OSG_BASE_DLLMAPPING
bool intersect(const CylinderVolume &cyl1,
const CylinderVolume &cyl2)
{
Pnt3f p1, p2;
Vec3f v1, v2;
cyl1.getAxis(p1, v1);
cyl2.getAxis(p2, v2);
return dist3D_Segment_to_Segment(p1, v1, p2, v2) <=
(cyl1.getRadius() + cyl2.getRadius());
}
OSG_BASE_DLLMAPPING
bool intersect(const BoxVolume &box, const CylinderVolume &cylinder)
{
bool retCode;
Pnt3f apos;
Vec3f adir;
cylinder.getAxis(apos, adir);
if(box.isEmpty() == true || cylinder.isEmpty() == true)
{
retCode = false;
}
else if(box.isInfinite() == true || cylinder.isInfinite() == true)
{
retCode = true;
}
else
{
Real32 s1 = 0, s2 = 0, s3 = 0, s4 = 0, d = 0, d1 = 0, d2 = 0;
Pnt3f c, p, p1, p2;
Vec3f u, u1, u2;
// find the distance between the min and the max of the box
//with the lower point and the upper point of the cylinder respectively
s1 = (apos - box.getMin()).length();
s2 = (apos - box.getMax()).length();
s3 = (apos + adir - box.getMin()).length();
s4 = (apos + adir - box.getMax()).length();
//Check the minimum of the above distances
if(s1 <= s2)
{
d1 = s1;
p1 = box.getMin();
}
else
{
d1 = s2;
p1 = box.getMax();
}
if(s3 <= s4)
{
d2 = s3;
p2 = box.getMin();
}
else
{
d2 = s4;
p2 = box.getMax();
}
//set the value of the vector corresponding to the shortest distance
if(d1 <= d2)
{
d = d1;
c = apos;
p = p1;
}
else
{
d = d2;
c = apos + adir;
p = p2;
}
// decompose the vector in u1 and u2 which are parallel and
// perpendicular to the cylinder axis respectively
u = p - c;
u1 = (u[0] * adir[0] + u[1] * adir[1] + u[2] * adir[2]) /
(adir.length() * adir.length()) * adir;
u2 = u - u1;
if(u1.length() <= 10e-6)
{
retCode = true;
}
else if(u2.length() <= 10e-6)
{
retCode = (d <= 10e-6);
}
else
{
retCode = (u2.length() <= cylinder.getRadius());
}
}
return retCode;
}
OSG_BASE_DLLMAPPING
bool intersect(const SphereVolume &sphere, const CylinderVolume &cylinder)
{
bool retCode;
Pnt3f apos;
Vec3f adir;
cylinder.getAxis(apos, adir);
if(sphere.isEmpty() || cylinder.isEmpty())
{
retCode = false;
}
else if(sphere.isInfinite() || cylinder.isInfinite())
{
retCode = true;
}
else
{
Real32 d = 0.f, s1 = 0.f, s2 = 0.f;
Pnt3f c;
Vec3f u, u1, u2;
//get the distance between the upper and lower point of the cylinder
// and the sphere center
s1 = (apos - sphere.getCenter()).length();
s2 = (apos + adir - sphere.getCenter()).length();
if ((s1<=DBL_EPSILON) || (s2<=DBL_EPSILON))
return true;
//check the smallest distance and set the vector coordinate
if(s1 <= s2)
{
d = s1;
c = apos;
}
else
{
d = s2;
c = apos + adir;
}
// decompose the vector in u1 and u2 which are parallel and
// perpendicular to the cylinder axis respectively
u = ((d - sphere.getRadius()) / d) * (c - sphere.getCenter());
u1 = (u[0] * adir[0] + u[1] * adir[1] + u[2] * adir[2]) /
(adir.length() * adir.length()) * adir;
u2 = u - u1;
if(u2.length() <= 10e-6)
{
retCode = (d <= sphere.getRadius());
}
else
{
retCode = (u2.length() <= cylinder.getRadius());
}
}
return retCode;
}
bool Line::intersect(const CylinderVolume &cyl,
Real &enter,
Real &exit ) const
{
Real radius = cyl.getRadius();
Vec3r adir;
Vec3r o_adir;
Pnt3r apos;
cyl.getAxis(apos, adir);
o_adir = adir;
adir.normalize();
bool isect;
Real ln;
Real dl;
Vec3r RC;
Vec3r n;
Vec3r D;
RC = _pos - apos;
n = _dir.cross (adir);
ln = n .length( );
if(ln == 0.f) // IntersectionLine is parallel to CylinderAxis
{
D = RC - (RC.dot(adir)) * adir;
dl = D.length();
if(dl <= radius) // line lies in cylinder
{
enter = 0.f;
exit = Inf;
}
else
{
return false;
}
}
else
{
n.normalize();
dl = osgAbs(RC.dot(n)); //shortest distance
isect = (dl <= radius);
if(isect)
{ // if ray hits cylinder
Real t;
Real s;
Vec3r O;
O = RC.cross(adir);
t = - (O.dot(n)) / ln;
O = n.cross(adir);
O.normalize();
s = osgAbs (
(osgSqrt ((radius * radius) - (dl * dl))) / (_dir.dot(O)));
exit = t + s;
if(exit < 0.f)
return false;
enter = t - s;
if(enter < 0.f)
enter = 0.f;
}
else
{
return false;
}
}
Real t;
Plane bottom(-adir, apos);
if(bottom.intersect(*this, t))
{
if(bottom.isInHalfSpace(_pos))
{
if(t > enter)
enter = t;
}
else
{
if(t < exit)
exit = t;
}
}
else
{
if(bottom.isInHalfSpace(_pos))
return false;
}
Plane top(adir, apos + o_adir);
if(top.intersect(*this, t))
{
if(top.isInHalfSpace(_pos))
{
if(t > enter)
enter = t;
}
else
{
if(t < exit)
exit = t;
}
}
else
{
if(top.isInHalfSpace(_pos))
return false;
}
return (enter < exit);
}
