+++ /dev/null
-///////////////////////////////////////////////////////////////////////////
-//
-// 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 = 2.0 * (line.dir ^ v);
- T C = (v ^ v) - (radius * radius);
-
- // compute discriminant
- // if negative, there is no intersection
-
- T discr = B*B - 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) * 0.5;
-
- if (t < 0.0)
- {
- // no intersection, try t1: (-B + sqrt(B^2 - 4AC)) / 2A (A = 1)
-
- t = (-B + sqroot) * 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
projects / opencv / blobdiff