bool Rectangle::Intersects(const Circle& circle) const {
double radius = circle.GetRadius();
auto cp = circle.GetPosition();
auto t = GetTop();
double distTop = Math::GetDistance(cp, t.GetPointOne(), t.GetPointTwo());
auto l = GetLeft();
double distLeft = Math::GetDistance(cp, l.GetPointOne(), l.GetPointTwo());
auto r = GetRight();
double distRight = Math::GetDistance(cp, r.GetPointOne(), r.GetPointTwo());
auto b = GetBottom();
double distBottom = Math::GetDistance(cp, b.GetPointOne(), b.GetPointTwo());
bool resultTop = distTop <= radius;
bool resultLeft = distLeft <= radius;
bool resultRight = distRight <= radius;
bool resultBottom = distBottom <= radius;
bool isInside = Intersects(Point(circle.GetPosition()));
return (isInside || resultTop || resultLeft || resultRight || resultBottom);
}
bool Line::Intersects(const Circle& circle) const {
double r2 = circle.GetRadius();
r2 *= r2;
bool eOne_result = ((_extent_one - circle.GetPosition()).GetLengthSquared() < r2);
bool eTwo_result = ((_extent_two - circle.GetPosition()).GetLengthSquared() < r2);
if(eOne_result) return true;
if(eTwo_result) return true;
return this->GetDistance(Point(circle.GetPosition())) <= circle.GetRadius();
}
bool Sector::Intersects(const Circle& circle) const {
//Intersections performed fast to slow.
//FAST:
//If bounding circle and argument circle do not intersect: no.
//If initial point intersects circle: yes.
//If terminal point intersects circle: yes.
//If central point intersects circle: yes.
//SLOW:
//If the angle between the circle and the sector is in-between the start and end angles (mapped to [0, 2pi]): yes.
//If the circle intersects the initial line: yes.
//If the circle intersects the terminal line: yes.
//Otherwise: no.
double my_x = this->GetX();
double my_y = this->GetY();
double your_x = circle.GetX();
double your_y = circle.GetY();
double radius_sum = this->GetRadius() + circle.GetRadius();
if(a2de::Point::GetDistance(my_x, my_y, your_x, your_y) > radius_sum) return false;
if(this->GetStartPoint().Intersects(circle)) return true;
if(this->GetEndPoint().Intersects(circle)) return true;
if(Point(this->GetPosition()).Intersects(circle)) return true;
double angle = Vector2D::GetFacingAngle(circle.GetPosition(), this->GetPosition());
//Map return values to [0, 360]
double sA = this->GetStartAngle();
if(sA > Math::A2DE_PI) {
sA -= Math::A2DE_2PI;
}
double eA = this->GetEndAngle();
if(eA > Math::A2DE_PI) {
eA -= Math::A2DE_2PI;
}
bool within_sector = (sA <= angle && angle <= eA);
if(within_sector) return true;
Line sl(this->GetPosition(), this->GetStartPoint().GetPosition());
Line tl(this->GetPosition(), this->GetEndPoint().GetPosition());
if(sl.Intersects(circle)) return true;
if(tl.Intersects(circle)) return true;
return false;
}
