dust3d/thirdparty/cgal/CGAL-4.13/include/CGAL/constructions/kernel_ftC3.h

901 lines
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C++
Executable File

// Copyright (c) 2000
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 3 of the License,
// or (at your option) any later version.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
// SPDX-License-Identifier: LGPL-3.0+
//
//
// Author(s) : Herve Bronnimann, Mariette Yvinec
#ifndef CGAL_CONSTRUCTIONS_KERNEL_FTC3_H
#define CGAL_CONSTRUCTIONS_KERNEL_FTC3_H
#include <CGAL/determinant.h>
#include <CGAL/number_utils.h>
namespace CGAL {
template < class FT >
CGAL_KERNEL_INLINE
void
midpointC3( const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
FT &x, FT &y, FT &z)
{
x = (px + qx) / 2;
y = (py + qy) / 2;
z = (pz + qz) / 2;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z,
FT &x, FT &y, FT &z)
{
FT w2 = 1 - w1;
x = w1 * p1x + w2 * p2x;
y = w1 * p1y + w2 * p2y;
z = w1 * p1z + w2 * p2z;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z, const FT &w2,
FT &x, FT &y, FT &z)
{
FT sum = w1 + w2;
CGAL_kernel_assertion(sum != 0);
x = (w1 * p1x + w2 * p2x) / sum;
y = (w1 * p1y + w2 * p2y) / sum;
z = (w1 * p1z + w2 * p2z) / sum;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z, const FT &w2,
const FT &p3x, const FT &p3y, const FT &p3z,
FT &x, FT &y, FT &z)
{
FT w3 = 1 - w1 - w2;
x = w1 * p1x + w2 * p2x + w3 * p3x;
y = w1 * p1y + w2 * p2y + w3 * p3y;
z = w1 * p1z + w2 * p2z + w3 * p3z;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z, const FT &w2,
const FT &p3x, const FT &p3y, const FT &p3z, const FT &w3,
FT &x, FT &y, FT &z)
{
FT sum = w1 + w2 + w3;
CGAL_kernel_assertion(sum != 0);
x = (w1 * p1x + w2 * p2x + w3 * p3x) / sum;
y = (w1 * p1y + w2 * p2y + w3 * p3y) / sum;
z = (w1 * p1z + w2 * p2z + w3 * p3z) / sum;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z, const FT &w2,
const FT &p3x, const FT &p3y, const FT &p3z, const FT &w3,
const FT &p4x, const FT &p4y, const FT &p4z,
FT &x, FT &y, FT &z)
{
FT w4 = 1 - w1 - w2 - w3;
x = w1 * p1x + w2 * p2x + w3 * p3x + w4 * p4x;
y = w1 * p1y + w2 * p2y + w3 * p3y + w4 * p4y;
z = w1 * p1z + w2 * p2z + w3 * p3z + w4 * p4z;
}
template < class FT >
void
barycenterC3(const FT &p1x, const FT &p1y, const FT &p1z, const FT &w1,
const FT &p2x, const FT &p2y, const FT &p2z, const FT &w2,
const FT &p3x, const FT &p3y, const FT &p3z, const FT &w3,
const FT &p4x, const FT &p4y, const FT &p4z, const FT &w4,
FT &x, FT &y, FT &z)
{
FT sum = w1 + w2 + w3 + w4;
CGAL_kernel_assertion(sum != 0);
x = (w1 * p1x + w2 * p2x + w3 * p3x + w4 * p4x) / sum;
y = (w1 * p1y + w2 * p2y + w3 * p3y + w4 * p4y) / sum;
z = (w1 * p1z + w2 * p2z + w3 * p3z + w4 * p4z) / sum;
}
template < class FT >
void
centroidC3( const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz,
const FT &sx, const FT &sy, const FT &sz,
FT &x, FT &y, FT &z)
{
x = (px + qx + rx + sx) / 4;
y = (py + qy + ry + sy) / 4;
z = (pz + qz + rz + sz) / 4;
}
template < class FT >
void
centroidC3( const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz,
FT &x, FT &y, FT &z)
{
x = (px + qx + rx) / 3;
y = (py + qy + ry) / 3;
z = (pz + qz + rz) / 3;
}
template < class FT >
CGAL_KERNEL_MEDIUM_INLINE
FT
squared_radiusC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz,
const FT &sx, const FT &sy, const FT &sz)
{
// Translate p to origin to simplify the expression.
FT qpx = qx-px;
FT qpy = qy-py;
FT qpz = qz-pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) + CGAL_NTS square(qpz);
FT rpx = rx-px;
FT rpy = ry-py;
FT rpz = rz-pz;
FT rp2 = CGAL_NTS square(rpx) + CGAL_NTS square(rpy) + CGAL_NTS square(rpz);
FT spx = sx-px;
FT spy = sy-py;
FT spz = sz-pz;
FT sp2 = CGAL_NTS square(spx) + CGAL_NTS square(spy) + CGAL_NTS square(spz);
FT num_x = determinant(qpy,qpz,qp2,
rpy,rpz,rp2,
spy,spz,sp2);
FT num_y = determinant(qpx,qpz,qp2,
rpx,rpz,rp2,
spx,spz,sp2);
FT num_z = determinant(qpx,qpy,qp2,
rpx,rpy,rp2,
spx,spy,sp2);
FT den = determinant(qpx,qpy,qpz,
rpx,rpy,rpz,
spx,spy,spz);
CGAL_kernel_assertion( ! CGAL_NTS is_zero(den) );
return (CGAL_NTS square(num_x) + CGAL_NTS square(num_y)
+ CGAL_NTS square(num_z)) / CGAL_NTS square(2 * den);
}
template < class FT >
CGAL_KERNEL_MEDIUM_INLINE
FT
squared_radiusC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &sx, const FT &sy, const FT &sz)
{
// Translate s to origin to simplify the expression.
FT psx = px-sx;
FT psy = py-sy;
FT psz = pz-sz;
FT ps2 = CGAL_NTS square(psx) + CGAL_NTS square(psy) + CGAL_NTS square(psz);
FT qsx = qx-sx;
FT qsy = qy-sy;
FT qsz = qz-sz;
FT qs2 = CGAL_NTS square(qsx) + CGAL_NTS square(qsy) + CGAL_NTS square(qsz);
FT rsx = psy*qsz-psz*qsy;
FT rsy = psz*qsx-psx*qsz;
FT rsz = psx*qsy-psy*qsx;
FT num_x = ps2 * determinant(qsy,qsz,rsy,rsz)
- qs2 * determinant(psy,psz,rsy,rsz);
FT num_y = ps2 * determinant(qsx,qsz,rsx,rsz)
- qs2 * determinant(psx,psz,rsx,rsz);
FT num_z = ps2 * determinant(qsx,qsy,rsx,rsy)
- qs2 * determinant(psx,psy,rsx,rsy);
FT den = determinant(psx,psy,psz,
qsx,qsy,qsz,
rsx,rsy,rsz);
CGAL_kernel_assertion( den != 0 );
return (CGAL_NTS square(num_x) + CGAL_NTS square(num_y)
+ CGAL_NTS square(num_z)) / CGAL_NTS square(2 * den);
}
template <class FT>
CGAL_KERNEL_MEDIUM_INLINE
void
plane_from_pointsC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz,
FT &pa, FT &pb, FT &pc, FT &pd)
{
FT rpx = px-rx;
FT rpy = py-ry;
FT rpz = pz-rz;
FT rqx = qx-rx;
FT rqy = qy-ry;
FT rqz = qz-rz;
// Cross product rp * rq
pa = rpy*rqz - rqy*rpz;
pb = rpz*rqx - rqz*rpx;
pc = rpx*rqy - rqx*rpy;
pd = - pa*rx - pb*ry - pc*rz;
}
template <class FT>
CGAL_KERNEL_MEDIUM_INLINE
void
plane_from_point_directionC3(const FT &px, const FT &py, const FT &pz,
const FT &dx, const FT &dy, const FT &dz,
FT &pa, FT &pb, FT &pc, FT &pd)
{
// d is the normal direction
pa = dx; pb = dy; pc = dz; pd = -dx*px - dy*py - dz*pz;
}
template <class FT>
CGAL_KERNEL_MEDIUM_INLINE
void
point_on_planeC3(const FT &pa, const FT &pb, const FT &pc, const FT &pd,
FT &x, FT &y, FT &z)
{
x = y = z = 0;
FT abs_pa = CGAL::abs(pa);
FT abs_pb = CGAL::abs(pb);
FT abs_pc = CGAL::abs(pc);
// to avoid badly defined point with an overly large coordinate when
// the plane is almost orthogonal to one axis, we use the largest
// scalar coordinate instead of always using the first non-null
if (abs_pa >= abs_pb && abs_pa >= abs_pc)
x = -pd/pa;
else if (abs_pb >= abs_pa && abs_pb >= abs_pc)
y = -pd/pb;
else
z = -pd/pc;
}
template <class FT>
CGAL_KERNEL_MEDIUM_INLINE
void
projection_planeC3(const FT &pa, const FT &pb, const FT &pc, const FT &pd,
const FT &px, const FT &py, const FT &pz,
FT &x, FT &y, FT &z)
{
// the equation of the plane is Ax+By+Cz+D=0
// the normal direction is (A,B,C)
// the projected point is p-lambda(A,B,C) where
// A(x-lambda A) + B(y-lambda B) + C(z-lambda C) + D = 0
FT num = pa*px + pb*py + pc*pz + pd;
FT den = pa*pa + pb*pb + pc*pc;
FT lambda = num / den;
x = px - lambda * pa;
y = py - lambda * pb;
z = pz - lambda * pc;
}
template < class FT >
CGAL_KERNEL_INLINE
FT
squared_distanceC3( const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz)
{
return CGAL_NTS square(px-qx) + CGAL_NTS square(py-qy) +
CGAL_NTS square(pz-qz);
}
template < class FT >
CGAL_KERNEL_INLINE
FT
squared_radiusC3( const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz)
{
return squared_distanceC3(px, py, pz, qx, qy, qz) / 4;
}
template < class FT >
CGAL_KERNEL_INLINE
FT
scaled_distance_to_directionC3(const FT &pa, const FT &pb, const FT &pc,
const FT &px, const FT &py, const FT &pz)
{
return pa*px + pb*py + pc*pz;
}
template < class FT >
CGAL_KERNEL_INLINE
FT
scaled_distance_to_planeC3(
const FT &pa, const FT &pb, const FT &pc, const FT &pd,
const FT &px, const FT &py, const FT &pz)
{
return pa*px + pb*py + pc*pz + pd;
}
template < class FT >
CGAL_KERNEL_INLINE
FT
scaled_distance_to_planeC3(
const FT &ppx, const FT &ppy, const FT &ppz,
const FT &pqx, const FT &pqy, const FT &pqz,
const FT &prx, const FT &pry, const FT &prz,
const FT &px, const FT &py, const FT &pz)
{
return determinant(ppx-px,ppy-py,ppz-pz,
pqx-px,pqy-py,pqz-pz,
prx-px,pry-py,prz-pz);
}
template < class FT >
CGAL_KERNEL_INLINE
void
bisector_of_pointsC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
FT &a, FT &b, FT &c, FT &d)
{
a = 2*(px - qx);
b = 2*(py - qy);
c = 2*(pz - qz);
d = CGAL_NTS square(qx) + CGAL_NTS square(qy) + CGAL_NTS square(qz)
- CGAL_NTS square(px) - CGAL_NTS square(py) - CGAL_NTS square(pz);
}
template < class FT >
void
bisector_of_planesC3(const FT &pa, const FT &pb, const FT &pc, const FT &pd,
const FT &qa, const FT &qb, const FT &qc, const FT &qd,
FT &a, FT &b, FT &c, FT &d)
{
// We normalize the equations of the 2 planes, and we then add them.
FT n1 = CGAL_NTS sqrt(CGAL_NTS square(pa) + CGAL_NTS square(pb) +
CGAL_NTS square(pc));
FT n2 = CGAL_NTS sqrt(CGAL_NTS square(qa) + CGAL_NTS square(qb) +
CGAL_NTS square(qc));
a = n2 * pa + n1 * qa;
b = n2 * pb + n1 * qb;
c = n2 * pc + n1 * qc;
d = n2 * pd + n1 * qd;
// Care must be taken for the case when this produces a degenerate line.
if (a == 0 && b == 0 && c == 0) {
a = n2 * pa - n1 * qa;
b = n2 * pb - n1 * qb;
c = n2 * pc - n1 * qc;
d = n2 * pd - n1 * qd;
}
}
template < class FT >
FT
squared_areaC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz)
{
// Compute vectors pq and pr, then the cross product,
// then 1/4 of its squared length.
FT dqx = qx-px;
FT dqy = qy-py;
FT dqz = qz-pz;
FT drx = rx-px;
FT dry = ry-py;
FT drz = rz-pz;
FT vx = dqy*drz-dqz*dry;
FT vy = dqz*drx-dqx*drz;
FT vz = dqx*dry-dqy*drx;
return (CGAL_NTS square(vx) + CGAL_NTS square(vy) + CGAL_NTS square(vz))/4;
}
template <class FT>
void
determinants_for_weighted_circumcenterC3(
const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw,
FT &num_x, FT &num_y, FT &num_z, FT& den)
{
// translate origin to p
// and compute determinants for weighted_circumcenter and
// circumradius
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz) - qw + pw;
FT rpx = rx - px;
FT rpy = ry - py;
FT rpz = rz - pz;
FT rp2 = CGAL_NTS square(rpx) + CGAL_NTS square(rpy) +
CGAL_NTS square(rpz) - rw + pw;
FT spx = sx - px;
FT spy = sy - py;
FT spz = sz - pz;
FT sp2 = CGAL_NTS square(spx) + CGAL_NTS square(spy) +
CGAL_NTS square(spz) - sw + pw;
num_x = determinant(qpy,qpz,qp2,
rpy,rpz,rp2,
spy,spz,sp2);
num_y = determinant(qpx,qpz,qp2,
rpx,rpz,rp2,
spx,spz,sp2);
num_z = determinant(qpx,qpy,qp2,
rpx,rpy,rp2,
spx,spy,sp2);
den = determinant(qpx,qpy,qpz,
rpx,rpy,rpz,
spx,spy,spz);
}
template <class FT>
void
determinants_for_circumcenterC3(const FT &px, const FT &py, const FT &pz,
const FT &qx, const FT &qy, const FT &qz,
const FT &rx, const FT &ry, const FT &rz,
const FT &sx, const FT &sy, const FT &sz,
FT &num_x, FT &num_y, FT &num_z, FT& den)
{
// translate origin to p
// and compute determinants for weighted_circumcenter and
// circumradius
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz);
FT rpx = rx - px;
FT rpy = ry - py;
FT rpz = rz - pz;
FT rp2 = CGAL_NTS square(rpx) + CGAL_NTS square(rpy) +
CGAL_NTS square(rpz);
FT spx = sx - px;
FT spy = sy - py;
FT spz = sz - pz;
FT sp2 = CGAL_NTS square(spx) + CGAL_NTS square(spy) +
CGAL_NTS square(spz);
num_x = determinant(qpy,qpz,qp2,
rpy,rpz,rp2,
spy,spz,sp2);
num_y = determinant(qpx,qpz,qp2,
rpx,rpz,rp2,
spx,spz,sp2);
num_z = determinant(qpx,qpy,qp2,
rpx,rpy,rp2,
spx,spy,sp2);
den = determinant(qpx,qpy,qpz,
rpx,rpy,rpz,
spx,spy,spz);
}
template < class FT>
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw,
FT &x, FT &y, FT &z)
{
// this function computes the weighted circumcenter point only
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
sx, sy, sz, sw,
num_x, num_y, num_z,den);
CGAL_assertion( ! CGAL_NTS is_zero(den) );
FT inv = FT(1)/(FT(2) * den);
x = px + num_x*inv;
y = py - num_y*inv;
z = pz + num_z*inv;
}
template < class FT>
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw,
FT &x, FT &y, FT &z, FT &w)
{
// this function computes the weighted circumcenter point
// and the squared weighted circumradius
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
sx, sy, sz, sw,
num_x, num_y, num_z, den);
CGAL_assertion( ! CGAL_NTS is_zero(den) );
FT inv = FT(1)/(FT(2) * den);
x = px + num_x*inv;
y = py - num_y*inv;
z = pz + num_z*inv;
w = (CGAL_NTS square(num_x) + CGAL_NTS square(num_y) + CGAL_NTS square(num_z))
* CGAL_NTS square(inv) - pw;
}
template< class FT >
FT
squared_radius_orthogonal_sphereC3(
const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw)
{
// this function computes the squared weighted circumradius only
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
sx, sy, sz, sw,
num_x, num_y, num_z,den);
CGAL_assertion( ! CGAL_NTS is_zero(den) );
FT inv = FT(1)/(FT(2) * den);
return (CGAL_NTS square(num_x) + CGAL_NTS square(num_y) + CGAL_NTS square(num_z))
* CGAL_NTS square(inv) - pw;
}
template <class FT>
void
determinants_for_weighted_circumcenterC3(
const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
FT &num_x, FT &num_y, FT &num_z, FT &den)
{
// translate origin to p and compute determinants for weighted_circumcenter
// and circumradius
// Translate s to origin to simplify the expression.
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz) - qw + pw;
FT rpx = rx - px;
FT rpy = ry - py;
FT rpz = rz - pz;
FT rp2 = CGAL_NTS square(rpx) + CGAL_NTS square(rpy) +
CGAL_NTS square(rpz) - rw + pw;
FT sx = qpy*rpz - qpz*rpy;
FT sy = qpz*rpx - qpx*rpz;
FT sz = qpx*rpy - qpy*rpx;
// The following determinants can be developped and simplified.
//
// FT num_x = determinant(qpy,qpz,qp2,
// rpy,rpz,rp2,
// sy,sz,FT(0));
// FT num_y = determinant(qpx,qpz,qp2,
// rpx,rpz,rp2,
// sx,sz,FT(0));
// FT num_z = determinant(qpx,qpy,qp2,
// rpx,rpy,rp2,
// sx,sy,FT(0));
num_x = qp2 * determinant(rpy,rpz,sy,sz)
- rp2 * determinant(qpy,qpz,sy,sz);
num_y = qp2 * determinant(rpx,rpz,sx,sz)
- rp2 * determinant(qpx,qpz,sx,sz);
num_z = qp2 * determinant(rpx,rpy,sx,sy)
- rp2 * determinant(qpx,qpy,sx,sy);
den = determinant(qpx,qpy,qpz,
rpx,rpy,rpz,
sx,sy,sz);
}
template < class FT >
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
FT &x, FT &y, FT &z)
{
// this function computes the weighted circumcenter point only
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
num_x, num_y, num_z, den);
CGAL_assertion( den != FT(0) );
FT inv = FT(1) / (FT(2) * den);
x = px + num_x*inv;
y = py - num_y*inv;
z = pz + num_z*inv;
}
template < class FT >
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
FT &x, FT &y, FT &z, FT &w)
{
// this function computes the weighted circumcenter and
// the weighted squared circumradius
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
num_x, num_y, num_z, den);
CGAL_assertion( den != FT(0) );
FT inv = FT(1) / (FT(2) * den);
x = px + num_x*inv;
y = py - num_y*inv;
z = pz + num_z*inv;
w = (CGAL_NTS square(num_x) + CGAL_NTS square(num_y) + CGAL_NTS square(num_z))
*CGAL_NTS square(inv) - pw;
}
template< class FT >
CGAL_MEDIUM_INLINE
FT
squared_radius_smallest_orthogonal_sphereC3(
const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw)
{
// this function computes the weighted squared circumradius only
// Translate p to origin and compute determinants
FT num_x, num_y, num_z, den;
determinants_for_weighted_circumcenterC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
num_x, num_y, num_z, den);
CGAL_assertion( den != FT(0) );
FT inv = FT(1)/(FT(2) * den);
return (CGAL_NTS square(num_x) + CGAL_NTS square(num_y) + CGAL_NTS square(num_z))
* CGAL_NTS square(inv) - pw;
}
template < class FT >
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
FT &x, FT &y, FT &z)
{
// this function computes the weighted circumcenter point only
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz);
FT inv = FT(1) / (FT(2) * qp2);
FT alpha = 1 / FT(2) + (pw-qw) * inv;
x = px + alpha * qpx;
y = py + alpha * qpy;
z = pz + alpha * qpz;
}
template < class FT >
void
weighted_circumcenterC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
FT &x, FT &y, FT &z, FT &w)
{
// this function computes the weighted circumcenter point and
// the weighted circumradius
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz);
FT inv = FT(1) / (FT(2) * qp2);
FT alpha = 1 / FT(2) + (pw-qw) * inv;
x = px + alpha * qpx;
y = py + alpha * qpy;
z = pz + alpha * qpz;
w = CGAL_NTS square(alpha) * qp2 - pw;
}
template< class FT >
CGAL_MEDIUM_INLINE
FT
squared_radius_smallest_orthogonal_sphereC3(
const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw)
{
// this function computes the weighted circumradius only
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz);
FT inv = FT(1) / (FT(2) * qp2);
FT alpha = 1 / FT(2) + (pw-qw) * inv;
return CGAL_NTS square(alpha)*qp2 - pw;
}
template< class FT >
FT
power_productC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw)
{
// computes the power product of two weighted points
FT qpx = qx - px;
FT qpy = qy - py;
FT qpz = qz - pz;
FT qp2 = CGAL_NTS square(qpx) + CGAL_NTS square(qpy) +
CGAL_NTS square(qpz);
return qp2 - pw - qw ;
}
template < class RT , class We>
void
radical_axisC3(const RT &px, const RT &py, const RT &pz, const We & /* pw */,
const RT &qx, const RT &qy, const RT &qz, const We & /* qw */,
const RT &rx, const RT &ry, const RT &rz, const We & /* rw */,
RT &a, RT &b, RT& c )
{
RT dqx=qx-px, dqy=qy-py, dqz=qz-pz, drx=rx-px, dry=ry-py, drz=rz-pz;
//il manque des tests...
a = RT(1)*determinant(dqy, dqz, dry, drz);
b = - RT(1)*determinant(dqx, dqz, drx, drz);
c = RT(1)*determinant(dqx, dqy, drx, dry);
}
// function used in critical_squared_radiusC3
// power ( t, tw) with respect to
// circle orthogonal (p,pw), (q,qw), (r,rw), (s,sw)
template < class FT>
FT
power_to_orthogonal_sphereC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw,
const FT &tx, const FT &ty, const FT &tz, const FT &tw)
{
//to get the value of the determinant
// We translate the points so that t becomes the origin.
FT dpx = px - tx;
FT dpy = py - ty;
FT dpz = pz - tz;
FT dpt = CGAL_NTS square(dpx) + CGAL_NTS square(dpy) +
CGAL_NTS square(dpz) - pw + tw ;
FT dqx = qx - tx;
FT dqy = qy - ty;
FT dqz = qz - tz;
FT dqt = CGAL_NTS square(dqx) + CGAL_NTS square(dqy) +
CGAL_NTS square(dqz) - qw + tw;
FT drx = rx - tx;
FT dry = ry - ty;
FT drz = rz - tz;
FT drt = CGAL_NTS square(drx) + CGAL_NTS square(dry) +
CGAL_NTS square(drz) - rw + tw;
FT dsx = sx - tx;
FT dsy = sy - ty;
FT dsz = sz - tz;
FT dst = CGAL_NTS square(dsx) + CGAL_NTS square(dsy) +
CGAL_NTS square(dsz) - sw + tw;
return determinant(dpx, dpy, dpz, dpt,
dqx, dqy, dqz, dqt,
drx, dry, drz, drt,
dsx, dsy, dsz, dst);
}
// compute the critical weight tw
// where weighted point t is orthogonal to weighted points p, q,r,s
template < class FT>
FT
power_distance_to_power_sphereC3(const FT &px, const FT &py, const FT &pz, const FT &pw,
const FT &qx, const FT &qy, const FT &qz, const FT &qw,
const FT &rx, const FT &ry, const FT &rz, const FT &rw,
const FT &sx, const FT &sy, const FT &sz, const FT &sw,
const FT &tx, const FT &ty, const FT &tz, const FT & )
{
// the 5x5 det is a linear function of tw ff(tw)= ff(0) + tw ff(1)
// the critical value for tw is - ff(0)/( ff(1) - ff(0))
FT ff0 = power_to_orthogonal_sphereC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
sx, sy, sz, sw,
tx, ty, tz, FT(0));
FT ff1 = power_to_orthogonal_sphereC3(px, py, pz, pw,
qx, qy, qz, qw,
rx, ry, rz, rw,
sx, sy, sz, sw,
tx, ty, tz, FT(1));
return -ff0/(ff1 - ff0);
}
// I will use this to test if the radial axis of three spheres
// intersect the triangle formed by the centers.
// // resolution of the system (where we note c the center)
// // | dc^2 = cw + rw
// // | (dp-dc)^2 = pw + cw
// // | (dq-dc)^2 = qw + cw
// // | dc = Lamdba*dp + Mu*dq
// FT FT2(2);
// FT dpx = px-rx;
// FT dpy = py-ry;
// FT dpz = pz-rz;
// FT dp = CGAL_NTS square(dpx)+CGAL_NTS square(dpy)+CGAL_NTS square(dpz);
// FT dpp = dp-pw+rw;
// FT dqx = qx-rx;
// FT dqy = qy-ry;
// FT dqz = qz-rz;
// FT dq = CGAL_NTS square(dqx)+CGAL_NTS square(dqy)+CGAL_NTS square(dqz);
// FT dqq = dq-qw+rw;
// FT dpdq = dpx*dqx+dpy*dqy+dpz*dqz;
// FT denom = FT2*(dp*dq-CGAL_NTS square(dpdq));
// FT Lambda = (dpp*dq-dqq*dpdq)/denom;
// FT Mu = (dqq*dp-dpp*dpdq)/denom;
// return (CGAL_NTS square(Lambda)*dp+CGAL_NTS square(Mu)*dq
// + FT2*Lambda*Mu*dpdq - rw);
} //namespace CGAL
#endif // CGAL_CONSTRUCTIONS_KERNEL_FTC3_H