mirror of
https://github.com/opencv/opencv.git
synced 2024-12-11 22:59:16 +08:00
178 lines
4.6 KiB
C++
178 lines
4.6 KiB
C++
///////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
|
|
// Digital Ltd. LLC
|
|
//
|
|
// All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions are
|
|
// met:
|
|
// * Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// * Redistributions in binary form must reproduce the above
|
|
// copyright notice, this list of conditions and the following disclaimer
|
|
// in the documentation and/or other materials provided with the
|
|
// distribution.
|
|
// * Neither the name of Industrial Light & Magic nor the names of
|
|
// its contributors may be used to endorse or promote products derived
|
|
// from this software without specific prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////
|
|
|
|
|
|
|
|
#ifndef INCLUDED_IMATHSPHERE_H
|
|
#define INCLUDED_IMATHSPHERE_H
|
|
|
|
//-------------------------------------
|
|
//
|
|
// A 3D sphere class template
|
|
//
|
|
//-------------------------------------
|
|
|
|
#include "ImathVec.h"
|
|
#include "ImathBox.h"
|
|
#include "ImathLine.h"
|
|
|
|
namespace Imath {
|
|
|
|
template <class T>
|
|
class Sphere3
|
|
{
|
|
public:
|
|
|
|
Vec3<T> center;
|
|
T radius;
|
|
|
|
//---------------
|
|
// Constructors
|
|
//---------------
|
|
|
|
Sphere3() : center(0,0,0), radius(0) {}
|
|
Sphere3(const Vec3<T> &c, T r) : center(c), radius(r) {}
|
|
|
|
//-------------------------------------------------------------------
|
|
// Utilities:
|
|
//
|
|
// s.circumscribe(b) sets center and radius of sphere s
|
|
// so that the s tightly encloses box b.
|
|
//
|
|
// s.intersectT (l, t) If sphere s and line l intersect, then
|
|
// intersectT() computes the smallest t,
|
|
// t >= 0, so that l(t) is a point on the
|
|
// sphere. intersectT() then returns true.
|
|
//
|
|
// If s and l do not intersect, intersectT()
|
|
// returns false.
|
|
//
|
|
// s.intersect (l, i) If sphere s and line l intersect, then
|
|
// intersect() calls s.intersectT(l,t) and
|
|
// computes i = l(t).
|
|
//
|
|
// If s and l do not intersect, intersect()
|
|
// returns false.
|
|
//
|
|
//-------------------------------------------------------------------
|
|
|
|
void circumscribe(const Box<Vec3<T> > &box);
|
|
bool intersect(const Line3<T> &l, Vec3<T> &intersection) const;
|
|
bool intersectT(const Line3<T> &l, T &t) const;
|
|
};
|
|
|
|
|
|
//--------------------
|
|
// Convenient typedefs
|
|
//--------------------
|
|
|
|
typedef Sphere3<float> Sphere3f;
|
|
typedef Sphere3<double> Sphere3d;
|
|
|
|
|
|
//---------------
|
|
// Implementation
|
|
//---------------
|
|
|
|
template <class T>
|
|
void Sphere3<T>::circumscribe(const Box<Vec3<T> > &box)
|
|
{
|
|
center = T(0.5) * (box.min + box.max);
|
|
radius = (box.max - center).length();
|
|
}
|
|
|
|
|
|
template <class T>
|
|
bool Sphere3<T>::intersectT(const Line3<T> &line, T &t) const
|
|
{
|
|
bool doesIntersect = true;
|
|
|
|
Vec3<T> v = line.pos - center;
|
|
T B = T(2.0) * (line.dir ^ v);
|
|
T C = (v ^ v) - (radius * radius);
|
|
|
|
// compute discriminant
|
|
// if negative, there is no intersection
|
|
|
|
T discr = B*B - T(4.0)*C;
|
|
|
|
if (discr < 0.0)
|
|
{
|
|
// line and Sphere3 do not intersect
|
|
|
|
doesIntersect = false;
|
|
}
|
|
else
|
|
{
|
|
// t0: (-B - sqrt(B^2 - 4AC)) / 2A (A = 1)
|
|
|
|
T sqroot = Math<T>::sqrt(discr);
|
|
t = (-B - sqroot) * T(0.5);
|
|
|
|
if (t < 0.0)
|
|
{
|
|
// no intersection, try t1: (-B + sqrt(B^2 - 4AC)) / 2A (A = 1)
|
|
|
|
t = (-B + sqroot) * T(0.5);
|
|
}
|
|
|
|
if (t < 0.0)
|
|
doesIntersect = false;
|
|
}
|
|
|
|
return doesIntersect;
|
|
}
|
|
|
|
|
|
template <class T>
|
|
bool Sphere3<T>::intersect(const Line3<T> &line, Vec3<T> &intersection) const
|
|
{
|
|
T t;
|
|
|
|
if (intersectT (line, t))
|
|
{
|
|
intersection = line(t);
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
|
|
} //namespace Imath
|
|
|
|
#endif
|