blender/extern/carve/lib/octree.cpp

// Begin License:
// Copyright (C) 2006-2011 Tobias Sargeant (tobias.sargeant@gmail.com).
// All rights reserved.
//
// This file is part of the Carve CSG Library (http://carve-csg.com/)
//
// This file may be used under the terms of the GNU General Public
// License version 2.0 as published by the Free Software Foundation
// and appearing in the file LICENSE.GPL2 included in the packaging of
// this file.
//
// This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
// INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE.
// End:


#if defined(HAVE_CONFIG_H)
#  include <carve_config.h>
#endif

#include <carve/octree_decl.hpp>
#include <carve/octree_impl.hpp>

#include <carve/poly_decl.hpp>

namespace carve {
  namespace csg {

    Octree::Node::Node(const carve::geom3d::Vector &newMin, const carve::geom3d::Vector &newMax) :
      parent(NULL), is_leaf(true), min(newMin), max(newMax) {
      for (int i = 0; i < 8; ++i) children[i] = NULL;
      aabb = Octree::makeAABB(this);
    }

    Octree::Node::Node(Node *p, double x1, double y1, double z1, double x2, double y2, double z2) :
      parent(p), is_leaf(true), min(carve::geom::VECTOR(x1, y1, z1)), max(carve::geom::VECTOR(x2, y2, z2)) {
      for (int i = 0; i < 8; ++i) children[i] = NULL;
      aabb = Octree::makeAABB(this);
    }

    Octree::Node::~Node() {
      for (int i = 0; i < 8; ++i) {
        if (children[i] != NULL) {
          (*children[i]).~Node();
        }
      }
      if (children[0] != NULL) {
        char *ptr = (char*)children[0];
        delete[] ptr;
      }
    }

    bool Octree::Node::mightContain(const carve::poly::Face<3> &face) {
      if (face.nVertices() == 3) {
        return aabb.intersects(carve::geom::tri<3>(face.vertex(0)->v, face.vertex(1)->v, face.vertex(2)->v));
      } else {
        return aabb.intersects(face.aabb) && aabb.intersects(face.plane_eqn);
      }
    }

    bool Octree::Node::mightContain(const carve::poly::Edge<3> &edge) {
      return aabb.intersectsLineSegment(edge.v1->v, edge.v2->v);
    }

    bool Octree::Node::mightContain(const carve::poly::Vertex<3> &p) {
      return aabb.containsPoint(p.v);
    }

    bool Octree::Node::hasChildren() {
      return !is_leaf;
    }

    bool Octree::Node::split() {
      if (is_leaf && hasGeometry()) {

        carve::geom3d::Vector mid = 0.5 * (min + max);
        char *ptr = new char[sizeof(Node)*8];
        children[0] = new (ptr + sizeof(Node) * 0) Node(this, min.x, min.y, min.z, mid.x, mid.y, mid.z);
        children[1] = new (ptr + sizeof(Node) * 1) Node(this, mid.x, min.y, min.z, max.x, mid.y, mid.z);
        children[2] = new (ptr + sizeof(Node) * 2) Node(this, min.x, mid.y, min.z, mid.x, max.y, mid.z);
        children[3] = new (ptr + sizeof(Node) * 3) Node(this, mid.x, mid.y, min.z, max.x, max.y, mid.z);
        children[4] = new (ptr + sizeof(Node) * 4) Node(this, min.x, min.y, mid.z, mid.x, mid.y, max.z);
        children[5] = new (ptr + sizeof(Node) * 5) Node(this, mid.x, min.y, mid.z, max.x, mid.y, max.z);
        children[6] = new (ptr + sizeof(Node) * 6) Node(this, min.x, mid.y, mid.z, mid.x, max.y, max.z);
        children[7] = new (ptr + sizeof(Node) * 7) Node(this, mid.x, mid.y, mid.z, max.x, max.y, max.z);

        for (int i = 0; i < 8; ++i) {
          putInside(faces, children[i], children[i]->faces);
          putInside(edges, children[i], children[i]->edges);
          putInside(vertices, children[i], children[i]->vertices);
        }

        faces.clear();
        edges.clear();
        vertices.clear();
        is_leaf = false;
      }
      return is_leaf;
    }

    template <class T>
    void Octree::Node::putInside(const T &input, Node *child, T &output) {
      for (typename T::const_iterator it = input.begin(), e = input.end(); it != e; ++it) {
        if (child->mightContain(**it)) {
          output.push_back(*it);
        }
      }
    }

    bool Octree::Node::hasGeometry() {
      return faces.size() > 0 || edges.size() > 0 || vertices.size() > 0;
    }

    Octree::Octree() {
      root = NULL;
    }

    Octree::~Octree() {
      if (root) delete root;
    }

    void Octree::setBounds(const carve::geom3d::Vector &min, const carve::geom3d::Vector &max) {
      if (root) delete root;
      root = new Node(min, max);
    }

    void Octree::setBounds(carve::geom3d::AABB aabb) {
      if (root) delete root;
      aabb.extent = 1.1 * aabb.extent;
      root = new Node(aabb.min(), aabb.max());
    }

    void Octree::addEdges(const std::vector<carve::poly::Edge<3> > &e) {
      root->edges.reserve(root->edges.size() + e.size());
      for (size_t i = 0; i < e.size(); ++i) {
        root->edges.push_back(&e[i]);
      }
    }

    void Octree::addFaces(const std::vector<carve::poly::Face<3> > &f) {
      root->faces.reserve(root->faces.size() + f.size());
      for (size_t i = 0; i < f.size(); ++i) {
        root->faces.push_back(&f[i]);
      } 
    }
    
    void Octree::addVertices(const std::vector<const carve::poly::Vertex<3> *> &p) {
      root->vertices.insert(root->vertices.end(), p.begin(), p.end());
    }

    carve::geom3d::AABB Octree::makeAABB(const Node *node) {
      carve::geom3d::Vector centre = 0.5 * (node->min + node->max);
      carve::geom3d::Vector size = SLACK_FACTOR * 0.5 * (node->max - node->min);
      return carve::geom3d::AABB(centre, size);
    }

    void Octree::doFindEdges(const carve::geom::aabb<3> &aabb,
                             Node *node,
                             std::vector<const carve::poly::Edge<3> *> &out,
                             unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.intersects(aabb)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindEdges(aabb, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->edges.size() > EDGE_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindEdges(aabb, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Edge<3>*>::const_iterator it = node->edges.begin(), e = node->edges.end(); it != e; ++it) {
            if ((*it)->tag_once()) {
              out.push_back(*it);
            }
          }
        }
      }
    }

    void Octree::doFindEdges(const carve::geom3d::LineSegment &l,
                             Node *node,
                             std::vector<const carve::poly::Edge<3> *> &out,
                             unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.intersectsLineSegment(l.v1, l.v2)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindEdges(l, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->edges.size() > EDGE_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindEdges(l, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Edge<3>*>::const_iterator it = node->edges.begin(), e = node->edges.end(); it != e; ++it) {
            if ((*it)->tag_once()) {
              out.push_back(*it);
            }
          }
        }
      }
    }

    void Octree::doFindEdges(const carve::geom3d::Vector &v,
                             Node *node,
                             std::vector<const carve::poly::Edge<3> *> &out,
                             unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.containsPoint(v)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindEdges(v, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->edges.size() > EDGE_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindEdges(v, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Edge<3>*>::const_iterator
                 it = node->edges.begin(), e = node->edges.end(); it != e; ++it) {
            if ((*it)->tag_once()) {
              out.push_back(*it);
            }
          }
        }
      }
    }

    void Octree::doFindFaces(const carve::geom::aabb<3> &aabb,
                             Node *node,
                             std::vector<const carve::poly::Face<3>*> &out,
                             unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.intersects(aabb)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindFaces(aabb, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->faces.size() > FACE_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindFaces(aabb, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Face<3>*>::const_iterator it = node->faces.begin(), e = node->faces.end(); it != e; ++it) {
            if ((*it)->tag_once()) {
              out.push_back(*it);
            }
          }
        }
      }
    }

    void Octree::doFindFaces(const carve::geom3d::LineSegment &l,
                             Node *node,
                             std::vector<const carve::poly::Face<3>*> &out,
                             unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.intersectsLineSegment(l.v1, l.v2)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindFaces(l, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->faces.size() > FACE_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindFaces(l, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Face<3>*>::const_iterator it = node->faces.begin(), e = node->faces.end(); it != e; ++it) {
            if ((*it)->tag_once()) {
              out.push_back(*it);
            }
          }
        }
      }
    }

    void Octree::doFindVerticesAllowDupes(const carve::geom3d::Vector &v, Node *node, std::vector<const carve::poly::Vertex<3> *> &out, unsigned depth) const {
      if (node == NULL) {
        return;
      }

      if (node->aabb.containsPoint(v)) {
        if (node->hasChildren()) {
          for (int i = 0; i < 8; ++i) {
            doFindVerticesAllowDupes(v, node->children[i], out, depth + 1);
          }
        } else {
          if (depth < MAX_SPLIT_DEPTH && node->vertices.size() > POINT_SPLIT_THRESHOLD) {
            if (!node->split()) {
              for (int i = 0; i < 8; ++i) {
                doFindVerticesAllowDupes(v, node->children[i], out, depth + 1);
              }
              return;
            }
          }
          for (std::vector<const carve::poly::Vertex<3> *>::const_iterator it = node->vertices.begin(), e = node->vertices.end(); it != e; ++it) {
            out.push_back(*it);
          }
        }
      }
    }

    void Octree::findEdgesNear(const carve::geom::aabb<3> &aabb, std::vector<const carve::poly::Edge<3>*> &out) const {
      tagable::tag_begin();
      doFindEdges(aabb, root, out, 0);
    }

    void Octree::findEdgesNear(const carve::geom3d::LineSegment &l, std::vector<const carve::poly::Edge<3>*> &out) const {
      tagable::tag_begin();
      doFindEdges(l, root, out, 0);
    }

    void Octree::findEdgesNear(const carve::poly::Edge<3> &e, std::vector<const carve::poly::Edge<3>*> &out) const {
      tagable::tag_begin();
      doFindEdges(carve::geom3d::LineSegment(e.v1->v, e.v2->v), root, out, 0);
    }

    void Octree::findEdgesNear(const carve::geom3d::Vector &v, std::vector<const carve::poly::Edge<3>*> &out) const {
      tagable::tag_begin();
      doFindEdges(v, root, out, 0);
    }

    void Octree::findFacesNear(const carve::geom::aabb<3> &aabb, std::vector<const carve::poly::Face<3>*> &out) const {
      tagable::tag_begin();
      doFindFaces(aabb, root, out, 0);
    }

    void Octree::findFacesNear(const carve::geom3d::LineSegment &l, std::vector<const carve::poly::Face<3>*> &out) const {
      tagable::tag_begin();
      doFindFaces(l, root, out, 0);
    }

    void Octree::findFacesNear(const carve::poly::Edge<3> &e, std::vector<const carve::poly::Face<3>*> &out) const {
      tagable::tag_begin();
      doFindFaces(carve::geom3d::LineSegment(e.v1->v, e.v2->v), root, out, 0);
    }

    void Octree::findVerticesNearAllowDupes(const carve::geom3d::Vector &v, std::vector<const carve::poly::Vertex<3> *> &out) const {
      tagable::tag_begin();
      doFindVerticesAllowDupes(v, root, out, 0);
    }

    void Octree::doSplit(int maxSplit, Node *node) {
      // Don't split down any further than 4 levels.
      if (maxSplit <= 0 || (node->edges.size() < 5 && node->faces.size() < 5)) {
        return;
      }

      if (!node->split()) {
        for (int i = 0; i < 8; ++i) {
          doSplit(maxSplit - 1, node->children[i]);
        }
      }
    }

    void Octree::splitTree() {
      // initially split 4 levels
      doSplit(0, root);
    }

  }
}