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hard code that Poincare disc center = Point_2(cgal origin) and its [squared] radius = FT(1)

This commit is contained in:
Monique Teillaud 2016-08-03 18:32:52 +02:00 committed by Iordan Iordanov
parent dd573d7cd4
commit 359cfc4085
1 changed files with 32 additions and 28 deletions
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60
Hyperbolic_triangulation_2/include/CGAL/Hyperbolic_triangulation_traits_2.h
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@ -81,13 +81,13 @@ public:
private:
// Poincaré disk
const Circle_2 _unit_circle;
const Circle_2 _unit_circle;
public:
const Circle_2& unit_circle() const
{
return _unit_circle;
}
const Circle_2& unit_circle() const
{
return _unit_circle;
}
class Construct_segment_2
{
@ -97,19 +97,20 @@ public:
typedef typename Regular_geometric_traits_2::Bare_point Bare_point;
public:
Construct_segment_2(const Circle_2& c) : _unit_circle(c)
{
}
Construct_segment_2(const Circle_2& c) : _unit_circle(c)
{
}
Hyperbolic_segment_2 operator()(const Point_2& p, const Point_2& q) const
{
if(Euclidean_collinear_2()(p, q, _unit_circle.center())){
Origin o;
if(Euclidean_collinear_2()(p, q, Point_2(o))){
return Euclidean_segment_2(p, q);
}
Weighted_point_2 wp(p);
Weighted_point_2 wq(q);
Weighted_point_2 wo(_unit_circle.center(), _unit_circle.squared_radius());
Weighted_point_2 wo(Point_2(o), FT(1)); // Poincaré circle
Bare_point center = Construct_weighted_circumcenter_2()(wp, wo, wq);
FT radius = Compute_squared_Euclidean_distance_2()(p, center);
@ -151,16 +152,16 @@ public:
// circle must be inside the unit one
assert(CGAL::do_intersect(_unit_circle, circle) == false);
if(circle.center() <= _unit_circle.center() && circle.center() >= _unit_circle.center()){
return _unit_circle.center();
}
Origin o;
Point_2 po = Point_2(o);
if (circle.center() == po)
{ return po; }
FT x0 = circle.center().x(), y0 = circle.center().y();
// a*alphaˆ2 + b*alpha + c = 0;
FT a = x0*x0 + y0*y0;
FT b = a - circle.squared_radius() + _unit_circle.squared_radius();
FT c = _unit_circle.squared_radius();
FT D = b*b - 4*a*c;
FT b = a - circle.squared_radius() + FT(1); // Poincare disc has radius 1
FT D = b*b - 4*a*FT(1);
FT alpha = (b - CGAL::sqrt(to_double(D)))/(2*a);
@ -234,8 +235,9 @@ public:
// At present time, in this case the bisector is supported by the line.
Compute_squared_Euclidean_distance_2 dist = Compute_squared_Euclidean_distance_2();
Point_2 origin = _unit_circle.center();
FT dif = dist(origin, p) - dist(origin, q);
Origin o;
Point_2 po = Point_2(o);
FT dif = dist(po, p) - dist(po, q);
FT eps = 0.0000000001;
// Bisector is straight in euclidean sense
@ -275,11 +277,11 @@ public:
// xˆ2 + yˆ2 - rˆ2 = Rˆ2, where R - is a radius of the given unit circle
FT op = p.x()*p.x() + p.y()*p.y();
FT oq = q.x()*q.x() + q.y()*q.y();
FT alpha = (_unit_circle.squared_radius() - oq) / (op - oq);
FT alpha = (FT(1) - oq) / (op - oq); // Poincare disc has radius 1
FT x = alpha*p.x() + (1-alpha)*q.x();
FT y = alpha*p.y() + (1-alpha)*q.y();
FT radius = x*x + y*y - _unit_circle.squared_radius();
FT radius = x*x + y*y - FT(1);
//improve
Euclidean_line_2 l = Construct_Euclidean_bisector_2()(p, q);
@ -292,7 +294,7 @@ public:
return Circle_2(Point_2(x, y), radius, COUNTERCLOCKWISE);
}
// Find intersection of an input circle orthogonal to the Poincaré disk
// Find intersection of an input circle orthogonal to the Poincare disk
// and the circle representing this disk
// TODO: sqrt(to_double()?)
@ -302,20 +304,22 @@ public:
// axˆ2 + 2bˆx + c = 0;
FT a = x*x + y*y;
FT b = -_unit_circle.squared_radius() * x;
FT c = _unit_circle.squared_radius()*_unit_circle.squared_radius() - _unit_circle.squared_radius()*y*y;
/* FT b = -_unit_circle.squared_radius() * x; */
/* FT c = _unit_circle.squared_radius()*_unit_circle.squared_radius() - _unit_circle.squared_radius()*y*y; */
FT b = -x;
FT c = 1-y*y;
assert(b*b - a*c > 0);
FT D = CGAL::sqrt(to_double(b*b - a*c));
FT x1 = (-b - D)/a;
FT x2 = (-b + D)/a;
FT y1 = (_unit_circle.squared_radius() - x1*x)/y;
FT y2 = (_unit_circle.squared_radius() - x2*x)/y;
FT y1 = (FT(1) - x1*x)/y;
FT y2 = (FT(1) - x2*x)/y;
return std::make_pair(Point_2(x1, y1), Point_2(x2, y2));
}
// Find intersection of an input line orthogonal to the Poincaré disk
// Find intersection of an input line orthogonal to the Poincare disk
// and the circle representing this disk
// TODO: sqrt(to_double()?)
@ -325,7 +329,7 @@ public:
Vector_2 v = l.to_vector();
// normalize the vector
FT squared_coeff = _unit_circle.squared_radius()/v.squared_length();
FT squared_coeff = FT(1)/v.squared_length();
FT coeff = CGAL::sqrt(to_double(squared_coeff));
Point_2 p1(coeff*v.x(), coeff*v.y());