| //##################################################################### |
| // Copyright 2003, 2004, Zhaosheng Bao, Ronald Fedkiw, Eran Guendelman, Andrew Selle. |
| // This file is part of PhysBAM whose distribution is governed by the license contained in the accompanying file PHYSBAM_COPYRIGHT.txt. |
| //##################################################################### |
| // Class SEGMENT_2D |
| //##################################################################### |
| #ifndef __SEGMENT_2D__ |
| #define __SEGMENT_2D__ |
| #include "../Matrices_And_Vectors/VECTOR_2D.h" |
| |
| namespace PhysBAM |
| { |
| |
| template<class T> class RAY_2D; |
| template<class T> class ORIENTED_BOX_2D; |
| |
| template<class T> |
| class SEGMENT_2D |
| { |
| public: |
| VECTOR_2D<T> x1, x2; |
| enum POINT_SEGMENT_COLLISION_TYPE {POINT_SEGMENT_NO_COLLISION, POINT_SEGMENT_COLLISION_ENDS_OUTSIDE, POINT_SEGMENT_COLLISION_ENDS_INSIDE, |
| POINT_SEGMENT_UNKNOWN_COLLISION |
| }; |
| |
| SEGMENT_2D() |
| : x1 (0, 0), x2 (1, 0) |
| {} |
| |
| SEGMENT_2D (const VECTOR_2D<T>& x1_input, const VECTOR_2D<T>& x2_input) |
| : x1 (x1_input), x2 (x2_input) |
| {} |
| |
| T Length() const |
| { |
| return (x2 - x1).Magnitude(); |
| } |
| |
| VECTOR_2D<T> Center() const |
| { |
| return (T).5 * (x1 + x2); |
| } |
| |
| static VECTOR_2D<T> Clockwise_Normal (const VECTOR_2D<T>& x1, const VECTOR_2D<T>& x2) |
| { |
| return (x2 - x1).Normalized().Rotate_Clockwise_90(); |
| } |
| |
| static VECTOR_2D<T> Robust_Clockwise_Normal (const VECTOR_2D<T>& x1, const VECTOR_2D<T>& x2, const T tolerance = 1e-8) |
| { |
| return (x2 - x1).Robust_Normalized (tolerance).Rotate_Clockwise_90(); |
| } |
| |
| VECTOR_2D<T> Clockwise_Normal() const |
| { |
| return SEGMENT_2D<T>::Clockwise_Normal (x1, x2); |
| } |
| |
| static VECTOR_2D<T> Barycentric_Coordinates (const VECTOR_2D<T>& location, const VECTOR_2D<T>& x1, const VECTOR_2D<T>& x2) |
| { |
| VECTOR_2D<T> v = x2 - x1; |
| T denominator = VECTOR_2D<T>::Dot_Product (v, v); |
| |
| if (denominator == 0) return VECTOR_2D<T> (1, 0); // x1 and x2 are a single point |
| else |
| { |
| T t = VECTOR_2D<T>::Dot_Product (location - x1, v) / denominator; |
| return VECTOR_2D<T> (1 - t, t); |
| } |
| } |
| |
| VECTOR_2D<T> Barycentric_Coordinates (const VECTOR_2D<T>& location) const |
| { |
| return Barycentric_Coordinates (location, x1, x2); |
| } |
| |
| static VECTOR_2D<T> Point_From_Barycentric_Coordinates (const T alpha, const VECTOR_2D<T>& x1, const VECTOR_2D<T>& x2) |
| { |
| return (x2 - x1) * alpha + x1; |
| } |
| |
| VECTOR_2D<T> Point_From_Barycentric_Coordinates (const T alpha) const |
| { |
| return (x2 - x1) * alpha + x1; |
| } |
| |
| //##################################################################### |
| bool Segment_Line_Intersection (const VECTOR_2D<T>& point_on_line, const VECTOR_2D<T>& normal_of_line, T &interpolation_fraction) const; |
| VECTOR_2D<T> Closest_Point_On_Segment (const VECTOR_2D<T>& point) const; |
| T Distance_From_Point_To_Segment (const VECTOR_2D<T>& point) const; |
| VECTOR_2D<T> Closest_Point_On_Line (const VECTOR_2D<T>& point) const; |
| T Distance_From_Point_To_Line (const VECTOR_2D<T>& point) const; |
| VECTOR_2D<T> Shortest_Vector_Between_Segments (const SEGMENT_2D<T>& segment, T& a, T& b) const; |
| int Segment_Segment_Interaction (const SEGMENT_2D<T>& segment, const VECTOR_2D<T>& v1, const VECTOR_2D<T>& v2, const VECTOR_2D<T>& v3, const VECTOR_2D<T>& v4, |
| const T interaction_distance, T& distance, VECTOR_2D<T>& normal, T& a, T& b, T& relative_speed, const T small_number = 0) const; |
| // int Segment_Segment_Collision(const SEGMENT_2D<T>& segment,const VECTOR_2D<T>& v1,const VECTOR_2D<T>& v2,const VECTOR_2D<T>& v3,const VECTOR_2D<T>& v4,const T dt, |
| // const T collision_thickness,T& collision_time,VECTOR_2D<T>& normal,T& a,T& b,T& relative_speed,const T small_number=0) const; |
| ORIENTED_BOX_2D<T> Thickened_Oriented_Box (const T thickness_over_two = 0) const; |
| bool Intersection (RAY_2D<T>& ray, const T thickness_over_two) const; |
| static bool Intersection_X_Segment (RAY_2D<T>& ray, const T x1, const T x2, const T y, const T thickness_over_two); |
| static bool Intersection_Y_Segment (RAY_2D<T>& ray, const T x, const T y1, const T y2, const T thickness_over_two); |
| bool Fuzzy_Intersection (RAY_2D<T>& ray, const T thickness_over_two = 0) const; |
| bool Inside (const VECTOR_2D<T>& point, const T thickness_over_two = 0) const; |
| bool Closest_Non_Intersecting_Point (RAY_2D<T>& ray, const T thickness_over_two) const; |
| static POINT_SEGMENT_COLLISION_TYPE Robust_Point_Segment_Collision (const SEGMENT_2D<T>& initial_segment, const SEGMENT_2D<T>& final_segment, const VECTOR_2D<T>& x, |
| const VECTOR_2D<T>& final_x, const T dt, const T collision_thickness, T& collision_time, T& collision_alpha); |
| bool Segment_Point_Collision (const VECTOR_2D<T>& x, const VECTOR_2D<T>& v, const VECTOR_2D<T>& v1, const VECTOR_2D<T>& v2, const T dt, const T collision_thickness, T& collision_time, T& collision_alpha) const; |
| //##################################################################### |
| }; |
| |
| template<class T> std::ostream &operator<< (std::ostream &output, const SEGMENT_2D<T> &segment) |
| { |
| output << segment.x1 << ", " << segment.x2; |
| return output; |
| } |
| |
| } |
| #endif |
| |
