#ifndef COLLISION_H
#define COLLISION_H

#include "vector.h"
#include "coordinates.h"
#include <stdlib.h>
#include <stdio.h>
#include <strings.h>

typedef struct CC_Tree
{
  unsigned long n;
  union
  {
  struct CC_Tree** b;
  unsigned long ID;
  } data;
  float r;
  Vector m;
} CC_Tree;

class CollisionCluster {
  
  CC_Tree* root;
  
  
 public:
  CollisionCluster (float r, Vector m); // simple cluster
  CollisionCluster (char* filename); // get cluster from file
  ~CollisionCluster ();
  
  int store (char* filename);
  
  friend bool cctree_trace( const Placement* p, CC_Tree* t, unsigned long* hitflags, const Line* trace, Vector* impactpoint);
  friend bool cctree_iterate(const Placement* pa, CC_Tree* ta, unsigned long* ahitflags, const Placement* pb, CC_Tree* tb, unsigned long* bhitflags);
  friend bool check_trace (const Placement* pa, const CollisionCluster* a, unsigned long* ahitflags, const Line* trace, Vector* impactpoint);
  friend bool check_collision (const Placement* pa, const CollisionCluster* a, unsigned long* ahitflags, const Placement* pb, const CollisionCluster* b, unsigned long* bhitflags);
};

bool sphere_sphere_collision( Vector m1, float r1, Vector m2, float r2);
bool trace_sphere_collision( Vector m, float r, const Line* l, Vector* impactpoint);

void setflag( unsigned long* flags, unsigned long ID);

void free_CC_Tree( CC_Tree* tree);
CC_Tree* load_CC_Tree (FILE* stream);
int save_CC_Tree (CC_Tree* tree, FILE* stream);

#endif