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/** \author Jia Pan */

#ifndef HPP_FCL_TRAVERSAL_NODE_OCTREE_H
#define HPP_FCL_TRAVERSAL_NODE_OCTREE_H

/// @cond INTERNAL

#include <hpp/fcl/collision_data.h>
#include <hpp/fcl/internal/traversal_node_base.h>
#include <hpp/fcl/narrowphase/narrowphase.h>
#include <hpp/fcl/octree.h>
#include <hpp/fcl/BVH/BVH_model.h>
#include <hpp/fcl/shape/geometric_shapes_utility.h>

namespace hpp
{
namespace fcl
{

/// @brief Algorithms for collision related with octree
class HPP_FCL_DLLAPI OcTreeSolver
{
private:
  const GJKSolver* solver;

  mutable const CollisionRequest* crequest;
  mutable const DistanceRequest* drequest;

  mutable CollisionResult* cresult;
  mutable DistanceResult* dresult;

public:
  OcTreeSolver(const GJKSolver* solver_) : solver(solver_),
                                                   crequest(NULL),
                                                   drequest(NULL),
                                                   cresult(NULL),
                                                   dresult(NULL)
  {
  }

  /// @brief collision between two octrees
  void OcTreeIntersect(const OcTree* tree1, const OcTree* tree2,
                       const Transform3f& tf1, const Transform3f& tf2,
                       const CollisionRequest& request_,
                       CollisionResult& result_) const
  {
    crequest = &request_;
    cresult = &result_;
    
    OcTreeIntersectRecurse(tree1, tree1->getRoot(), tree1->getRootBV(), 
                           tree2, tree2->getRoot(), tree2->getRootBV(), 
                           tf1, tf2);
  }

  /// @brief distance between two octrees
  void OcTreeDistance(const OcTree* tree1, const OcTree* tree2,
                      const Transform3f& tf1, const Transform3f& tf2,
                      const DistanceRequest& request_,
                      DistanceResult& result_) const
  {
    drequest = &request_;
    dresult = &result_;

    OcTreeDistanceRecurse(tree1, tree1->getRoot(), tree1->getRootBV(), 
                          tree2, tree2->getRoot(), tree2->getRootBV(),
                          tf1, tf2);
  }

  /// @brief collision between octree and mesh
  template<typename BV>
  void OcTreeMeshIntersect(const OcTree* tree1, const BVHModel<BV>* tree2,
                           const Transform3f& tf1, const Transform3f& tf2,
                           const CollisionRequest& request_,
                           CollisionResult& result_) const
  {
    crequest = &request_;
    cresult = &result_;

    OcTreeMeshIntersectRecurse(tree1, tree1->getRoot(), tree1->getRootBV(),
                               tree2, 0,
                               tf1, tf2);
  }

  /// @brief distance between octree and mesh
  template<typename BV>
  void OcTreeMeshDistance(const OcTree* tree1, const BVHModel<BV>* tree2,
                          const Transform3f& tf1, const Transform3f& tf2,
                          const DistanceRequest& request_,
                          DistanceResult& result_) const
  {
    drequest = &request_;
    dresult = &result_;

    OcTreeMeshDistanceRecurse(tree1, tree1->getRoot(), tree1->getRootBV(),
                              tree2, 0,
                              tf1, tf2);
  }

  /// @brief collision between mesh and octree
  template<typename BV>
  void MeshOcTreeIntersect(const BVHModel<BV>* tree1, const OcTree* tree2,
                           const Transform3f& tf1, const Transform3f& tf2,
                           const CollisionRequest& request_,
                           CollisionResult& result_) const
  
  {
    crequest = &request_;
    cresult = &result_;

    OcTreeMeshIntersectRecurse(tree2, tree2->getRoot(), tree2->getRootBV(),
                               tree1, 0,
                               tf2, tf1);
  }

  /// @brief distance between mesh and octree
  template<typename BV>
  void MeshOcTreeDistance(const BVHModel<BV>* tree1, const OcTree* tree2,
                          const Transform3f& tf1, const Transform3f& tf2,
                          const DistanceRequest& request_,
                          DistanceResult& result_) const
  {
    drequest = &request_;
    dresult = &result_;

    OcTreeMeshDistanceRecurse(tree1, 0,
                              tree2, tree2->getRoot(), tree2->getRootBV(),
                              tf1, tf2);
  }

  /// @brief collision between octree and shape
  template<typename S>
  void OcTreeShapeIntersect(const OcTree* tree, const S& s,
                            const Transform3f& tf1, const Transform3f& tf2,
                            const CollisionRequest& request_,
                            CollisionResult& result_) const
  {
    crequest = &request_;
    cresult = &result_;

    AABB bv2;
    computeBV<AABB>(s, Transform3f(), bv2);
    OBB obb2;
    convertBV(bv2, tf2, obb2);
    OcTreeShapeIntersectRecurse(tree, tree->getRoot(), tree->getRootBV(),
                                s, obb2,
                                tf1, tf2);
    
  }

  /// @brief collision between shape and octree
  template<typename S>
  void ShapeOcTreeIntersect(const S& s, const OcTree* tree,
                            const Transform3f& tf1, const Transform3f& tf2,
                            const CollisionRequest& request_,
                            CollisionResult& result_) const
  {
    crequest = &request_;
    cresult = &result_;

    AABB bv1;
    computeBV<AABB>(s, Transform3f(), bv1);
    OBB obb1;
    convertBV(bv1, tf1, obb1);
    OcTreeShapeIntersectRecurse(tree, tree->getRoot(), tree->getRootBV(),
                                s, obb1,
                                tf2, tf1);
  }

  /// @brief distance between octree and shape
  template<typename S>
  void OcTreeShapeDistance(const OcTree* tree, const S& s,
                           const Transform3f& tf1, const Transform3f& tf2,
                           const DistanceRequest& request_,
                           DistanceResult& result_) const
  {
    drequest = &request_;
    dresult = &result_;

    AABB aabb2;
    computeBV<AABB>(s, tf2, aabb2);
    OcTreeShapeDistanceRecurse(tree, tree->getRoot(), tree->getRootBV(),
                               s, aabb2,
                               tf1, tf2);
  }

  /// @brief distance between shape and octree
  template<typename S>
  void ShapeOcTreeDistance(const S& s, const OcTree* tree,
                           const Transform3f& tf1, const Transform3f& tf2,
                           const DistanceRequest& request_,
                           DistanceResult& result_) const
  {
    drequest = &request_;
    dresult = &result_;

    AABB aabb1;
    computeBV<AABB>(s, tf1, aabb1);
    OcTreeShapeDistanceRecurse(tree, tree->getRoot(), tree->getRootBV(),
                               s, aabb1,
                               tf2, tf1);
  }
  

private:
  template<typename S>
  bool OcTreeShapeDistanceRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                                  const S& s, const AABB& aabb2,
                                  const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!tree1->nodeHasChildren(root1))
    {
      if(tree1->isNodeOccupied(root1))
      {
        Box box;
        Transform3f box_tf;
        constructBox(bv1, tf1, box, box_tf);
 
        FCL_REAL dist;
        Vec3f closest_p1, closest_p2, normal;
        solver->shapeDistance(box, box_tf, s, tf2, dist, closest_p1,
                              closest_p2, normal);
        
        dresult->update(dist, tree1, &s, (int) (root1 - tree1->getRoot()),
                        DistanceResult::NONE, closest_p1, closest_p2,
                        normal);
        
        return drequest->isSatisfied(*dresult);
      }
      else
        return false;
    }

    if(!tree1->isNodeOccupied(root1)) return false;
    
    for(unsigned int i = 0; i < 8; ++i)
    {
      if(tree1->nodeChildExists(root1, i))
      {
        const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
        AABB child_bv;
        computeChildBV(bv1, i, child_bv);
        
        AABB aabb1;
        convertBV(child_bv, tf1, aabb1);
        FCL_REAL d = aabb1.distance(aabb2);
        if(d < dresult->min_distance)
        {
          if(OcTreeShapeDistanceRecurse(tree1, child, child_bv, s, aabb2, tf1, tf2))
            return true;
        }        
      }
    }

    return false;
  }

  template<typename S>
  bool OcTreeShapeIntersectRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                                   const S& s, const OBB& obb2,
                                   const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!root1)
    {
      OBB obb1;
      convertBV(bv1, tf1, obb1);
      if(obb1.overlap(obb2))
      {
        Box box;
        Transform3f box_tf;
        constructBox(bv1, tf1, box, box_tf);

        FCL_REAL distance;
        if(solver->shapeIntersect(box, box_tf, s, tf2, distance, false, NULL, NULL))
        {
          AABB overlap_part;
          AABB aabb1, aabb2;
          computeBV<AABB, Box>(box, box_tf, aabb1);
          computeBV<AABB, S>(s, tf2, aabb2);
          aabb1.overlap(aabb2, overlap_part);
        }
      }

      return false;
    }
    else if(!tree1->nodeHasChildren(root1))
    {
      if(tree1->isNodeOccupied(root1)) // occupied area
      {
        OBB obb1;
        convertBV(bv1, tf1, obb1);
        if(obb1.overlap(obb2))
        {
          Box box;
          Transform3f box_tf;
          constructBox(bv1, tf1, box, box_tf);

          FCL_REAL distance;
          if(!crequest->enable_contact)
          {
            if(solver->shapeIntersect(box, box_tf, s, tf2, distance, false, NULL, NULL))
            {
              if(cresult->numContacts() < crequest->num_max_contacts)
                cresult->addContact(Contact(tree1, &s, static_cast<int>(root1 - tree1->getRoot()), Contact::NONE));
            }
          }
          else
          {
            Vec3f contact;
            Vec3f normal;

            if(solver->shapeIntersect(box, box_tf, s, tf2, distance, true, &contact, &normal))
            {
              if(cresult->numContacts() < crequest->num_max_contacts)
                cresult->addContact(Contact(tree1, &s, static_cast<int>(root1 - tree1->getRoot()), Contact::NONE, contact, normal, distance));
            }
          }

          return crequest->isSatisfied(*cresult);
        }
        else return false;
      }
      else // free area
        return false;
    }

    /// stop when 1) bounding boxes of two objects not overlap; OR
    ///           2) at least of one the nodes is free; OR
    ///           2) (two uncertain nodes or one node occupied and one node uncertain) AND cost not required
    if(tree1->isNodeFree(root1)) return false;
    else if((tree1->isNodeUncertain(root1) || s.isUncertain())) return false;
    else
    {
      OBB obb1;
      convertBV(bv1, tf1, obb1);
      if(!obb1.overlap(obb2)) return false;
    }

    for(unsigned int i = 0; i < 8; ++i)
    {
      if(tree1->nodeChildExists(root1, i))
      {
        const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
        AABB child_bv;
        computeChildBV(bv1, i, child_bv);
        
        if(OcTreeShapeIntersectRecurse(tree1, child, child_bv, s, obb2, tf1, tf2))
          return true;
      }
    }

    return false;    
  }

  template<typename BV>
  bool OcTreeMeshDistanceRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                                 const BVHModel<BV>* tree2, unsigned int root2,
                                 const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!tree1->nodeHasChildren(root1) && tree2->getBV(root2).isLeaf())
    {
      if(tree1->isNodeOccupied(root1))
      {
        Box box;
        Transform3f box_tf;
        constructBox(bv1, tf1, box, box_tf);

        int primitive_id = tree2->getBV(root2).primitiveId();
        const Triangle& tri_id = tree2->tri_indices[primitive_id];
        const Vec3f& p1 = tree2->vertices[tri_id[0]];
        const Vec3f& p2 = tree2->vertices[tri_id[1]];
        const Vec3f& p3 = tree2->vertices[tri_id[2]];
        
        FCL_REAL dist;
        Vec3f closest_p1, closest_p2, normal;
        solver->shapeTriangleInteraction(box, box_tf, p1, p2, p3, tf2, dist,
                                         closest_p1, closest_p2, normal);

        dresult->update(dist, tree1, tree2, (int) (root1 - tree1->getRoot()),
                        primitive_id, closest_p1, closest_p2, normal);

        return drequest->isSatisfied(*dresult);
      }
      else
        return false;
    }

    if(!tree1->isNodeOccupied(root1)) return false;

    if(tree2->getBV(root2).isLeaf() || (tree1->nodeHasChildren(root1) && (bv1.size() > tree2->getBV(root2).bv.size())))
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree1->nodeChildExists(root1, i))
        {
          const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
          AABB child_bv;
          computeChildBV(bv1, i, child_bv);

          FCL_REAL d;
          AABB aabb1, aabb2;
          convertBV(child_bv, tf1, aabb1);
          convertBV(tree2->getBV(root2).bv, tf2, aabb2);
          d = aabb1.distance(aabb2);
          
          if(d < dresult->min_distance)
          {
            if(OcTreeMeshDistanceRecurse(tree1, child, child_bv, tree2, root2, tf1, tf2))
              return true;
          }
        }
      }
    }
    else
    {
      FCL_REAL d;
      AABB aabb1, aabb2;
      convertBV(bv1, tf1, aabb1);
      unsigned int child = (unsigned int)tree2->getBV(root2).leftChild();
      convertBV(tree2->getBV(child).bv, tf2, aabb2);
      d = aabb1.distance(aabb2);

      if(d < dresult->min_distance)
      {
        if(OcTreeMeshDistanceRecurse(tree1, root1, bv1, tree2, child, tf1, tf2))
          return true;
      }

      child = (unsigned int)tree2->getBV(root2).rightChild();
      convertBV(tree2->getBV(child).bv, tf2, aabb2);
      d = aabb1.distance(aabb2);
      
      if(d < dresult->min_distance)
      {
        if(OcTreeMeshDistanceRecurse(tree1, root1, bv1, tree2, child, tf1, tf2))
          return true;      
      }
    }

    return false;
  }


  template<typename BV>
  bool OcTreeMeshIntersectRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                                  const BVHModel<BV>* tree2, unsigned int root2,
                                  const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!root1)
    {
      if(tree2->getBV(root2).isLeaf())
      {
        OBB obb1, obb2;
        convertBV(bv1, tf1, obb1);
        convertBV(tree2->getBV(root2).bv, tf2, obb2);
        if(obb1.overlap(obb2))
        {
          Box box;
          Transform3f box_tf;
          constructBox(bv1, tf1, box, box_tf);

          int primitive_id = tree2->getBV(root2).primitiveId();
          const Triangle& tri_id = tree2->tri_indices[primitive_id];
          const Vec3f& p1 = tree2->vertices[tri_id[0]];
          const Vec3f& p2 = tree2->vertices[tri_id[1]];
          const Vec3f& p3 = tree2->vertices[tri_id[2]];
          Vec3f c1, c2, normal;
          FCL_REAL distance;
          if(solver->shapeTriangleInteraction
             (box, box_tf, p1, p2, p3, tf2, distance, c1, c2, normal))
          {
            AABB overlap_part;
            AABB aabb1;
            computeBV<AABB, Box>(box, box_tf, aabb1);
            AABB aabb2(tf2.transform(p1), tf2.transform(p2), tf2.transform(p3));
            aabb1.overlap(aabb2, overlap_part);
          }
        }

        return false;
      }
      else
      {
        if(OcTreeMeshIntersectRecurse(tree1, root1, bv1, tree2, (unsigned int)tree2->getBV(root2).leftChild(), tf1, tf2))
          return true;

        if(OcTreeMeshIntersectRecurse(tree1, root1, bv1, tree2, (unsigned int)tree2->getBV(root2).rightChild(), tf1, tf2))
          return true;

        return false;
      }
    }
    else if(!tree1->nodeHasChildren(root1) && tree2->getBV(root2).isLeaf())
    {
      if(tree1->isNodeOccupied(root1))
      {
        OBB obb1, obb2;
        convertBV(bv1, tf1, obb1);
        convertBV(tree2->getBV(root2).bv, tf2, obb2);
        if(obb1.overlap(obb2))
        {
          Box box;
          Transform3f box_tf;
          constructBox(bv1, tf1, box, box_tf);

          int primitive_id = tree2->getBV(root2).primitiveId();
          const Triangle& tri_id = tree2->tri_indices[primitive_id];
          const Vec3f& p1 = tree2->vertices[tri_id[0]];
          const Vec3f& p2 = tree2->vertices[tri_id[1]];
          const Vec3f& p3 = tree2->vertices[tri_id[2]];
        
          if(!crequest->enable_contact)
          {
            Vec3f c1, c2, normal;
            FCL_REAL distance;
            if(solver->shapeTriangleInteraction
               (box, box_tf, p1, p2, p3, tf2, distance, c1, c2, normal))
            {
              if(cresult->numContacts() < crequest->num_max_contacts)
                cresult->addContact(Contact(tree1, tree2,
                                            (int)(root1 - tree1->getRoot()),
                                            primitive_id));
            }
          }
          else
          {
            Vec3f c1, c2;
            FCL_REAL distance;
            Vec3f normal;

            if(solver->shapeTriangleInteraction(box, box_tf, p1, p2, p3, tf2,
                                                distance, c1, c2, normal))
            {
              assert (crequest->security_margin == 0);
              if(cresult->numContacts() < crequest->num_max_contacts)
                cresult->addContact
                  (Contact(tree1, tree2, (int) (root1 - tree1->getRoot()),
                           primitive_id, c1, normal, -distance));
            }
          }

          return crequest->isSatisfied(*cresult);
        }
        else
          return false;
      }
      else // free area
        return false;
    }

    /// stop when 1) bounding boxes of two objects not overlap; OR
    ///           2) at least one of the nodes is free; OR
    ///           2) (two uncertain nodes OR one node occupied and one node uncertain) AND cost not required
    if(tree1->isNodeFree(root1)) return false;
    else if((tree1->isNodeUncertain(root1) || tree2->isUncertain()))
      return false;
    else
    {
      OBB obb1, obb2;
      convertBV(bv1, tf1, obb1);
      convertBV(tree2->getBV(root2).bv, tf2, obb2);
      if(!obb1.overlap(obb2)) return false;      
    }
   
    if(tree2->getBV(root2).isLeaf() || (tree1->nodeHasChildren(root1) && (bv1.size() > tree2->getBV(root2).bv.size())))
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree1->nodeChildExists(root1, i))
        {
          const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
          AABB child_bv;
          computeChildBV(bv1, i, child_bv);
          
          if(OcTreeMeshIntersectRecurse(tree1, child, child_bv, tree2, root2, tf1, tf2))
            return true;
        }
      }
    }
    else
    {
      if(OcTreeMeshIntersectRecurse(tree1, root1, bv1, tree2, (unsigned int)tree2->getBV(root2).leftChild(), tf1, tf2))
        return true;

      if(OcTreeMeshIntersectRecurse(tree1, root1, bv1, tree2, (unsigned int)tree2->getBV(root2).rightChild(), tf1, tf2))
        return true;      

    }

    return false;
  }

  bool OcTreeDistanceRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                             const OcTree* tree2, const OcTree::OcTreeNode* root2, const AABB& bv2,
                             const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!tree1->nodeHasChildren(root1) && !tree2->nodeHasChildren(root2))
    {
      if(tree1->isNodeOccupied(root1) && tree2->isNodeOccupied(root2))
      {
        Box box1, box2;
        Transform3f box1_tf, box2_tf;
        constructBox(bv1, tf1, box1, box1_tf);
        constructBox(bv2, tf2, box2, box2_tf);

        FCL_REAL dist;
        Vec3f closest_p1, closest_p2, normal;
        solver->shapeDistance(box1, box1_tf, box2, box2_tf, dist, closest_p1,
                              closest_p2, normal);

        dresult->update(dist, tree1, tree2, (int) (root1 - tree1->getRoot()),
                        (int) (root2 - tree2->getRoot()),
                        closest_p1, closest_p2, normal);
        
        return drequest->isSatisfied(*dresult);
      }
      else
        return false;
    }

    if(!tree1->isNodeOccupied(root1) || !tree2->isNodeOccupied(root2)) return false;

    if(!tree2->nodeHasChildren(root2) || (tree1->nodeHasChildren(root1) && (bv1.size() > bv2.size())))
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree1->nodeChildExists(root1, i))
        {
          const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
          AABB child_bv;
          computeChildBV(bv1, i, child_bv);

          FCL_REAL d;
          AABB aabb1, aabb2;
          convertBV(bv1, tf1, aabb1);
          convertBV(bv2, tf2, aabb2);
          d = aabb1.distance(aabb2);

          if(d < dresult->min_distance)
          {
          
            if(OcTreeDistanceRecurse(tree1, child, child_bv, tree2, root2, bv2, tf1, tf2))
              return true;
          }
        }
      }
    }
    else
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree2->nodeChildExists(root2, i))
        {
          const OcTree::OcTreeNode* child = tree2->getNodeChild(root2, i);
          AABB child_bv;
          computeChildBV(bv2, i, child_bv);

          FCL_REAL d;
          AABB aabb1, aabb2;
          convertBV(bv1, tf1, aabb1);
          convertBV(bv2, tf2, aabb2);
          d = aabb1.distance(aabb2);

          if(d < dresult->min_distance)
          {
            if(OcTreeDistanceRecurse(tree1, root1, bv1, tree2, child, child_bv, tf1, tf2))
              return true;
          }
        }
      }
    }
    
    return false;
  }


  bool OcTreeIntersectRecurse(const OcTree* tree1, const OcTree::OcTreeNode* root1, const AABB& bv1,
                              const OcTree* tree2, const OcTree::OcTreeNode* root2, const AABB& bv2,
                              const Transform3f& tf1, const Transform3f& tf2) const
  {
    if(!root1 && !root2)
    {
      OBB obb1, obb2;
      convertBV(bv1, tf1, obb1);
      convertBV(bv2, tf2, obb2);

      if(obb1.overlap(obb2))
      {
        Box box1, box2;
        Transform3f box1_tf, box2_tf;
        constructBox(bv1, tf1, box1, box1_tf);
        constructBox(bv2, tf2, box2, box2_tf);
        
        AABB overlap_part;
        AABB aabb1, aabb2;
        computeBV<AABB, Box>(box1, box1_tf, aabb1);
        computeBV<AABB, Box>(box2, box2_tf, aabb2);
        aabb1.overlap(aabb2, overlap_part);
      }

      return false;
    }
    else if(!root1 && root2)
    {
      if(tree2->nodeHasChildren(root2))
      {
        for(unsigned int i = 0; i < 8; ++i)
        {
          if(tree2->nodeChildExists(root2, i))
          {
            const OcTree::OcTreeNode* child = tree2->getNodeChild(root2, i);
            AABB child_bv;
            computeChildBV(bv2, i, child_bv);
            if(OcTreeIntersectRecurse(tree1, NULL, bv1, tree2, child, child_bv, tf1, tf2))
              return true;
          }
          else 
          {
            AABB child_bv;
            computeChildBV(bv2, i, child_bv);
            if(OcTreeIntersectRecurse(tree1, NULL, bv1, tree2, NULL, child_bv, tf1, tf2))
              return true;
          }
        }
      }
      else
      {
        if(OcTreeIntersectRecurse(tree1, NULL, bv1, tree2, NULL, bv2, tf1, tf2))
          return true;
      }
      
      return false;
    }
    else if(root1 && !root2)
    {
      if(tree1->nodeHasChildren(root1))
      {
        for(unsigned int i = 0; i < 8; ++i)
        {
          if(tree1->nodeChildExists(root1, i))
          {
            const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
            AABB child_bv;
            computeChildBV(bv1, i,  child_bv);
            if(OcTreeIntersectRecurse(tree1, child, child_bv, tree2, NULL, bv2, tf1, tf2))
              return true;
          }
          else
          {
            AABB child_bv;
            computeChildBV(bv1, i, child_bv);
            if(OcTreeIntersectRecurse(tree1, NULL, child_bv, tree2, NULL, bv2, tf1, tf2))
              return true;
          }
        }
      }
      else
      {
        if(OcTreeIntersectRecurse(tree1, NULL, bv1, tree2, NULL, bv2, tf1, tf2))
          return true;
      }
      
      return false;
    }
    else if(!tree1->nodeHasChildren(root1) && !tree2->nodeHasChildren(root2))
    {
      if(tree1->isNodeOccupied(root1) && tree2->isNodeOccupied(root2)) // occupied area
      {
        if(!crequest->enable_contact)
        {
          OBB obb1, obb2;
          convertBV(bv1, tf1, obb1);
          convertBV(bv2, tf2, obb2);
          
          if(obb1.overlap(obb2))
          {
            if(cresult->numContacts() < crequest->num_max_contacts)
              cresult->addContact(Contact(tree1, tree2, static_cast<int>(root1 - tree1->getRoot()), static_cast<int>(root2 - tree2->getRoot())));
          }
        }
        else
        {
          Box box1, box2;
          Transform3f box1_tf, box2_tf;
          constructBox(bv1, tf1, box1, box1_tf);
          constructBox(bv2, tf2, box2, box2_tf);

          Vec3f contact;
          FCL_REAL distance;
          Vec3f normal;
          if(solver->shapeIntersect(box1, box1_tf, box2, box2_tf, distance, true, &contact, &normal))
          {
            if(cresult->numContacts() < crequest->num_max_contacts)
              cresult->addContact(Contact(tree1, tree2, static_cast<int>(root1 - tree1->getRoot()), static_cast<int>(root2 - tree2->getRoot()), contact, normal, distance));
          }
        }

        return crequest->isSatisfied(*cresult);
      }
      else // free area (at least one node is free)
        return false;
    }

    /// stop when 1) bounding boxes of two objects not overlap; OR
    ///           2) at least one of the nodes is free; OR
    ///           2) (two uncertain nodes OR one node occupied and one node uncertain) AND cost not required
    if(tree1->isNodeFree(root1) || tree2->isNodeFree(root2)) return false;
    else if((tree1->isNodeUncertain(root1) || tree2->isNodeUncertain(root2)))
      return false;
    else 
    {
      OBB obb1, obb2;
      convertBV(bv1, tf1, obb1);
      convertBV(bv2, tf2, obb2);
      if(!obb1.overlap(obb2)) return false;
    }

    if(!tree2->nodeHasChildren(root2) || (tree1->nodeHasChildren(root1) && (bv1.size() > bv2.size())))
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree1->nodeChildExists(root1, i))
        {
          const OcTree::OcTreeNode* child = tree1->getNodeChild(root1, i);
          AABB child_bv;
          computeChildBV(bv1, i, child_bv);
        
          if(OcTreeIntersectRecurse(tree1, child, child_bv, 
                                    tree2, root2, bv2,
                                    tf1, tf2))
            return true;
        }
      }
    }
    else
    {
      for(unsigned int i = 0; i < 8; ++i)
      {
        if(tree2->nodeChildExists(root2, i))
        {
          const OcTree::OcTreeNode* child = tree2->getNodeChild(root2, i);
          AABB child_bv;
          computeChildBV(bv2, i, child_bv);
          
          if(OcTreeIntersectRecurse(tree1, root1, bv1,
                                    tree2, child, child_bv,
                                    tf1, tf2))
            return true;
        }
      }
    }

    return false;
  }
};

/// @addtogroup Traversal_For_Collision
/// @{

/// @brief Traversal node for octree collision
class HPP_FCL_DLLAPI OcTreeCollisionTraversalNode : public CollisionTraversalNodeBase
{
public:
  OcTreeCollisionTraversalNode(const CollisionRequest& request) :
  CollisionTraversalNodeBase (request)
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }

  bool BVDisjoints(unsigned int, unsigned) const
  {
    return false;
  }

  bool BVDisjoints(unsigned, unsigned, FCL_REAL&) const
  {
    return false;
  }

  void leafCollides(unsigned, unsigned, FCL_REAL&) const
  {
    otsolver->OcTreeIntersect(model1, model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const OcTree* model2;

  Transform3f tf1, tf2;

  const OcTreeSolver* otsolver;
};

/// @brief Traversal node for shape-octree collision
template<typename S>
class HPP_FCL_DLLAPI ShapeOcTreeCollisionTraversalNode : public CollisionTraversalNodeBase
{
public:
 ShapeOcTreeCollisionTraversalNode(const CollisionRequest& request) :
  CollisionTraversalNodeBase (request)
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }

  bool BVDisjoints(unsigned int, unsigned int) const
  {
    return false;
  }

  bool BVDisjoints(unsigned int, unsigned int, FCL_REAL&) const
  {
    return false;
  }

  void leafCollides(unsigned int, unsigned int, FCL_REAL&) const
  {
    otsolver->OcTreeShapeIntersect(model2, *model1, tf2, tf1, request, *result);
  }

  const S* model1;
  const OcTree* model2;

  Transform3f tf1, tf2;

  const OcTreeSolver* otsolver;
};

/// @brief Traversal node for octree-shape collision

template<typename S>
class HPP_FCL_DLLAPI OcTreeShapeCollisionTraversalNode : public CollisionTraversalNodeBase
{
public:
 OcTreeShapeCollisionTraversalNode(const CollisionRequest& request) :
  CollisionTraversalNodeBase (request)
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }

  bool BVDisjoints(unsigned int, unsigned int) const
  {
    return false;
  }

  bool BVDisjoints(unsigned int, unsigned int, fcl::FCL_REAL&) const
  {
    return false;
  }

  void leafCollides(unsigned int, unsigned int, FCL_REAL&) const
  {
    otsolver->OcTreeShapeIntersect(model1, *model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const S* model2;

  Transform3f tf1, tf2;
 
  const OcTreeSolver* otsolver;  
};

/// @brief Traversal node for mesh-octree collision
template<typename BV>
class HPP_FCL_DLLAPI MeshOcTreeCollisionTraversalNode : public CollisionTraversalNodeBase
{
public:
 MeshOcTreeCollisionTraversalNode(const CollisionRequest& request) :
  CollisionTraversalNodeBase (request)
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }

  bool BVDisjoints(unsigned int, unsigned int) const
  {
    return false;
  }

  bool BVDisjoints(unsigned int, unsigned int, FCL_REAL&) const
  {
    return false;
  }

  void leafCollides(unsigned int, unsigned int, FCL_REAL&) const
  {
    otsolver->OcTreeMeshIntersect(model2, model1, tf2, tf1, request, *result);
  }

  const BVHModel<BV>* model1;
  const OcTree* model2;

  Transform3f tf1, tf2;
    
  const OcTreeSolver* otsolver;
};

/// @brief Traversal node for octree-mesh collision
template<typename BV>
class HPP_FCL_DLLAPI OcTreeMeshCollisionTraversalNode : public CollisionTraversalNodeBase
{
public:
 OcTreeMeshCollisionTraversalNode(const CollisionRequest& request) :
  CollisionTraversalNodeBase (request)
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }

  bool BVDisjoints(unsigned int, unsigned int) const
  {
    return false;
  }

  bool BVDisjoints(unsigned int, unsigned int, FCL_REAL&) const
  {
    return false;
  }

  void leafCollides(unsigned int, unsigned int, FCL_REAL&) const
  {
    otsolver->OcTreeMeshIntersect(model1, model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const BVHModel<BV>* model2;

  Transform3f tf1, tf2;
    
  const OcTreeSolver* otsolver;
};

/// @}

/// @addtogroup Traversal_For_Distance
/// @{

/// @brief Traversal node for octree distance
class HPP_FCL_DLLAPI OcTreeDistanceTraversalNode : public DistanceTraversalNodeBase
{
public:
  OcTreeDistanceTraversalNode()
  {
    model1 = NULL;
    model2 = NULL;

    otsolver = NULL;
  }


  FCL_REAL BVDistanceLowerBound(unsigned, unsigned) const
  {
    return -1;
  }

  bool BVDistanceLowerBound(unsigned, unsigned, FCL_REAL&) const
  {
    return false;
  }

  void leafComputeDistance(unsigned, unsigned int) const
  {
    otsolver->OcTreeDistance(model1, model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const OcTree* model2;

  const OcTreeSolver* otsolver;
};



/// @brief Traversal node for shape-octree distance
template<typename S>
class HPP_FCL_DLLAPI ShapeOcTreeDistanceTraversalNode : public DistanceTraversalNodeBase
{
public:
  ShapeOcTreeDistanceTraversalNode()
  {
    model1 = NULL;
    model2 = NULL;
    
    otsolver = NULL;
  }

  FCL_REAL BVDistanceLowerBound(unsigned int, unsigned int) const
  {
    return -1;
  }

  void leafComputeDistance(unsigned int, unsigned int) const
  {
    otsolver->OcTreeShapeDistance(model2, *model1, tf2, tf1, request, *result);
  }

  const S* model1;
  const OcTree* model2;

  const OcTreeSolver* otsolver;
};

/// @brief Traversal node for octree-shape distance
template<typename S>
class HPP_FCL_DLLAPI OcTreeShapeDistanceTraversalNode : public DistanceTraversalNodeBase
{
public:
  OcTreeShapeDistanceTraversalNode()
  {
    model1 = NULL;
    model2 = NULL;
    
    otsolver = NULL;
  }

  FCL_REAL BVDistanceLowerBound(unsigned int, unsigned int) const
  {
    return -1;
  }

  void leafComputeDistance(unsigned int, unsigned int) const
  {
    otsolver->OcTreeShapeDistance(model1, *model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const S* model2;

  const OcTreeSolver* otsolver;
};

/// @brief Traversal node for mesh-octree distance
template<typename BV>
class HPP_FCL_DLLAPI MeshOcTreeDistanceTraversalNode : public DistanceTraversalNodeBase
{
public:
  MeshOcTreeDistanceTraversalNode()
  {
    model1 = NULL;
    model2 = NULL;
    
    otsolver = NULL;
  }

  FCL_REAL BVDistanceLowerBound(unsigned int, unsigned int) const
  {
    return -1;
  }

  void leafComputeDistance(unsigned int, unsigned int) const
  {
    otsolver->OcTreeMeshDistance(model2, model1, tf2, tf1, request, *result);
  }

  const BVHModel<BV>* model1;
  const OcTree* model2;

  const OcTreeSolver* otsolver;

};

/// @brief Traversal node for octree-mesh distance
template<typename BV>
class HPP_FCL_DLLAPI OcTreeMeshDistanceTraversalNode : public DistanceTraversalNodeBase
{
public:
  OcTreeMeshDistanceTraversalNode()
  {
    model1 = NULL;
    model2 = NULL;
    
    otsolver = NULL;
  }

  FCL_REAL BVDistanceLowerBound(unsigned int, unsigned int) const
  {
    return -1;
  }

  void leafComputeDistance(unsigned int, unsigned int) const
  {
    otsolver->OcTreeMeshDistance(model1, model2, tf1, tf2, request, *result);
  }

  const OcTree* model1;
  const BVHModel<BV>* model2;

  const OcTreeSolver* otsolver;

};

/// @}

}

} // namespace hpp

/// @endcond

#endif
