.Z > box.Max.Z)
{
result = null;
return;
}
}
else
{
var tMinZ = (box.Min.Z - Position.Z) / Direction.Z;
var tMaxZ = (box.Max.Z - Position.Z) / Direction.Z;
if (tMinZ > tMaxZ)
{
var temp = tMinZ;
tMinZ = tMaxZ;
tMaxZ = temp;
}
if ((tMin.HasValue && tMin > tMaxZ) || (tMax.HasValue && tMinZ > tMax))
{
result = null;
return;
}
if (!tMin.HasValue || tMinZ > tMin) tMin = tMinZ;
if (!tMax.HasValue || tMaxZ < tMax) tMax = tMaxZ;
}
// having a positive tMin and a negative tMax means the ray is inside the box
// we expect the intesection distance to be 0 in that case
if ((tMin.HasValue && tMin < 0) && tMax > 0)
{
result = 0;
return;
}
// a negative tMin means that the intersection point is behind the ray's origin
// we discard these as not hitting the AABB
if (tMin < 0)
{
result = null;
return;
}
result = tMin;
}
public static void AddBoundingBox(BoundingBox box, Color color, float life = 0f)
{
// Get a DebugShape we can use to draw the box
DebugShape shape = GetShapeForLines(12, life);
// Get the corners of the box
box.GetCorners(_corners);
// Fill in the vertices for the bottom of the box
shape.Vertices[0] = new VertexPositionColor(_corners[0].ToXNA(), color);
shape.Vertices[1] = new VertexPositionColor(_corners[1].ToXNA(), color);
shape.Vertices[2] = new VertexPositionColor(_corners[1].ToXNA(), color);
shape.Vertices[3] = new VertexPositionColor(_corners[2].ToXNA(), color);
shape.Vertices[4] = new VertexPositionColor(_corners[2].ToXNA(), color);
shape.Vertices[5] = new VertexPositionColor(_corners[3].ToXNA(), color);
shape.Vertices[6] = new VertexPositionColor(_corners[3].ToXNA(), color);
shape.Vertices[7] = new VertexPositionColor(_corners[0].ToXNA(), color);
// Fill in the vertices for the top of the box
shape.Vertices[8] = new VertexPositionColor(_corners[4].ToXNA(), color);
shape.Vertices[9] = new VertexPositionColor(_corners[5].ToXNA(), color);
shape.Vertices[10] = new VertexPositionColor(_corners[5].ToXNA(), color);
shape.Vertices[11] = new VertexPositionColor(_corners[6].ToXNA(), color);
shape.Vertices[12] = new VertexPositionColor(_corners[6].ToXNA(), color);
shape.Vertices[13] = new VertexPositionColor(_corners[7].ToXNA(), color);
shape.Vertices[14] = new VertexPositionColor(_corners[7].ToXNA(), color);
shape.Vertices[15] = new VertexPositionColor(_corners[4].ToXNA(), color);
// Fill in the vertices for the vertical sides of the box
shape.Vertices[16] = new VertexPositionColor(_corners[0].ToXNA(), color);
shape.Vertices[17] = new VertexPositionColor(_corners[4].ToXNA(), color);
shape.Vertices[18] = new VertexPositionColor(_corners[1].ToXNA(), color);
shape.Vertices[19] = new VertexPositionColor(_corners[5].ToXNA(), color);
shape.Vertices[20] = new VertexPositionColor(_corners[2].ToXNA(), color);
shape.Vertices[21] = new VertexPositionColor(_corners[6].ToXNA(), color);
shape.Vertices[22] = new VertexPositionColor(_corners[3].ToXNA(), color);
shape.Vertices[23] = new VertexPositionColor(_corners[7].ToXNA(), color);
}
/// <summary>
/// Tests whether the BoundingBox contains a BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to test for overlap.</param><param name="result">[OutAttribute] Enumeration indicating the extent of overlap.</param>
public void Contains(ref BoundingBox box, out ContainmentType result)
{
//test if all corner is in the same side of a face by just checking min and max
if (box.Max.X < Min.X
|| box.Min.X > Max.X
|| box.Max.Y < Min.Y
|| box.Min.Y > Max.Y
|| box.Max.Z < Min.Z
|| box.Min.Z > Max.Z)
{
result = ContainmentType.Disjoint;
return;
}
if (box.Min.X >= Min.X
&& box.Max.X <= Max.X
&& box.Min.Y >= Min.Y
&& box.Max.Y <= Max.Y
&& box.Min.Z >= Min.Z
&& box.Max.Z <= Max.Z)
{
result = ContainmentType.Contains;
return;
}
result = ContainmentType.Intersects;
}
public bool Intersects(BoundingBox box)
{
bool result;
Intersects(ref box, out result);
return result;
}
/// <summary>
/// Creates the smallest BoundingBox that contains the two specified BoundingBox instances.
/// </summary>
/// <param name="original">One of the BoundingBoxs to contain.</param><param name="additional">One of the BoundingBoxs to contain.</param>
public static BoundingBox CreateMerged(BoundingBox original, BoundingBox additional)
{
BoundingBox result;
CreateMerged(ref original, ref additional, out result);
return result;
}
/// <summary>
/// Expand bounding box by distance / 2 at min and max (total of distance)
/// </summary>
/// <param name="box">The box to mutate</param>
/// <param name="distance"></param>
/// <returns></returns>
public static void Inflate(ref BoundingBox box, float distance)
{
var min = box.Min - new Vector3(distance / 2);
var max = box.Max + new Vector3(distance / 2);
if (distance < 0)
{
if (Vector3.Min(min, max) != min)
throw new ArgumentOutOfRangeException("distance", "Distance specified to inflate rectangle is a negative value larger than the total diagonal size of the rectangle (doing this would invert the rectangle!");
}
box.Min = min;
box.Max = max;
}
/// <summary>
/// Checks whether the current BoundingFrustum intersects a BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with.</param><param name="result">[OutAttribute] true if the BoundingFrustum and BoundingBox intersect; false otherwise.</param>
public void Intersects(ref BoundingBox box, out bool result)
{
ContainmentType containment;
Contains(ref box, out containment);
result = containment != ContainmentType.Disjoint;
}
/// <summary>
/// Checks whether the current BoundingSphere contains the specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to test for overlap.</param><param name="result">[OutAttribute] Enumeration indicating the extent of overlap.</param>
public void Contains(ref BoundingBox box, out ContainmentType result)
{
//check if all corner is in sphere
bool inside = true;
foreach (Vector3 corner in box.GetCorners())
{
if (Contains(corner) == ContainmentType.Disjoint)
{
inside = false;
break;
}
}
if (inside)
{
result = ContainmentType.Contains;
return;
}
//check if the distance from sphere center to cube face < radius
double dmin = 0;
if (Center.X < box.Min.X)
dmin += (Center.X - box.Min.X) * (Center.X - box.Min.X);
else if (Center.X > box.Max.X)
dmin += (Center.X - box.Max.X) * (Center.X - box.Max.X);
if (Center.Y < box.Min.Y)
dmin += (Center.Y - box.Min.Y) * (Center.Y - box.Min.Y);
else if (Center.Y > box.Max.Y)
dmin += (Center.Y - box.Max.Y) * (Center.Y - box.Max.Y);
if (Center.Z < box.Min.Z)
dmin += (Center.Z - box.Min.Z) * (Center.Z - box.Min.Z);
else if (Center.Z > box.Max.Z)
dmin += (Center.Z - box.Max.Z) * (Center.Z - box.Max.Z);
if (dmin <= Radius * Radius)
{
result = ContainmentType.Intersects;
return;
}
//else disjoint
result = ContainmentType.Disjoint;
}
/// <summary>
/// Checks whether the current BoundingFrustum contains the specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to test for overlap.</param><param name="result">[OutAttribute] Enumeration indicating the extent of overlap.</param>
public void Contains(ref BoundingBox box, out ContainmentType result)
{
CreatePlanes();
var intersects = false;
for (var i = 0; i < PlaneCount; ++i)
{
PlaneIntersectionType planeIntersectionType;
box.Intersects(ref _planes[i], out planeIntersectionType);
switch (planeIntersectionType)
{
case PlaneIntersectionType.Front:
result = ContainmentType.Disjoint;
return;
case PlaneIntersectionType.Intersecting:
intersects = true;
break;
}
}
result = intersects ? ContainmentType.Intersects : ContainmentType.Contains;
}
private void Update()
{
_axisAligned = _bounds.Transform(ref _transform);
_dirty = false;
}
/// <summary>
/// Checks whether the current BoundingSphere intersects with a specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with the current BoundingSphere.</param>
public bool Intersects(BoundingBox box)
{
return box.Intersects(this);
}
/// <summary>
/// Creates the smallest BoundingSphere that can contain a specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to create the BoundingSphere from.</param>
public static BoundingSphere CreateFromBoundingBox(BoundingBox box)
{
BoundingSphere result;
CreateFromBoundingBox(ref box, out result);
return result;
}
/// <summary>
/// Checks whether the current BoundingSphere intersects a BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with.</param><param name="result">[OutAttribute] true if the BoundingSphere and BoundingBox intersect; false otherwise.</param>
public void Intersects(ref BoundingBox box, out bool result)
{
result = box.Intersects(this);
}
/// <summary>
/// Creates the smallest BoundingBox that will contain the specified BoundingSphere.
/// </summary>
/// <param name="sphere">The BoundingSphere to contain.</param><param name="result">[OutAttribute] The created BoundingBox.</param>
public static void CreateFromSphere(ref BoundingSphere sphere, out BoundingBox result)
{
var corner = new Vector3(sphere.Radius);
result.Min = sphere.Center - corner;
result.Max = sphere.Center + corner;
}
/// <summary>
/// Fetches all nodes (including non leaf nodes) which intersect the given bounds
/// </summary>
/// <param name="bounds"></param>
/// <returns></returns>
public IEnumerable<Node> NodesOverlappingBounds(BoundingBox bounds)
{
if (!bounds.Intersects(Bounds))
yield break;
yield return this;
if (_children != null)
foreach (var descendant in _children.SelectMany(c => c.NodesOverlappingBounds(bounds)))
yield return descendant;
}
/// <summary>
/// Creates the smallest BoundingBox that contains the two specified BoundingBox instances.
/// </summary>
/// <param name="original">One of the BoundingBox instances to contain.</param><param name="additional">One of the BoundingBox instances to contain.</param><param name="result">[OutAttribute] The created BoundingBox.</param>
public static void CreateMerged(ref BoundingBox original, ref BoundingBox additional, out BoundingBox result)
{
result = new BoundingBox(
Vector3.Min(original.Min, additional.Min),
Vector3.Max(original.Max, additional.Max)
);
}
/// <summary>
/// Construct a new octree with a single root node covering the given bounds
/// </summary>
/// <param name="bounds"></param>
/// <param name="childFactory"></param>
public Octree(BoundingBox bounds, Func<Octree, Node, BoundingBox, Node> childFactory)
{
_childFactory = childFactory;
Root = _childFactory(this, null, bounds);
}
public ContainmentType Contains(BoundingBox box)
{
ContainmentType result;
Contains(ref box, out result);
return result;
}
/// <summary>
/// Get all nodes overlapping the bounds
/// </summary>
/// <param name="bounds"></param>
/// <returns></returns>
public IEnumerable<Node> NodesOverlappingBounds(BoundingBox bounds)
{
return Root.NodesOverlappingBounds(bounds);
}
public bool Equals(BoundingBox other)
{
return Min.Equals(other.Min) && Max.Equals(other.Max);
}
private Node CreateChild(Node parent, BoundingBox bounds)
{
return _childFactory(this, parent, bounds);
}
/// <summary>
/// Checks whether the current BoundingBox intersects another BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with.</param><param name="result">[OutAttribute] true if the BoundingBox instances intersect; false otherwise.</param>
public void Intersects(ref BoundingBox box, out bool result)
{
result = box.Min.X < Max.X && box.Max.X > Min.X
&& box.Min.Y < Max.Y && box.Max.Y > Min.Y
&& box.Min.Z < Max.Z && box.Max.Z > Min.Z;
}
//public float DistanceToPoint(Vector3 point)
//{
//}
//public void DistanceToPoint(ref Vector3 point, out float distance)
//{
//float result;
//DistanceToPoint(ref point, out result);
//return result;
//}
//public RayRayIntersection? Intersects(Ray3 ray, out Parallelism parallelism)
//{
//}
//public RayRayIntersection? Intersects(Ray3 ray)
//{
//}
//public struct RayRayIntersection
//{
// /// <summary>
// /// The position where the two rays intersect
// /// </summary>
// public readonly Vector3 Position;
// /// <summary>
// /// The distance along ray A. Units are in ray lengths, so 0 indicates the start, 1 indicates the end.
// /// </summary>
// public readonly float DistanceAlongA;
// /// <summary>
// /// The distance along ray B. Units are in ray lengths, so 0 indicates the start, 1 indicates the end.
// /// </summary>
// public readonly float DistanceAlongB;
// public RayRayIntersection(Vector3 position, float distanceAlongLineA, float distanceAlongLineB)
// {
// Position = position;
// DistanceAlongA = distanceAlongLineA;
// DistanceAlongB = distanceAlongLineB;
// }
//}
/// <summary>
/// Checks whether the Ray intersects a specified BoundingBox.
/// </summary>
/// <param name="box">The BoundingBox to check for intersection with the Ray.</param>
public float? Intersects(BoundingBox box)
{
float? result;
Intersects(ref box, out result);
return result;
}
