public static bool Intersects(BoundingBox box, BoundingSphere sphere){
// get closet point in cube
Vector3 clamped = Vector3.Clamp (sphere.Center, box.Minimum, box.Maximum);
float dist = (sphere.Center - clamped).Length;
return dist <= sphere.Radius;
}
public static bool Contains(BoundingBox box, Vector3 vector){
if (box.Minimum.X <= vector.X && vector.X <= box.Maximum.X &&
box.Minimum.Y <= vector.Y && vector.Y <= box.Maximum.Y &&
box.Minimum.Z <= vector.Z && vector.Z <= box.Maximum.Z) {
return true;
} else {
return false;
}
}
public static bool Intersects(BoundingBox box1, BoundingBox box2){
if (box1.Minimum.X > box2.Maximum.X || box1.Maximum.X < box2.Minimum.X) {
return false;
}
if (box1.Minimum.Y > box2.Maximum.Y || box1.Maximum.Y < box2.Minimum.Y) {
return false;
}
return (box1.Minimum.Z <= box2.Maximum.Z && box1.Maximum.Z >= box2.Minimum.Z);
}
public static bool Intersect(Plane plane, BoundingBox box){
// source: SlimDX math/Plane.cpp
Vector3 min, max;
max.X = (plane.Normal.X >= 0.0f) ? box.Minimum.X : box.Maximum.X;
max.Y = (plane.Normal.Y >= 0.0f) ? box.Minimum.Y : box.Maximum.Y;
max.Z = (plane.Normal.Z >= 0.0f) ? box.Minimum.Z : box.Maximum.Z;
min.X = (plane.Normal.X >= 0.0f) ? box.Maximum.X : box.Minimum.X;
min.Y = (plane.Normal.Y >= 0.0f) ? box.Maximum.Y : box.Minimum.Y;
min.Z = (plane.Normal.Z >= 0.0f) ? box.Maximum.Z : box.Minimum.Z;
return Distance (plane, max) <= 0.0f && Distance (plane, min) >= 0.0f;
}
public static bool Intersect(Ray ray, BoundingBox box, out float distance){
// current minimum t to get inside
float t = 0.0f;
// max t before going outside in one dim
float tmax = float.MaxValue;
for (int dim = 0; dim < 3; dim++) {
if (Math.Abs (ray.Direction [dim]) < Precission) {
// parallel to X face
if (ray.Position [dim] < box.Minimum [dim] || ray.Position [dim] > box.Maximum [dim]) {
distance = 0.0f;
return false;
}
} else {
// ray eq:
// p = p0 + t * d
// t = (p.x - p0.x)/d.x
float tin = (box.Minimum [dim] - ray.Position [dim]) / ray.Direction [dim];
float tout = (box.Maximum [dim] - ray.Position [dim]) / ray.Direction [dim];
if (tin > tout) {
float aux = tin;
tin = tout;
tout = aux;
}
t = Math.Max (tin, t);
tmax = Math.Min (tout, tmax);
if (t > tmax) {
// is out of another dim when entering this one.
distance = 0.0f;
return false;
}
}
}
distance = t;
return true;
}
public static bool Intersects(BoundingBox box, Ray ray, out float distance){
return Ray.Intersect (ray, box, out distance);
}
public static bool Intersects(BoundingBox box, Plane plane){
return Plane.Intersect (plane, box);
}
public static bool Intersects(BoundingSphere sphere, BoundingBox box){
return BoundingBox.Intersects(box, sphere);
}
public static bool Intersects(BoundingSphere sphere, BoundingBox box)
{
return(BoundingBox.Intersects(box, sphere));
}
