bsp_tree.h

/*************************************************************************/
/*  bsp_tree.h                                                           */
/*************************************************************************/
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/* Copyright (c) 2007-2016 Juan Linietsky, Ariel Manzur.                 */
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#ifndef BSP_TREE_H
#define BSP_TREE_H

#include "plane.h"
#include "aabb.h"
#include "face3.h"
#include "vector.h"
#include "dvector.h"

#include "variant.h"
class BSP_Tree {
public:

    enum {

        UNDER_LEAF=0xFFFF,
        OVER_LEAF=0xFFFE,
        MAX_NODES=0xFFFE,
        MAX_PLANES=(1<<16)
    };

    struct Node {

        uint16_t plane;
        uint16_t under;
        uint16_t over;
    };


private:
    // thanks to the properties of Vector,
    // this class can be assigned and passed around between threads
    // with no cost.

    Vector<Node> nodes;
    Vector<Plane> planes;
    AABB aabb;
    float error_radius;

    int _get_points_inside(int p_node,const Vector3* p_points,int *p_indices, const Vector3& p_center,const Vector3& p_half_extents,int p_indices_count) const;

    template<class T>
    bool _test_convex(const Node* p_nodes, const Plane* p_planes,int p_current, const T& p_convex) const;

public:

    bool is_empty() const { return nodes.size()==0; }
    Vector<Node> get_nodes() const;
    Vector<Plane> get_planes() const;
    AABB get_aabb() const;

    bool point_is_inside(const Vector3& p_point) const;
    int get_points_inside(const Vector3* p_points, int p_point_count) const;
    template<class T>
    bool convex_is_inside(const T& p_convex) const;

    operator Variant() const;

    void from_aabb(const AABB& p_aabb);

    BSP_Tree();
    BSP_Tree(const Variant& p_variant);
    BSP_Tree(const DVector<Face3>& p_faces,float p_error_radius=0);
    BSP_Tree(const Vector<Node> &p_nodes, const Vector<Plane> &p_planes, const AABB& p_aabb,float p_error_radius=0);
    ~BSP_Tree();

};

template<class T>
bool BSP_Tree::_test_convex(const Node* p_nodes, const Plane* p_planes,int p_current, const T& p_convex) const {

    if (p_current==UNDER_LEAF)
        return true;
    else if (p_current==OVER_LEAF)
        return false;

    bool collided=false;
    const Node&n=p_nodes[p_current];

    const Plane& p=p_planes[n.plane];

    float min,max;
    p_convex.project_range(p.normal,min,max);

    bool go_under = min < p.d;
    bool go_over = max >= p.d;

    if (go_under && _test_convex(p_nodes,p_planes,n.under,p_convex))
        collided=true;
    if (go_over && _test_convex(p_nodes,p_planes,n.over,p_convex))
        collided=true;

    return collided;

}

template<class T>
bool BSP_Tree::convex_is_inside(const T& p_convex) const {

    int node_count = nodes.size();
    if (node_count==0)
        return false;
    const Node* nodes=&this->nodes[0];
    const Plane* planes = &this->planes[0];

    return _test_convex(nodes,planes,node_count-1,p_convex);
}


#endif