public boolean intersectsBoundingBox(BoundingBox bb) {
assert Vector3f.isValidVector(center) && Vector3f.isValidVector(bb.center);
if (FastMath.abs(bb.center.x - center.x) < getRadius() + bb.xExtent
&& FastMath.abs(bb.center.y - center.y) < getRadius() + bb.yExtent
&& FastMath.abs(bb.center.z - center.z) < getRadius() + bb.zExtent) {
return true;
}
return false;
}
/*
* (non-Javadoc)
* @see com.jme.bounding.BoundingVolume#intersectsWhere(com.jme.math.Ray)
*/
public int collideWithRay(Ray ray, CollisionResults results) {
Vector3f vect1 = Vector3f.newInstance();
Vector3f diff = vect1.set(ray.getOrigin()).subtractLocal(center);
float a = diff.dot(diff) - (getRadius() * getRadius());
float a1, discr, root;
if (a <= 0.0) {
// inside sphere
a1 = ray.direction.dot(diff);
discr = (a1 * a1) - a;
root = FastMath.sqrt(discr);
float distance = root - a1;
Vector3f point = new Vector3f(ray.direction).multLocal(distance).addLocal(ray.origin);
CollisionResult result = new CollisionResult(point, distance);
results.addCollision(result);
Vector3f.recycle(vect1);
return 1;
}
a1 = ray.direction.dot(diff);
if (a1 >= 0.0) {
Vector3f.recycle(vect1);
return 0;
}
discr = a1 * a1 - a;
if (discr < 0.0) {
Vector3f.recycle(vect1);
return 0;
} else if (discr >= FastMath.ZERO_TOLERANCE) {
root = FastMath.sqrt(discr);
float dist = -a1 - root;
Vector3f point = new Vector3f(ray.direction).multLocal(dist).addLocal(ray.origin);
results.addCollision(new CollisionResult(point, dist));
dist = -a1 + root;
point = new Vector3f(ray.direction).multLocal(dist).addLocal(ray.origin);
results.addCollision(new CollisionResult(point, dist));
Vector3f.recycle(vect1);
return 2;
} else {
float dist = -a1;
Vector3f point = new Vector3f(ray.direction).multLocal(dist).addLocal(ray.origin);
results.addCollision(new CollisionResult(point, dist));
Vector3f.recycle(vect1);
return 1;
}
}
private float getMaxAxis(Vector3f scale) {
float x = FastMath.abs(scale.x);
float y = FastMath.abs(scale.y);
float z = FastMath.abs(scale.z);
if (x >= y) {
if (x >= z) {
return x;
}
return z;
}
if (y >= z) {
return y;
}
return z;
}
/**
* Calculates the minimum bounding sphere of 2 points. Used in welzl's algorithm.
*
* @param O The 1st point inside the sphere.
* @param A The 2nd point inside the sphere.
* @see #calcWelzl(java.nio.FloatBuffer)
*/
private void setSphere(Vector3f O, Vector3f A) {
radius =
FastMath.sqrt(
((A.x - O.x) * (A.x - O.x) + (A.y - O.y) * (A.y - O.y) + (A.z - O.z) * (A.z - O.z))
/ 4f)
+ RADIUS_EPSILON
- 1f;
center.interpolate(O, A, .5f);
}
public BoundingVolume transform(Matrix4f trans, BoundingVolume store) {
BoundingSphere sphere;
if (store == null || store.getType() != BoundingVolume.Type.Sphere) {
sphere = new BoundingSphere(1, new Vector3f(0, 0, 0));
} else {
sphere = (BoundingSphere) store;
}
trans.mult(center, sphere.center);
Vector3f axes = new Vector3f(1, 1, 1);
trans.mult(axes, axes);
float ax = getMaxAxis(axes);
sphere.radius = FastMath.abs(ax * radius) + RADIUS_EPSILON - 1f;
return sphere;
}