/* SPDX-FileCopyrightText: 2011-2023 Blender Authors
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

#include "octree.h"
#include "Queue.h"

#include <Eigen/Dense>
#include <algorithm>
#include <ctime>

/**
 * Implementations of Octree member functions.
 *
 * @author Tao Ju
 */

/* set to non-zero value to enable debugging output */
#define DC_DEBUG 0

#if DC_DEBUG
/* enable debug printfs */
#  define dc_printf printf
#else
/* disable debug printfs */
#  define dc_printf(...) \
    do { \
    } while (0)
#endif

Octree::Octree(ModelReader *mr,
               DualConAllocOutput alloc_output_func,
               DualConAddVert add_vert_func,
               DualConAddQuad add_quad_func,
               DualConFlags flags,
               DualConMode dualcon_mode,
               int depth,
               float threshold,
               float sharpness)
    : use_flood_fill(flags & DUALCON_FLOOD_FILL),
      /* note on `use_manifold':

     After playing around with this option, the only case I could
     find where this option gives different results is on
     relatively thin corners. Sometimes along these corners two
     vertices from separate sides will be placed in the same
     position, so hole gets filled with a 5-sided face, where two
     of those vertices are in the same 3D location. If
     `use_manifold' is disabled, then the modifier doesn't
     generate two separate vertices so the results end up as all
     quads.

     Since the results are just as good with all quads, there
     doesn't seem any reason to allow this to be toggled in
     Blender. -nicholasbishop
   */
      use_manifold(false),
      hermite_num(sharpness),
      mode(dualcon_mode),
      alloc_output(alloc_output_func),
      add_vert(add_vert_func),
      add_quad(add_quad_func)
{
  thresh = threshold;
  reader = mr;
  dimen = 1 << GRID_DIMENSION;
  range = reader->getBoundingBox(origin);
  nodeCount = nodeSpace = 0;
  maxDepth = depth;
  mindimen = (dimen >> maxDepth);
  minshift = (GRID_DIMENSION - maxDepth);
  buildTable();

  maxTrianglePerCell = 0;

  // Initialize memory
#ifdef IN_VERBOSE_MODE
  dc_printf("Range: %f origin: %f, %f,%f \n", range, origin[0], origin[1], origin[2]);
  dc_printf("Initialize memory...\n");
#endif
  initMemory();
  root = (Node *)createInternal(0);

  // Read MC table
#ifdef IN_VERBOSE_MODE
  dc_printf("Reading contour table...\n");
#endif
  cubes = new Cubes();
}

Octree::~Octree()
{
  delete cubes;
  freeMemory();
}

void Octree::scanConvert()
{
  // Scan triangles
#if DC_DEBUG
  clock_t start, finish;
  start = clock();
#endif

  addAllTriangles();
  resetMinimalEdges();
  preparePrimalEdgesMask(&root->internal);

#if DC_DEBUG
  finish = clock();
  dc_printf("Time taken: %f seconds                   \n",
            (double)(finish - start) / CLOCKS_PER_SEC);
#endif

  // Generate signs
  // Find holes
#if DC_DEBUG
  dc_printf("Patching...\n");
  start = clock();
#endif
  trace();
#if DC_DEBUG
  finish = clock();
  dc_printf("Time taken: %f seconds \n", (double)(finish - start) / CLOCKS_PER_SEC);
#  ifdef IN_VERBOSE_MODE
  dc_printf("Holes: %d Average Length: %f Max Length: %d \n",
            numRings,
            (float)totRingLengths / (float)numRings,
            maxRingLength);
#  endif
#endif

  // Check again
  int tnumRings = numRings;
  trace();
#ifdef IN_VERBOSE_MODE
  dc_printf("Holes after patching: %d \n", numRings);
#endif
  numRings = tnumRings;

#if DC_DEBUG
  dc_printf("Building signs...\n");
  start = clock();
#endif
  buildSigns();
#if DC_DEBUG
  finish = clock();
  dc_printf("Time taken: %f seconds \n", (double)(finish - start) / CLOCKS_PER_SEC);
#endif

  if (use_flood_fill) {
    /*
       start = clock();
       floodFill();
       // Check again
       tnumRings = numRings;
       trace();
       dc_printf("Holes after filling: %d \n", numRings);
       numRings = tnumRings;
       buildSigns();
       finish = clock();
       dc_printf("Time taken: %f seconds \n",   (double)(finish - start) / CLOCKS_PER_SEC);
     */
#if DC_DEBUG
    start = clock();
    dc_printf("Removing components...\n");
#endif
    floodFill();
    buildSigns();
    //  dc_printf("Checking...\n");
    //  floodFill();
#if DC_DEBUG
    finish = clock();
    dc_printf("Time taken: %f seconds \n", (double)(finish - start) / CLOCKS_PER_SEC);
#endif
  }

  // Output
#if DC_DEBUG
  start = clock();
#endif
  writeOut();
#if DC_DEBUG
  finish = clock();
#endif
  // dc_printf("Time taken: %f seconds \n",   (double)(finish - start) / CLOCKS_PER_SEC);

  // Print info
#ifdef IN_VERBOSE_MODE
  printMemUsage();
#endif
}

void Octree::initMemory()
{
  leafalloc[0] = new MemoryAllocator<sizeof(LeafNode)>();
  leafalloc[1] = new MemoryAllocator<sizeof(LeafNode) + sizeof(float) * EDGE_FLOATS>();
  leafalloc[2] = new MemoryAllocator<sizeof(LeafNode) + sizeof(float) * EDGE_FLOATS * 2>();
  leafalloc[3] = new MemoryAllocator<sizeof(LeafNode) + sizeof(float) * EDGE_FLOATS * 3>();

  alloc[0] = new MemoryAllocator<sizeof(InternalNode)>();
  alloc[1] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *)>();
  alloc[2] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 2>();
  alloc[3] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 3>();
  alloc[4] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 4>();
  alloc[5] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 5>();
  alloc[6] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 6>();
  alloc[7] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 7>();
  alloc[8] = new MemoryAllocator<sizeof(InternalNode) + sizeof(Node *) * 8>();
}

void Octree::freeMemory()
{
  for (int i = 0; i < 9; i++) {
    alloc[i]->destroy();
    delete alloc[i];
  }

  for (int i = 0; i < 4; i++) {
    leafalloc[i]->destroy();
    delete leafalloc[i];
  }
}

void Octree::printMemUsage()
{
  int totalbytes = 0;
  dc_printf("********* Internal nodes: \n");
  for (int i = 0; i < 9; i++) {
    alloc[i]->printInfo();

    totalbytes += alloc[i]->getAll() * alloc[i]->getBytes();
  }
  dc_printf("********* Leaf nodes: \n");
  int totalLeafs = 0;
  for (int i = 0; i < 4; i++) {
    leafalloc[i]->printInfo();

    totalbytes += leafalloc[i]->getAll() * leafalloc[i]->getBytes();
    totalLeafs += leafalloc[i]->getAllocated();
  }

  dc_printf("Total allocated bytes on disk: %d \n", totalbytes);
  dc_printf("Total leaf nodes: %d\n", totalLeafs);

  /* Unused when not debuggining. */
  (void)totalbytes;
  (void)totalLeafs;
}

void Octree::resetMinimalEdges()
{
  cellProcParity(root, 0, maxDepth);
}

void Octree::addAllTriangles()
{
  Triangle *trian;
  int count = 0;

#if DC_DEBUG
  int total = reader->getNumTriangles();
  int unitcount = 1000;
  dc_printf("\nScan converting to depth %d...\n", maxDepth);
#endif

  srand(0);

  while ((trian = reader->getNextTriangle()) != nullptr) {
    // Drop triangles
    {
      addTriangle(trian, count);
    }
    delete trian;

    count++;

#if DC_DEBUG
    if (count % unitcount == 0) {
      putchar(13);

      switch ((count / unitcount) % 4) {
        case 0:
          dc_printf("-");
          break;
        case 1:
          dc_printf("/");
          break;
        case 2:
          dc_printf("|");
          break;
        case 3:
          dc_printf("\\");
          break;
      }

      float percent = (float)count / total;

      /*
         int totbars = 50;
         int bars =(int)(percent * totbars);
         for(int i = 0; i < bars; i ++) {
          putchar(219);
         }
         for(i = bars; i < totbars; i ++) {
          putchar(176);
         }
       */

      dc_printf(" %d triangles: ", count);
      dc_printf(" %f%% complete.", 100 * percent);
    }
#endif
  }
  putchar(13);
}

/* Prepare a triangle for insertion into the octree; call the other
   addTriangle() to (recursively) build the octree */
void Octree::addTriangle(Triangle *trian, int triind)
{
  int i, j;

  /* Project the triangle's coordinates into the grid */
  for (i = 0; i < 3; i++) {
    for (j = 0; j < 3; j++) {
      trian->vt[i][j] = dimen * (trian->vt[i][j] - origin[j]) / range;
    }
  }

  /* Generate projections */
  int64_t cube[2][3] = {{0, 0, 0}, {dimen, dimen, dimen}};
  int64_t trig[3][3];
  for (i = 0; i < 3; i++) {
    for (j = 0; j < 3; j++) {
      trig[i][j] = (int64_t)(trian->vt[i][j]);
    }
  }

  /* Add triangle to the octree */
  int64_t errorvec = (int64_t)(0);
  CubeTriangleIsect *proj = new CubeTriangleIsect(cube, trig, errorvec, triind);
  root = (Node *)addTriangle(&root->internal, proj, maxDepth);

  delete proj->inherit;
  delete proj;
}

#if 0
static void print_depth(int height, int maxDepth)
{
  for (int i = 0; i < maxDepth - height; i++) {
    printf("  ");
  }
}
#endif

InternalNode *Octree::addTriangle(InternalNode *node, CubeTriangleIsect *p, int height)
{
  int i;
  const int vertdiff[8][3] = {
      {0, 0, 0}, {0, 0, 1}, {0, 1, -1}, {0, 0, 1}, {1, -1, -1}, {0, 0, 1}, {0, 1, -1}, {0, 0, 1}};
  unsigned char boxmask = p->getBoxMask();
  CubeTriangleIsect *subp = new CubeTriangleIsect(p);

  int count = 0;
  int tempdiff[3] = {0, 0, 0};

  /* Check triangle against each of the input node's children */
  for (i = 0; i < 8; i++) {
    tempdiff[0] += vertdiff[i][0];
    tempdiff[1] += vertdiff[i][1];
    tempdiff[2] += vertdiff[i][2];

    /* Quick pruning using bounding box */
    if (boxmask & (1 << i)) {
      subp->shift(tempdiff);
      tempdiff[0] = tempdiff[1] = tempdiff[2] = 0;

      /* Pruning using intersection test */
      if (subp->isIntersecting()) {
        if (!node->has_child(i)) {
          if (height == 1) {
            node = addLeafChild(node, i, count, createLeaf(0));
          }
          else {
            node = addInternalChild(node, i, count, createInternal(0));
          }
        }
        Node *chd = node->get_child(count);

        if (node->is_child_leaf(i)) {
          node->set_child(count, (Node *)updateCell(&chd->leaf, subp));
        }
        else {
          node->set_child(count, (Node *)addTriangle(&chd->internal, subp, height - 1));
        }
      }
    }

    if (node->has_child(i)) {
      count++;
    }
  }

  delete subp;

  return node;
}

LeafNode *Octree::updateCell(LeafNode *node, CubeTriangleIsect *p)
{
  int i;

  // Edge connectivity
  int mask[3] = {0, 4, 8};
  int oldc = 0, newc = 0;
  float offs[3];
  float a[3], b[3], c[3];

  for (i = 0; i < 3; i++) {
    if (!getEdgeParity(node, mask[i])) {
      if (p->isIntersectingPrimary(i)) {
        // actualQuads ++;
        setEdge(node, mask[i]);
        offs[newc] = p->getIntersectionPrimary(i);
        a[newc] = (float)p->inherit->norm[0];
        b[newc] = (float)p->inherit->norm[1];
        c[newc] = (float)p->inherit->norm[2];
        newc++;
      }
    }
    else {
      offs[newc] = getEdgeOffsetNormal(node, oldc, a[newc], b[newc], c[newc]);

      oldc++;
      newc++;
    }
  }

  if (newc > oldc) {
    // New offsets added, update this node
    node = updateEdgeOffsetsNormals(node, oldc, newc, offs, a, b, c);
  }

  return node;
}

void Octree::preparePrimalEdgesMask(InternalNode *node)
{
  int count = 0;
  for (int i = 0; i < 8; i++) {
    if (node->has_child(i)) {
      if (node->is_child_leaf(i)) {
        createPrimalEdgesMask(&node->get_child(count)->leaf);
      }
      else {
        preparePrimalEdgesMask(&node->get_child(count)->internal);
      }

      count++;
    }
  }
}

void Octree::trace()
{
  int st[3] = {
      0,
      0,
      0,
  };
  numRings = 0;
  totRingLengths = 0;
  maxRingLength = 0;

  PathList *chdpath = nullptr;
  root = trace(root, st, dimen, maxDepth, chdpath);

  if (chdpath != nullptr) {
    dc_printf("there are incomplete rings.\n");
    printPaths(chdpath);
  }
}

Node *Octree::trace(Node *newnode, int *st, int len, int depth, PathList *&paths)
{
  len >>= 1;
  PathList *chdpaths[8];
  Node *chd[8];
  int nst[8][3];
  int i, j;

  // Get children paths
  int chdleaf[8];
  newnode->internal.fill_children(chd, chdleaf);

  // int count = 0;
  for (i = 0; i < 8; i++) {
    for (j = 0; j < 3; j++) {
      nst[i][j] = st[j] + len * vertmap[i][j];
    }

    if (chd[i] == nullptr || newnode->internal.is_child_leaf(i)) {
      chdpaths[i] = nullptr;
    }
    else {
      trace(chd[i], nst[i], len, depth - 1, chdpaths[i]);
    }
  }

  // Get connectors on the faces
  PathList *conn[12];
  Node *nf[2];
  int lf[2];
  int df[2] = {depth - 1, depth - 1};
  int *nstf[2];

  newnode->internal.fill_children(chd, chdleaf);

  for (i = 0; i < 12; i++) {
    int c[2] = {cellProcFaceMask[i][0], cellProcFaceMask[i][1]};

    for (int j = 0; j < 2; j++) {
      lf[j] = chdleaf[c[j]];
      nf[j] = chd[c[j]];
      nstf[j] = nst[c[j]];
    }

    conn[i] = nullptr;

    findPaths((Node **)nf, lf, df, nstf, depth - 1, cellProcFaceMask[i][2], conn[i]);

#if 0
    if (conn[i]) {
      printPath(conn[i]);
    }
#endif
  }

  // Connect paths
  PathList *rings = nullptr;
  combinePaths(chdpaths[0], chdpaths[1], conn[8], rings);
  combinePaths(chdpaths[2], chdpaths[3], conn[9], rings);
  combinePaths(chdpaths[4], chdpaths[5], conn[10], rings);
  combinePaths(chdpaths[6], chdpaths[7], conn[11], rings);

  combinePaths(chdpaths[0], chdpaths[2], conn[4], rings);
  combinePaths(chdpaths[4], chdpaths[6], conn[5], rings);
  combinePaths(chdpaths[0], nullptr, conn[6], rings);
  combinePaths(chdpaths[4], nullptr, conn[7], rings);

  combinePaths(chdpaths[0], chdpaths[4], conn[0], rings);
  combinePaths(chdpaths[0], nullptr, conn[1], rings);
  combinePaths(chdpaths[0], nullptr, conn[2], rings);
  combinePaths(chdpaths[0], nullptr, conn[3], rings);

  // By now, only chdpaths[0] and rings have contents

  // Process rings
  if (rings) {
    // printPath(rings);

    /* Let's count first */
    PathList *trings = rings;
    while (trings) {
      numRings++;
      totRingLengths += trings->length;
      maxRingLength = std::max(trings->length, maxRingLength);
      trings = trings->next;
    }

    // printPath(rings);
    newnode = patch(newnode, st, (len << 1), rings);
  }

  // Return incomplete paths
  paths = chdpaths[0];
  return newnode;
}

void Octree::findPaths(Node *node[2],
                       const int leaf[2],
                       const int depth[2],
                       int *st[2],
                       int maxdep,
                       int dir,
                       PathList *&paths)
{
  if (!(node[0] && node[1])) {
    return;
  }

  if (!(leaf[0] && leaf[1])) {
    // Not at the bottom, recur

    // Fill children nodes
    int i, j;
    Node *chd[2][8];
    int chdleaf[2][8];
    int nst[2][8][3];

    for (j = 0; j < 2; j++) {
      if (!leaf[j]) {
        node[j]->internal.fill_children(chd[j], chdleaf[j]);

        int len = (dimen >> (maxDepth - depth[j] + 1));
        for (i = 0; i < 8; i++) {
          for (int k = 0; k < 3; k++) {
            nst[j][i][k] = st[j][k] + len * vertmap[i][k];
          }
        }
      }
    }

    // 4 face calls
    Node *nf[2];
    int df[2];
    int lf[2];
    int *nstf[2];
    for (i = 0; i < 4; i++) {
      int c[2] = {faceProcFaceMask[dir][i][0], faceProcFaceMask[dir][i][1]};
      for (int j = 0; j < 2; j++) {
        if (leaf[j]) {
          lf[j] = leaf[j];
          nf[j] = node[j];
          df[j] = depth[j];
          nstf[j] = st[j];
        }
        else {
          lf[j] = chdleaf[j][c[j]];
          nf[j] = chd[j][c[j]];
          df[j] = depth[j] - 1;
          nstf[j] = nst[j][c[j]];
        }
      }
      findPaths(nf, lf, df, nstf, maxdep - 1, faceProcFaceMask[dir][i][2], paths);
    }
  }
  else {
    // At the bottom, check this face
    int ind = (depth[0] == maxdep ? 0 : 1);
    int fcind = 2 * dir + (1 - ind);
    if (getFaceParity((LeafNode *)node[ind], fcind)) {
      // Add into path
      PathElement *ele1 = new PathElement;
      PathElement *ele2 = new PathElement;

      ele1->pos[0] = st[0][0];
      ele1->pos[1] = st[0][1];
      ele1->pos[2] = st[0][2];

      ele2->pos[0] = st[1][0];
      ele2->pos[1] = st[1][1];
      ele2->pos[2] = st[1][2];

      ele1->next = ele2;
      ele2->next = nullptr;

      PathList *lst = new PathList;
      lst->head = ele1;
      lst->tail = ele2;
      lst->length = 2;
      lst->next = paths;
      paths = lst;

      // int l =(dimen >> maxDepth);
    }
  }
}

void Octree::combinePaths(PathList *&list1, PathList *list2, PathList *paths, PathList *&rings)
{
  // Make new list of paths
  PathList *nlist = nullptr;

  // Search for each connectors in paths
  PathList *tpaths = paths;
  PathList *tlist, *pre;
  while (tpaths) {
    PathList *singlist = tpaths;
    PathList *templist;
    tpaths = tpaths->next;
    singlist->next = nullptr;

    // Look for hookup in list1
    tlist = list1;
    pre = nullptr;
    while (tlist) {
      if ((templist = combineSinglePath(list1, pre, tlist, singlist, nullptr, singlist)) !=
          nullptr)
      {
        singlist = templist;
        continue;
      }
      pre = tlist;
      tlist = tlist->next;
    }

    // Look for hookup in list2
    tlist = list2;
    pre = nullptr;
    while (tlist) {
      if ((templist = combineSinglePath(list2, pre, tlist, singlist, nullptr, singlist)) !=
          nullptr)
      {
        singlist = templist;
        continue;
      }
      pre = tlist;
      tlist = tlist->next;
    }

    // Look for hookup in nlist
    tlist = nlist;
    pre = nullptr;
    while (tlist) {
      if ((templist = combineSinglePath(nlist, pre, tlist, singlist, nullptr, singlist)) !=
          nullptr)
      {
        singlist = templist;
        continue;
      }
      pre = tlist;
      tlist = tlist->next;
    }

    // Add to nlist or rings
    if (isEqual(singlist->head, singlist->tail)) {
      PathElement *temp = singlist->head;
      singlist->head = temp->next;
      delete temp;
      singlist->length--;
      singlist->tail->next = singlist->head;

      singlist->next = rings;
      rings = singlist;
    }
    else {
      singlist->next = nlist;
      nlist = singlist;
    }
  }

  // Append list2 and nlist to the end of list1
  tlist = list1;
  if (tlist != nullptr) {
    while (tlist->next != nullptr) {
      tlist = tlist->next;
    }
    tlist->next = list2;
  }
  else {
    tlist = list2;
    list1 = list2;
  }

  if (tlist != nullptr) {
    while (tlist->next != nullptr) {
      tlist = tlist->next;
    }
    tlist->next = nlist;
  }
  else {
    tlist = nlist;
    list1 = nlist;
  }
}

PathList *Octree::combineSinglePath(PathList *&head1,
                                    PathList *pre1,
                                    PathList *&list1,
                                    PathList *&head2,
                                    PathList *pre2,
                                    PathList *&list2)
{
  if (isEqual(list1->head, list2->head) || isEqual(list1->tail, list2->tail)) {
    // Reverse the list
    if (list1->length < list2->length) {
      // Reverse list1
      PathElement *prev = list1->head;
      PathElement *next = prev->next;
      prev->next = nullptr;
      while (next != nullptr) {
        PathElement *tnext = next->next;
        next->next = prev;

        prev = next;
        next = tnext;
      }

      list1->tail = list1->head;
      list1->head = prev;
    }
    else {
      // Reverse list2
      PathElement *prev = list2->head;
      PathElement *next = prev->next;
      prev->next = nullptr;
      while (next != nullptr) {
        PathElement *tnext = next->next;
        next->next = prev;

        prev = next;
        next = tnext;
      }

      list2->tail = list2->head;
      list2->head = prev;
    }
  }

  if (isEqual(list1->head, list2->tail)) {

    // Easy case
    PathElement *temp = list1->head->next;
    delete list1->head;
    list2->tail->next = temp;

    PathList *nlist = new PathList;
    nlist->length = list1->length + list2->length - 1;
    nlist->head = list2->head;
    nlist->tail = list1->tail;
    nlist->next = nullptr;

    deletePath(head1, pre1, list1);
    deletePath(head2, pre2, list2);

    return nlist;
  }
  if (isEqual(list1->tail, list2->head)) {
    // Easy case
    PathElement *temp = list2->head->next;
    delete list2->head;
    list1->tail->next = temp;

    PathList *nlist = new PathList;
    nlist->length = list1->length + list2->length - 1;
    nlist->head = list1->head;
    nlist->tail = list2->tail;
    nlist->next = nullptr;

    deletePath(head1, pre1, list1);
    deletePath(head2, pre2, list2);

    return nlist;
  }

  return nullptr;
}

void Octree::deletePath(PathList *&head, PathList *pre, PathList *&curr)
{
  PathList *temp = curr;
  curr = temp->next;
  delete temp;

  if (pre == nullptr) {
    head = curr;
  }
  else {
    pre->next = curr;
  }
}

void Octree::printElement(PathElement *ele)
{
  if (ele != nullptr) {
    dc_printf("(%d %d %d)", ele->pos[0], ele->pos[1], ele->pos[2]);
  }
}

void Octree::printPath(PathList *path)
{
  PathElement *n = path->head;
  int same = 0;

#if DC_DEBUG
  int len = (dimen >> maxDepth);
#endif
  while (n && (same == 0 || n != path->head)) {
    same++;
    dc_printf("(%d %d %d)", n->pos[0] / len, n->pos[1] / len, n->pos[2] / len);
    n = n->next;
  }

  if (n == path->head) {
    dc_printf(" Ring!\n");
  }
  else {
    dc_printf(" %p end!\n", n);
  }
}

void Octree::printPath(PathElement *path)
{
  PathElement *n = path;
  int same = 0;
#if DC_DEBUG
  int len = (dimen >> maxDepth);
#endif
  while (n && (same == 0 || n != path)) {
    same++;
    dc_printf("(%d %d %d)", n->pos[0] / len, n->pos[1] / len, n->pos[2] / len);
    n = n->next;
  }

  if (n == path) {
    dc_printf(" Ring!\n");
  }
  else {
    dc_printf(" %p end!\n", n);
  }
}

void Octree::printPaths(PathList *path)
{
  PathList *iter = path;
  while (iter != nullptr) {
    dc_printf("Path %d:\n", i);
    printPath(iter);
    iter = iter->next;
  }
}

Node *Octree::patch(Node *newnode, int st[3], int len, PathList *rings)
{
#ifdef IN_DEBUG_MODE
  dc_printf("Call to PATCH with rings: \n");
  printPaths(rings);
#endif

  /* Do nothing but couting
     PathList* tlist = rings;
     PathList* ttlist;
     PathElement* telem, * ttelem;
     while(tlist!= nullptr) {
      // printPath(tlist);
      numRings ++;
      totRingLengths += tlist->length;
      if(tlist->length > maxRingLength) {
          maxRingLength = tlist->length;
      }
      ttlist = tlist;
      tlist = tlist->next;
     }
     return node;
   */

  /* Pass onto separate calls in each direction */
  if (len == mindimen) {
    dc_printf("Error! should have no list by now.\n");
    exit(0);
  }

  // YZ plane
  PathList *xlists[2];
  newnode = patchSplit(newnode, st, len, rings, 0, xlists[0], xlists[1]);

  // XZ plane
  PathList *ylists[4];
  newnode = patchSplit(newnode, st, len, xlists[0], 1, ylists[0], ylists[1]);
  newnode = patchSplit(newnode, st, len, xlists[1], 1, ylists[2], ylists[3]);

  // XY plane
  PathList *zlists[8];
  newnode = patchSplit(newnode, st, len, ylists[0], 2, zlists[0], zlists[1]);
  newnode = patchSplit(newnode, st, len, ylists[1], 2, zlists[2], zlists[3]);
  newnode = patchSplit(newnode, st, len, ylists[2], 2, zlists[4], zlists[5]);
  newnode = patchSplit(newnode, st, len, ylists[3], 2, zlists[6], zlists[7]);

  // Recur
  len >>= 1;
  int count = 0;
  for (int i = 0; i < 8; i++) {
    if (zlists[i] != nullptr) {
      int nori[3] = {
          st[0] + len * vertmap[i][0], st[1] + len * vertmap[i][1], st[2] + len * vertmap[i][2]};
      patch(newnode->internal.get_child(count), nori, len, zlists[i]);
    }

    if (newnode->internal.has_child(i)) {
      count++;
    }
  }
#ifdef IN_DEBUG_MODE
  dc_printf("Return from PATCH\n");
#endif
  return newnode;
}

Node *Octree::patchSplit(Node *newnode,
                         int st[3],
                         int len,
                         PathList *rings,
                         int dir,
                         PathList *&nrings1,
                         PathList *&nrings2)
{
#ifdef IN_DEBUG_MODE
  dc_printf("Call to PATCHSPLIT with direction %d and rings: \n", dir);
  printPaths(rings);
#endif

  nrings1 = nullptr;
  nrings2 = nullptr;
  PathList *tmp;
  while (rings != nullptr) {
    // Process this ring
    newnode = patchSplitSingle(newnode, st, len, rings->head, dir, nrings1, nrings2);

    // Delete this ring from the group
    tmp = rings;
    rings = rings->next;
    delete tmp;
  }

#ifdef IN_DEBUG_MODE
  dc_printf("Return from PATCHSPLIT with \n");
  dc_printf("Rings gourp 1:\n");
  printPaths(nrings1);
  dc_printf("Rings group 2:\n");
  printPaths(nrings2);
#endif

  return newnode;
}

Node *Octree::patchSplitSingle(Node *newnode,
                               int st[3],
                               int len,
                               PathElement *head,
                               int dir,
                               PathList *&nrings1,
                               PathList *&nrings2)
{
#ifdef IN_DEBUG_MODE
  dc_printf("Call to PATCHSPLITSINGLE with direction %d and path: \n", dir);
  printPath(head);
#endif

  if (head == nullptr) {
#ifdef IN_DEBUG_MODE
    dc_printf("Return from PATCHSPLITSINGLE with head==nullptr.\n");
#endif
    return newnode;
  }

  // printPath(head);

  // Walk along the ring to find pair of intersections
  PathElement *pre1 = nullptr;
  PathElement *pre2 = nullptr;
  int side = findPair(head, st[dir] + len / 2, dir, pre1, pre2);

#if 0
  if (pre1 == pre2) {
    int edgelen = (dimen >> maxDepth);
    dc_printf("Location: %d %d %d Direction: %d Reso: %d\n",
              st[0] / edgelen,
              st[1] / edgelen,
              st[2] / edgelen,
              dir,
              len / edgelen);
    printPath(head);
    exit(0);
  }
#endif

  if (side) {
    // Entirely on one side
    PathList *nring = new PathList();
    nring->head = head;

    if (side == -1) {
      nring->next = nrings1;
      nrings1 = nring;
    }
    else {
      nring->next = nrings2;
      nrings2 = nring;
    }
  }
  else {
    // Break into two parts
    PathElement *nxt1 = pre1->next;
    PathElement *nxt2 = pre2->next;
    pre1->next = nxt2;
    pre2->next = nxt1;

    newnode = connectFace(newnode, st, len, dir, pre1, pre2);

    if (isEqual(pre1, pre1->next)) {
      if (pre1 == pre1->next) {
        delete pre1;
        pre1 = nullptr;
      }
      else {
        PathElement *temp = pre1->next;
        pre1->next = temp->next;
        delete temp;
      }
    }
    if (isEqual(pre2, pre2->next)) {
      if (pre2 == pre2->next) {
        delete pre2;
        pre2 = nullptr;
      }
      else {
        PathElement *temp = pre2->next;
        pre2->next = temp->next;
        delete temp;
      }
    }

    compressRing(pre1);
    compressRing(pre2);

    // Recur
    newnode = patchSplitSingle(newnode, st, len, pre1, dir, nrings1, nrings2);
    newnode = patchSplitSingle(newnode, st, len, pre2, dir, nrings1, nrings2);
  }

#ifdef IN_DEBUG_MODE
  dc_printf("Return from PATCHSPLITSINGLE with \n");
  dc_printf("Rings gourp 1:\n");
  printPaths(nrings1);
  dc_printf("Rings group 2:\n");
  printPaths(nrings2);
#endif

  return newnode;
}

Node *Octree::connectFace(
    Node *newnode, int st[3], int len, int dir, PathElement *f1, PathElement *f2)
{
#ifdef IN_DEBUG_MODE
  dc_printf("Call to CONNECTFACE with direction %d and length %d path: \n", dir, len);
  dc_printf("Path(low side): \n");
  printPath(f1);
  //  checkPath(f1);
  dc_printf("Path(high side): \n");
  printPath(f2);
//  checkPath(f2);
#endif

  // Setup 2D
  int pos = st[dir] + len / 2;
  int xdir = (dir + 1) % 3;
  int ydir = (dir + 2) % 3;

  // Use existing intersections on f1 and f2
  int x1, y1, x2, y2;
  float p1, q1, p2, q2;

  getFacePoint(f2->next, dir, x1, y1, p1, q1);
  getFacePoint(f2, dir, x2, y2, p2, q2);

  float dx = x2 + p2 - x1 - p1;
  float dy = y2 + q2 - y1 - q1;

  // Do adapted Bresenham line drawing
  float rx = p1, ry = q1;
  int incx = 1, incy = 1;
  int lx = x1, ly = y1;
  int hx = x2, hy = y2;
  int choice;
  if (x2 < x1) {
    incx = -1;
    rx = 1 - rx;
    lx = x2;
    hx = x1;
  }
  if (y2 < y1) {
    incy = -1;
    ry = 1 - ry;
    ly = y2;
    hy = y1;
  }

  float sx = dx * incx;
  float sy = dy * incy;

  int ori[3];
  ori[dir] = pos / mindimen;
  ori[xdir] = x1;
  ori[ydir] = y1;
  int walkdir;
  int inc;
  float alpha;

  PathElement *curEleN = f1;
  PathElement *curEleP = f2->next;
  Node *nodeN = nullptr, *nodeP = nullptr;
  LeafNode *curN = locateLeaf(&newnode->internal, len, f1->pos);
  LeafNode *curP = locateLeaf(&newnode->internal, len, f2->next->pos);
  if (curN == nullptr || curP == nullptr) {
    exit(0);
  }
  int stN[3], stP[3];
  int lenN, lenP;

  /* Unused code, leaving for posterity

     float stpt[3], edpt[3];
     stpt[dir] = edpt[dir] =(float) pos;
     stpt[xdir] =(x1 + p1) * mindimen;
     stpt[ydir] =(y1 + q1) * mindimen;
     edpt[xdir] =(x2 + p2) * mindimen;
     edpt[ydir] =(y2 + q2) * mindimen;
   */
  while (ori[xdir] != x2 || ori[ydir] != y2) {
    int next;
    if (sy * (1 - rx) > sx * (1 - ry)) {
      choice = 1;
      next = ori[ydir] + incy;
      if (next < ly || next > hy) {
        choice = 4;
        next = ori[xdir] + incx;
      }
    }
    else {
      choice = 2;
      next = ori[xdir] + incx;
      if (next < lx || next > hx) {
        choice = 3;
        next = ori[ydir] + incy;
      }
    }

    if (choice & 1) {
      ori[ydir] = next;
      if (choice == 1) {
        rx += (sy == 0 ? 0 : (1 - ry) * sx / sy);
        ry = 0;
      }

      walkdir = 2;
      inc = incy;
      alpha = x2 < x1 ? 1 - rx : rx;
    }
    else {
      ori[xdir] = next;
      if (choice == 2) {
        ry += (sx == 0 ? 0 : (1 - rx) * sy / sx);
        rx = 0;
      }

      walkdir = 1;
      inc = incx;
      alpha = y2 < y1 ? 1 - ry : ry;
    }

    // Get the exact location of the marcher
    int nori[3] = {ori[0] * mindimen, ori[1] * mindimen, ori[2] * mindimen};
    float spt[3] = {(float)nori[0], (float)nori[1], (float)nori[2]};
    spt[(dir + (3 - walkdir)) % 3] += alpha * mindimen;
    if (inc < 0) {
      spt[(dir + walkdir) % 3] += mindimen;
    }

#if 0
    dc_printf("new x,y: %d %d\n", ori[xdir] / edgelen, ori[ydir] / edgelen);
    dc_printf("nori: %d %d %d alpha: %f walkdir: %d\n", nori[0], nori[1], nori[2], alpha, walkdir);
    dc_printf("%f %f %f\n", spt[0], spt[1], spt[2]);
#endif

    // Locate the current cells on both sides
    newnode = locateCell(&newnode->internal, st, len, nori, dir, 1, nodeN, stN, lenN);
    newnode = locateCell(&newnode->internal, st, len, nori, dir, 0, nodeP, stP, lenP);

    updateParent(&newnode->internal, len, st);

    // Add the cells to the rings and fill in the patch
    PathElement *newEleN;
    if (curEleN->pos[0] != stN[0] || curEleN->pos[1] != stN[1] || curEleN->pos[2] != stN[2]) {
      if (curEleN->next->pos[0] != stN[0] || curEleN->next->pos[1] != stN[1] ||
          curEleN->next->pos[2] != stN[2])
      {
        newEleN = new PathElement;
        newEleN->next = curEleN->next;
        newEleN->pos[0] = stN[0];
        newEleN->pos[1] = stN[1];
        newEleN->pos[2] = stN[2];

        curEleN->next = newEleN;
      }
      else {
        newEleN = curEleN->next;
      }
      curN = patchAdjacent(&newnode->internal,
                           len,
                           curEleN->pos,
                           curN,
                           newEleN->pos,
                           (LeafNode *)nodeN,
                           walkdir,
                           inc,
                           dir,
                           1,
                           alpha);

      curEleN = newEleN;
    }

    PathElement *newEleP;
    if (curEleP->pos[0] != stP[0] || curEleP->pos[1] != stP[1] || curEleP->pos[2] != stP[2]) {
      if (f2->pos[0] != stP[0] || f2->pos[1] != stP[1] || f2->pos[2] != stP[2]) {
        newEleP = new PathElement;
        newEleP->next = curEleP;
        newEleP->pos[0] = stP[0];
        newEleP->pos[1] = stP[1];
        newEleP->pos[2] = stP[2];

        f2->next = newEleP;
      }
      else {
        newEleP = f2;
      }
      curP = patchAdjacent(&newnode->internal,
                           len,
                           curEleP->pos,
                           curP,
                           newEleP->pos,
                           (LeafNode *)nodeP,
                           walkdir,
                           inc,
                           dir,
                           0,
                           alpha);

      curEleP = newEleP;
    }

    /*
       if(flag == 0) {
        dc_printf("error: non-synchronized patching! at \n");
       }
     */
  }

#ifdef IN_DEBUG_MODE
  dc_printf("Return from CONNECTFACE with \n");
  dc_printf("Path(low side):\n");
  printPath(f1);
  checkPath(f1);
  dc_printf("Path(high side):\n");
  printPath(f2);
  checkPath(f2);
#endif

  return newnode;
}

LeafNode *Octree::patchAdjacent(InternalNode *node,
                                int len,
                                int st1[3],
                                LeafNode *leaf1,
                                int st2[3],
                                LeafNode *leaf2,
                                int walkdir,
                                int inc,
                                int dir,
                                int side,
                                float alpha)
{
#ifdef IN_DEBUG_MODE
  dc_printf("Before patching.\n");
  printInfo(st1);
  printInfo(st2);
  dc_printf(
      "-----------------%d %d %d; %d %d %d\n", st1[0], st2[1], st1[2], st2[0], st2[1], st2[2]);
#endif

  // Get edge index on each leaf
  int edgedir = (dir + (3 - walkdir)) % 3;
  int incdir = (dir + walkdir) % 3;
  int ind1 = (edgedir == 1 ? (dir + 3 - edgedir) % 3 - 1 : 2 - (dir + 3 - edgedir) % 3);
  int ind2 = (edgedir == 1 ? (incdir + 3 - edgedir) % 3 - 1 : 2 - (incdir + 3 - edgedir) % 3);

  int eind1 = ((edgedir << 2) | (side << ind1) | ((inc > 0 ? 1 : 0) << ind2));
  int eind2 = ((edgedir << 2) | (side << ind1) | ((inc > 0 ? 0 : 1) << ind2));

#ifdef IN_DEBUG_MODE
  dc_printf("Index 1: %d Alpha 1: %f Index 2: %d Alpha 2: %f\n", eind1, alpha, eind2, alpha);
  /*
     if(alpha < 0 || alpha > 1) {
      dc_printf("Index 1: %d Alpha 1: %f Index 2: %d Alpha 2: %f\n", eind1, alpha, eind2, alpha);
      printInfo(st1);
      printInfo(st2);
     }
   */
#endif

  // Flip edge parity
  LeafNode *nleaf1 = flipEdge(leaf1, eind1, alpha);
  LeafNode *nleaf2 = flipEdge(leaf2, eind2, alpha);

  // Update parent link
  updateParent(node, len, st1, nleaf1);
  updateParent(node, len, st2, nleaf2);
  // updateParent(nleaf1, mindimen, st1);
  // updateParent(nleaf2, mindimen, st2);

  /*
     float m[3];
     dc_printf("Adding new point: %f %f %f\n", spt[0], spt[1], spt[2]);
     getMinimizer(leaf1, m);
     dc_printf("Cell %d now has minimizer %f %f %f\n", leaf1, m[0], m[1], m[2]);
     getMinimizer(leaf2, m);
     dc_printf("Cell %d now has minimizer %f %f %f\n", leaf2, m[0], m[1], m[2]);
   */

#ifdef IN_DEBUG_MODE
  dc_printf("After patching.\n");
  printInfo(st1);
  printInfo(st2);
#endif
  return nleaf2;
}

Node *Octree::locateCell(InternalNode *node,
                         const int st[3],
                         int len,
                         int ori[3],
                         int dir,
                         int side,
                         Node *&rleaf,
                         int rst[3],
                         int &rlen)
{
#ifdef IN_DEBUG_MODE
  // dc_printf("Call to LOCATECELL with node ");
  // printNode(node);
#endif

  int i;
  len >>= 1;
  int ind = 0;
  for (i = 0; i < 3; i++) {
    ind <<= 1;
    if (i == dir && side == 1) {
      ind |= (ori[i] <= (st[i] + len) ? 0 : 1);
    }
    else {
      ind |= (ori[i] < (st[i] + len) ? 0 : 1);
    }
  }

#ifdef IN_DEBUG_MODE
#  if 0
  dc_printf(
      "In LOCATECELL index of ori(%d %d %d) with dir %d side %d in st(%d %d %d, %d) is: %d\n",
      ori[0],
      ori[1],
      ori[2],
      dir,
      side,
      st[0],
      st[1],
      st[2],
      len,
      ind);
#  endif
#endif

  rst[0] = st[0] + vertmap[ind][0] * len;
  rst[1] = st[1] + vertmap[ind][1] * len;
  rst[2] = st[2] + vertmap[ind][2] * len;

  if (node->has_child(ind)) {
    int count = node->get_child_count(ind);
    Node *chd = node->get_child(count);
    if (node->is_child_leaf(ind)) {
      rleaf = chd;
      rlen = len;
    }
    else {
      // Recur
      node->set_child(count,
                      locateCell(&chd->internal, rst, len, ori, dir, side, rleaf, rst, rlen));
    }
  }
  else {
    // Create a new child here
    if (len == mindimen) {
      LeafNode *chd = createLeaf(0);
      node = addChild(node, ind, (Node *)chd, 1);
      rleaf = (Node *)chd;
      rlen = len;
    }
    else {
      // Subdivide the empty cube
      InternalNode *chd = createInternal(0);
      node = addChild(node, ind, locateCell(chd, rst, len, ori, dir, side, rleaf, rst, rlen), 0);
    }
  }

#ifdef IN_DEBUG_MODE
  // dc_printf("Return from LOCATECELL with node ");
  // printNode(newnode);
#endif
  return (Node *)node;
}

void Octree::checkElement(PathElement * /*ele*/)
{
#if 0
  if (ele != nullptr && locateLeafCheck(ele->pos) != ele->node) {
    dc_printf("Screwed! at pos: %d %d %d\n",
              ele->pos[0] >> minshift,
              ele->pos[1] >> minshift,
              ele->pos[2] >> minshift);
    exit(0);
  }
#endif
}

void Octree::checkPath(PathElement *path)
{
  PathElement *n = path;
  int same = 0;
  while (n && (same == 0 || n != path)) {
    same++;
    checkElement(n);
    n = n->next;
  }
}

void Octree::testFacePoint(PathElement *e1, PathElement *e2)
{
  int i;
  PathElement *e = nullptr;
  for (i = 0; i < 3; i++) {
    if (e1->pos[i] != e2->pos[i]) {
      if (e1->pos[i] < e2->pos[i]) {
        e = e2;
      }
      else {
        e = e1;
      }
      break;
    }
  }

  int x, y;
  float p, q;
  dc_printf("Test.");
  getFacePoint(e, i, x, y, p, q);
}

void Octree::getFacePoint(PathElement *leaf, int dir, int &x, int &y, float &p, float &q)
{
  // Find average intersections
  float avg[3] = {0, 0, 0};
  float off[3];
  int num = 0, num2 = 0;

  (void)num2;  // Unused in release builds.

  LeafNode *leafnode = locateLeaf(leaf->pos);
  for (int i = 0; i < 4; i++) {
    int edgeind = faceMap[dir * 2][i];
    int nst[3];
    for (int j = 0; j < 3; j++) {
      nst[j] = leaf->pos[j] + mindimen * vertmap[edgemap[edgeind][0]][j];
    }

    if (getEdgeIntersectionByIndex(nst, edgeind / 4, off, 1)) {
      avg[0] += off[0];
      avg[1] += off[1];
      avg[2] += off[2];
      num++;
    }
    if (getEdgeParity(leafnode, edgeind)) {
      num2++;
    }
  }
  if (num == 0) {
    dc_printf("Wrong! dir: %d pos: %d %d %d num: %d\n",
              dir,
              leaf->pos[0] >> minshift,
              leaf->pos[1] >> minshift,
              leaf->pos[2] >> minshift,
              num2);
    avg[0] = (float)leaf->pos[0];
    avg[1] = (float)leaf->pos[1];
    avg[2] = (float)leaf->pos[2];
  }
  else {

    avg[0] /= num;
    avg[1] /= num;
    avg[2] /= num;

    // avg[0] =(float) leaf->pos[0];
    // avg[1] =(float) leaf->pos[1];
    // avg[2] =(float) leaf->pos[2];
  }

  int xdir = (dir + 1) % 3;
  int ydir = (dir + 2) % 3;

  float xf = avg[xdir];
  float yf = avg[ydir];

#ifdef IN_DEBUG_MODE
  // Is it outside?
  // PathElement* leaf = leaf1->len < leaf2->len ? leaf1 : leaf2;
#  if 0
  float *m = (leaf == leaf1 ? m1 : m2);
  if (xf < leaf->pos[xdir] || yf < leaf->pos[ydir] || xf > leaf->pos[xdir] + leaf->len ||
      yf > leaf->pos[ydir] + leaf->len) {
    dc_printf("Outside cube(%d %d %d), %d : %d %d %f %f\n",
              leaf->pos[0],
              leaf->pos[1],
              leaf->pos[2],
              leaf->len,
              pos,
              dir,
              xf,
              yf);

    // For now, snap to cell
    xf = m[xdir];
    yf = m[ydir];
  }
#  endif

#  if 0
  if (alpha < 0 || alpha > 1 || xf < leaf->pos[xdir] || xf > leaf->pos[xdir] + leaf->len ||
      yf < leaf->pos[ydir] || yf > leaf->pos[ydir] + leaf->len) {
    dc_printf("Alpha: %f Address: %d and %d\n", alpha, leaf1->node, leaf2->node);
    dc_printf("GETFACEPOINT result:(%d %d %d) %d min:(%f %f %f);(%d %d %d) %d min:(%f %f %f).\n",
              leaf1->pos[0],
              leaf1->pos[1],
              leaf1->pos[2],
              leaf1->len,
              m1[0],
              m1[1],
              m1[2],
              leaf2->pos[0],
              leaf2->pos[1],
              leaf2->pos[2],
              leaf2->len,
              m2[0],
              m2[1],
              m2[2]);
    dc_printf("Face point at dir %d pos %d: %f %f\n", dir, pos, xf, yf);
  }
#  endif
#endif

  // Get the integer and float part
  x = ((leaf->pos[xdir]) >> minshift);
  y = ((leaf->pos[ydir]) >> minshift);

  p = (xf - leaf->pos[xdir]) / mindimen;
  q = (yf - leaf->pos[ydir]) / mindimen;

#ifdef IN_DEBUG_MODE
  dc_printf("Face point at dir %d : %f %f\n", dir, xf, yf);
#endif
}

int Octree::findPair(PathElement *head, int pos, int dir, PathElement *&pre1, PathElement *&pre2)
{
  int side = getSide(head, pos, dir);
  PathElement *cur = head;
  PathElement *anchor;
  PathElement *ppre1, *ppre2;

  // Start from this face, find a pair
  anchor = cur;
  ppre1 = cur;
  cur = cur->next;
  while (cur != anchor && (getSide(cur, pos, dir) == side)) {
    ppre1 = cur;
    cur = cur->next;
  }
  if (cur == anchor) {
    // No pair found
    return side;
  }

  side = getSide(cur, pos, dir);
  ppre2 = cur;
  cur = cur->next;
  while (getSide(cur, pos, dir) == side) {
    ppre2 = cur;
    cur = cur->next;
  }

  // Switch pre1 and pre2 if we start from the higher side
  if (side == -1) {
    cur = ppre1;
    ppre1 = ppre2;
    ppre2 = cur;
  }

  pre1 = ppre1;
  pre2 = ppre2;

  return 0;
}

int Octree::getSide(PathElement *e, int pos, int dir)
{
  return (e->pos[dir] < pos ? -1 : 1);
}

int Octree::isEqual(PathElement *e1, PathElement *e2)
{
  return (e1->pos[0] == e2->pos[0] && e1->pos[1] == e2->pos[1] && e1->pos[2] == e2->pos[2]);
}

void Octree::compressRing(PathElement *&ring)
{
  if (ring == nullptr) {
    return;
  }
#ifdef IN_DEBUG_MODE
  dc_printf("Call to COMPRESSRING with path: \n");
  printPath(ring);
#endif

  PathElement *cur = ring->next->next;
  PathElement *pre = ring->next;
  PathElement *prepre = ring;
  PathElement *anchor = prepre;

  do {
    while (isEqual(cur, prepre)) {
      // Delete
      if (cur == prepre) {
        // The ring has shrinked to a point
        delete pre;
        delete cur;
        anchor = nullptr;
        break;
      }
      prepre->next = cur->next;
      delete pre;
      delete cur;
      pre = prepre->next;
      cur = pre->next;
      anchor = prepre;
    }

    if (anchor == nullptr) {
      break;
    }

    prepre = pre;
    pre = cur;
    cur = cur->next;
  } while (prepre != anchor);

  ring = anchor;

#ifdef IN_DEBUG_MODE
  dc_printf("Return from COMPRESSRING with path: \n");
  printPath(ring);
#endif
}

void Octree::buildSigns()
{
  // First build a lookup table
  // dc_printf("Building up look up table...\n");
  int size = 1 << 12;
  unsigned char table[1 << 12];
  for (int i = 0; i < size; i++) {
    table[i] = 0;
  }
  for (int i = 0; i < 256; i++) {
    int ind = 0;
    for (int j = 11; j >= 0; j--) {
      ind <<= 1;
      if (((i >> edgemap[j][0]) & 1) ^ ((i >> edgemap[j][1]) & 1)) {
        ind |= 1;
      }
    }

    table[ind] = i;
  }

  // Next, traverse the grid
  int sg = 1;
  int cube[8];
  buildSigns(table, root, 0, sg, cube);
}

void Octree::buildSigns(unsigned char table[], Node *node, int isLeaf, int sg, int rvalue[8])
{
  if (node == nullptr) {
    for (int i = 0; i < 8; i++) {
      rvalue[i] = sg;
    }
    return;
  }

  if (isLeaf == 0) {
    // Internal node
    Node *chd[8];
    int leaf[8];
    node->internal.fill_children(chd, leaf);

    // Get the signs at the corners of the first cube
    rvalue[0] = sg;
    int oris[8];
    buildSigns(table, chd[0], leaf[0], sg, oris);

    // Get the rest
    int cube[8];
    for (int i = 1; i < 8; i++) {
      buildSigns(table, chd[i], leaf[i], oris[i], cube);
      rvalue[i] = cube[i];
    }
  }
  else {
    // Leaf node
    generateSigns(&node->leaf, table, sg);

    for (int i = 0; i < 8; i++) {
      rvalue[i] = getSign(&node->leaf, i);
    }
  }
}

void Octree::floodFill()
{
  // int threshold =(int)((dimen/mindimen) *(dimen/mindimen) * 0.5f);
  int st[3] = {0, 0, 0};

  // First, check for largest component
  // size stored in -threshold
  clearProcessBits(root, maxDepth);
  int threshold = floodFill(root, st, dimen, maxDepth, 0);

  // Next remove
  dc_printf("Largest component: %d\n", threshold);
  threshold *= thresh;
  dc_printf("Removing all components smaller than %d\n", threshold);

  int st2[3] = {0, 0, 0};
  clearProcessBits(root, maxDepth);
  floodFill(root, st2, dimen, maxDepth, threshold);
}

void Octree::clearProcessBits(Node *node, int height)
{
  int i;

  if (height == 0) {
    // Leaf cell,
    for (i = 0; i < 12; i++) {
      setOutProcess(&node->leaf, i);
    }
  }
  else {
    // Internal cell, recur
    int count = 0;
    for (i = 0; i < 8; i++) {
      if (node->internal.has_child(i)) {
        clearProcessBits(node->internal.get_child(count), height - 1);
        count++;
      }
    }
  }
}

int Octree::floodFill(LeafNode *leaf, const int st[3], int len, int /*height*/, int threshold)
{
  int i, j;
  int maxtotal = 0;

  // Leaf cell,
  int par, inp;

  // Test if the leaf has intersection edges
  for (i = 0; i < 12; i++) {
    par = getEdgeParity(leaf, i);
    inp = isInProcess(leaf, i);

    if (par == 1 && inp == 0) {
      // Intersection edge, hasn't been processed
      // Let's start filling
      GridQueue *queue = new GridQueue();
      int total = 1;

      // Set to in process
      int mst[3];
      mst[0] = st[0] + vertmap[edgemap[i][0]][0] * len;
      mst[1] = st[1] + vertmap[edgemap[i][0]][1] * len;
      mst[2] = st[2] + vertmap[edgemap[i][0]][2] * len;
      int mdir = i / 4;
      setInProcessAll(mst, mdir);

      // Put this edge into queue
      queue->pushQueue(mst, mdir);

      // Queue processing
      int nst[3], dir;
      while (queue->popQueue(nst, dir) == 1) {
#if 0
        dc_printf("nst: %d %d %d, dir: %d\n",
                  nst[0] / mindimen,
                  nst[1] / mindimen,
                  nst[2] / mindimen,
                  dir);
#endif
        // locations
        int stMask[3][3] = {{0, 0 - len, 0 - len}, {0 - len, 0, 0 - len}, {0 - len, 0 - len, 0}};
        int cst[2][3];
        for (j = 0; j < 3; j++) {
          cst[0][j] = nst[j];
          cst[1][j] = nst[j] + stMask[dir][j];
        }

        // cells
        LeafNode *cs[2];
        for (j = 0; j < 2; j++) {
          cs[j] = locateLeaf(cst[j]);
        }

        // Middle sign
        int s = getSign(cs[0], 0);

        // Masks
        int fcCells[4] = {1, 0, 1, 0};
        int fcEdges[3][4][3] = {{{9, 2, 11}, {8, 1, 10}, {5, 1, 7}, {4, 2, 6}},
                                {{10, 6, 11}, {8, 5, 9}, {1, 5, 3}, {0, 6, 2}},
                                {{6, 10, 7}, {4, 9, 5}, {2, 9, 3}, {0, 10, 1}}};

        // Search for neighboring connected intersection edges
        for (int find = 0; find < 4; find++) {
          int cind = fcCells[find];
          int eind, edge;
          if (s == 0) {
            // Original order
            for (eind = 0; eind < 3; eind++) {
              edge = fcEdges[dir][find][eind];
              if (getEdgeParity(cs[cind], edge) == 1) {
                break;
              }
            }
          }
          else {
            // Inverse order
            for (eind = 2; eind >= 0; eind--) {
              edge = fcEdges[dir][find][eind];
              if (getEdgeParity(cs[cind], edge) == 1) {
                break;
              }
            }
          }

          if (eind == 3 || eind == -1) {
            dc_printf("Wrong! this is not a consistent sign. %d\n", eind);
          }
          else {
            int est[3];
            est[0] = cst[cind][0] + vertmap[edgemap[edge][0]][0] * len;
            est[1] = cst[cind][1] + vertmap[edgemap[edge][0]][1] * len;
            est[2] = cst[cind][2] + vertmap[edgemap[edge][0]][2] * len;
            int edir = edge / 4;

            if (isInProcess(cs[cind], edge) == 0) {
              setInProcessAll(est, edir);
              queue->pushQueue(est, edir);
#if 0
              dc_printf("Pushed: est: %d %d %d, edir: %d\n",
                        est[0] / len,
                        est[1] / len,
                        est[2] / len,
                        edir);
#endif
              total++;
            }
          }
        }
      }

      dc_printf("Size of component: %d ", total);

      if (threshold == 0) {
        // Measuring stage
        maxtotal = std::max(total, maxtotal);
        dc_printf(".\n");
        delete queue;
        continue;
      }

      if (total >= threshold) {
        dc_printf("Maintained.\n");
        delete queue;
        continue;
      }
      dc_printf("Less than %d, removing...\n", threshold);

      // We have to remove this noise

      // Flip parity
      // setOutProcessAll(mst, mdir);
      flipParityAll(mst, mdir);

      // Put this edge into queue
      queue->pushQueue(mst, mdir);

      // Queue processing
      while (queue->popQueue(nst, dir) == 1) {
#if 0
        dc_printf("nst: %d %d %d, dir: %d\n",
                  nst[0] / mindimen,
                  nst[1] / mindimen,
                  nst[2] / mindimen,
                  dir);
#endif
        // locations
        int stMask[3][3] = {{0, 0 - len, 0 - len}, {0 - len, 0, 0 - len}, {0 - len, 0 - len, 0}};
        int cst[2][3];
        for (j = 0; j < 3; j++) {
          cst[0][j] = nst[j];
          cst[1][j] = nst[j] + stMask[dir][j];
        }

        // cells
        LeafNode *cs[2];
        for (j = 0; j < 2; j++) {
          cs[j] = locateLeaf(cst[j]);
        }

        // Middle sign
        int s = getSign(cs[0], 0);

        // Masks
        int fcCells[4] = {1, 0, 1, 0};
        int fcEdges[3][4][3] = {{{9, 2, 11}, {8, 1, 10}, {5, 1, 7}, {4, 2, 6}},
                                {{10, 6, 11}, {8, 5, 9}, {1, 5, 3}, {0, 6, 2}},
                                {{6, 10, 7}, {4, 9, 5}, {2, 9, 3}, {0, 10, 1}}};

        // Search for neighboring connected intersection edges
        for (int find = 0; find < 4; find++) {
          int cind = fcCells[find];
          int eind, edge;
          if (s == 0) {
            // Original order
            for (eind = 0; eind < 3; eind++) {
              edge = fcEdges[dir][find][eind];
              if (isInProcess(cs[cind], edge) == 1) {
                break;
              }
            }
          }
          else {
            // Inverse order
            for (eind = 2; eind >= 0; eind--) {
              edge = fcEdges[dir][find][eind];
              if (isInProcess(cs[cind], edge) == 1) {
                break;
              }
            }
          }

          if (eind == 3 || eind == -1) {
            dc_printf("Wrong! this is not a consistent sign. %d\n", eind);
          }
          else {
            int est[3];
            est[0] = cst[cind][0] + vertmap[edgemap[edge][0]][0] * len;
            est[1] = cst[cind][1] + vertmap[edgemap[edge][0]][1] * len;
            est[2] = cst[cind][2] + vertmap[edgemap[edge][0]][2] * len;
            int edir = edge / 4;

            if (getEdgeParity(cs[cind], edge) == 1) {
              flipParityAll(est, edir);
              queue->pushQueue(est, edir);
#if 0
              dc_printf("Pushed: est: %d %d %d, edir: %d\n",
                        est[0] / len,
                        est[1] / len,
                        est[2] / len,
                        edir);
#endif
              total++;
            }
          }
        }
      }

      delete queue;
    }
  }

  return maxtotal;
}

int Octree::floodFill(Node *node, int st[3], int len, int height, int threshold)
{
  int i;
  int maxtotal = 0;

  if (height == 0) {
    maxtotal = floodFill(&node->leaf, st, len, height, threshold);
  }
  else {
    // Internal cell, recur
    int count = 0;
    len >>= 1;
    for (i = 0; i < 8; i++) {
      if (node->internal.has_child(i)) {
        int nst[3];
        nst[0] = st[0] + vertmap[i][0] * len;
        nst[1] = st[1] + vertmap[i][1] * len;
        nst[2] = st[2] + vertmap[i][2] * len;

        int d = floodFill(node->internal.get_child(count), nst, len, height - 1, threshold);
        maxtotal = std::max(d, maxtotal);
        count++;
      }
    }
  }

  return maxtotal;
}

void Octree::writeOut()
{
  int numQuads = 0;
  int numVertices = 0;
  int numEdges = 0;

  countIntersection(root, maxDepth, numQuads, numVertices, numEdges);

  dc_printf("Vertices counted: %d Polys counted: %d \n", numVertices, numQuads);
  output_mesh = alloc_output(numVertices, numQuads);
  int offset = 0;
  int st[3] = {0, 0, 0};

  // First, output vertices
  offset = 0;
  actualVerts = 0;
  actualQuads = 0;

  generateMinimizer(root, st, dimen, maxDepth, offset);
  cellProcContour(root, 0, maxDepth);
  dc_printf("Vertices written: %d Quads written: %d \n", offset, actualQuads);
}

void Octree::countIntersection(Node *node, int height, int &nedge, int &ncell, int &nface)
{
  if (height > 0) {
    int total = node->internal.get_num_children();
    for (int i = 0; i < total; i++) {
      countIntersection(node->internal.get_child(i), height - 1, nedge, ncell, nface);
    }
  }
  else {
    nedge += getNumEdges2(&node->leaf);

    int smask = getSignMask(&node->leaf);

    if (use_manifold) {
      int comps = manifold_table[smask].comps;
      ncell += comps;
    }
    else {
      if (smask > 0 && smask < 255) {
        ncell++;
      }
    }

    for (int i = 0; i < 3; i++) {
      if (getFaceEdgeNum(&node->leaf, i * 2)) {
        nface++;
      }
    }
  }
}

/* from http://eigen.tuxfamily.org/bz/show_bug.cgi?id=257 */
static void pseudoInverse(const Eigen::Matrix3f &a, Eigen::Matrix3f &result, float tolerance)
{
  const int Options = Eigen::ComputeFullU | Eigen::ComputeFullV;
  Eigen::JacobiSVD<Eigen::Matrix3f, Options> svd = a.jacobiSvd<Options>();

  result = svd.matrixV() *
           Eigen::Vector3f((svd.singularValues().array().abs() > tolerance)
                               .select(svd.singularValues().array().inverse(), 0))
               .asDiagonal() *
           svd.matrixU().adjoint();
}

static void solve_least_squares(const float halfA[],
                                const float b[],
                                const float midpoint[],
                                float rvalue[])
{
  /* calculate pseudo-inverse */
  Eigen::Matrix3f A, pinv;
  A << halfA[0], halfA[1], halfA[2], halfA[1], halfA[3], halfA[4], halfA[2], halfA[4], halfA[5];
  pseudoInverse(A, pinv, 0.1f);

  Eigen::Vector3f b2(b), mp(midpoint), result;
  b2 = b2 + A * -mp;
  result = pinv * b2 + mp;

  for (int i = 0; i < 3; i++) {
    rvalue[i] = result(i);
  }
}

static void mass_point(float mp[3], const float pts[12][3], const int parity[12])
{
  int ec = 0;

  for (int i = 0; i < 12; i++) {
    if (parity[i]) {
      const float *p = pts[i];

      mp[0] += p[0];
      mp[1] += p[1];
      mp[2] += p[2];

      ec++;
    }
  }

  if (ec == 0) {
    return;
  }
  mp[0] /= ec;
  mp[1] /= ec;
  mp[2] /= ec;
}

static void minimize(float rvalue[3],
                     float mp[3],
                     const float pts[12][3],
                     const float norms[12][3],
                     const int parity[12])
{
  float ata[6] = {0, 0, 0, 0, 0, 0};
  float atb[3] = {0, 0, 0};
  int ec = 0;

  for (int i = 0; i < 12; i++) {
    // if(getEdgeParity(leaf, i))
    if (parity[i]) {
      const float *norm = norms[i];
      const float *p = pts[i];

      // QEF
      ata[0] += (float)(norm[0] * norm[0]);
      ata[1] += (float)(norm[0] * norm[1]);
      ata[2] += (float)(norm[0] * norm[2]);
      ata[3] += (float)(norm[1] * norm[1]);
      ata[4] += (float)(norm[1] * norm[2]);
      ata[5] += (float)(norm[2] * norm[2]);

      const float pn = p[0] * norm[0] + p[1] * norm[1] + p[2] * norm[2];

      atb[0] += (float)(norm[0] * pn);
      atb[1] += (float)(norm[1] * pn);
      atb[2] += (float)(norm[2] * pn);

      // Minimizer
      mp[0] += p[0];
      mp[1] += p[1];
      mp[2] += p[2];

      ec++;
    }
  }

  if (ec == 0) {
    return;
  }
  mp[0] /= ec;
  mp[1] /= ec;
  mp[2] /= ec;

  // Solve least squares
  solve_least_squares(ata, atb, mp, rvalue);
}

void Octree::computeMinimizer(const LeafNode *leaf, int st[3], int len, float rvalue[3]) const
{
  // First, gather all edge intersections
  float pts[12][3], norms[12][3];
  int parity[12];
  fillEdgeIntersections(leaf, st, len, pts, norms, parity);

  switch (mode) {
    case DUALCON_CENTROID:
      rvalue[0] = (float)st[0] + len / 2;
      rvalue[1] = (float)st[1] + len / 2;
      rvalue[2] = (float)st[2] + len / 2;
      break;

    case DUALCON_MASS_POINT:
      rvalue[0] = rvalue[1] = rvalue[2] = 0;
      mass_point(rvalue, pts, parity);
      break;

    default: {
      // Sharp features */

      // construct QEF and minimizer
      float mp[3] = {0, 0, 0};
      minimize(rvalue, mp, pts, norms, parity);

      /* Restraining the location of the minimizer */
      float nh1 = hermite_num * len;
      float nh2 = (1 + hermite_num) * len;

      if (rvalue[0] < st[0] - nh1 || rvalue[1] < st[1] - nh1 || rvalue[2] < st[2] - nh1 ||

          rvalue[0] > st[0] + nh2 || rvalue[1] > st[1] + nh2 || rvalue[2] > st[2] + nh2)
      {
        // Use mass point instead
        rvalue[0] = mp[0];
        rvalue[1] = mp[1];
        rvalue[2] = mp[2];
      }
      break;
    }
  }
}

void Octree::generateMinimizer(Node *node, int st[3], int len, int height, int &offset)
{
  int i, j;

  if (height == 0) {
    // Leaf cell, generate

    // First, find minimizer
    float rvalue[3];
    rvalue[0] = (float)st[0] + len / 2;
    rvalue[1] = (float)st[1] + len / 2;
    rvalue[2] = (float)st[2] + len / 2;
    computeMinimizer(&node->leaf, st, len, rvalue);

    // Update
    // float fnst[3];
    for (j = 0; j < 3; j++) {
      rvalue[j] = rvalue[j] * range / dimen + origin[j];
      // fnst[j] = st[j] * range / dimen + origin[j];
    }

    int mult = 0, smask = getSignMask(&node->leaf);

    if (use_manifold) {
      mult = manifold_table[smask].comps;
    }
    else {
      if (smask > 0 && smask < 255) {
        mult = 1;
      }
    }

    for (j = 0; j < mult; j++) {
      add_vert(output_mesh, rvalue);
    }

    // Store the index
    setMinimizerIndex(&node->leaf, offset);

    offset += mult;
  }
  else {
    // Internal cell, recur
    int count = 0;
    len >>= 1;
    for (i = 0; i < 8; i++) {
      if (node->internal.has_child(i)) {
        int nst[3];
        nst[0] = st[0] + vertmap[i][0] * len;
        nst[1] = st[1] + vertmap[i][1] * len;
        nst[2] = st[2] + vertmap[i][2] * len;

        generateMinimizer(node->internal.get_child(count), nst, len, height - 1, offset);
        count++;
      }
    }
  }
}

void Octree::processEdgeWrite(Node *node[4], int /*depth*/[4], int /*maxdep*/, int dir)
{
  // int color = 0;

  int i = 3;
  {
    if (getEdgeParity((LeafNode *)(node[i]), processEdgeMask[dir][i])) {
      int flip = 0;
      int edgeind = processEdgeMask[dir][i];
      if (getSign((LeafNode *)node[i], edgemap[edgeind][1]) > 0) {
        flip = 1;
      }

      int num = 0;
      {
        int ind[8];
        if (use_manifold) {
          int vind[2];
          int seq[4] = {0, 1, 3, 2};
          for (int k = 0; k < 4; k++) {
            getMinimizerIndices((LeafNode *)(node[seq[k]]), processEdgeMask[dir][seq[k]], vind);
            ind[num] = vind[0];
            num++;

            if (vind[1] != -1) {
              ind[num] = vind[1];
              num++;
              if (flip == 0) {
                ind[num - 1] = vind[0];
                ind[num - 2] = vind[1];
              }
            }
          }

          /* we don't use the manifold option, but if it is
             ever enabled again note that it can output
             non-quads */
        }
        else {
          if (flip) {
            ind[0] = getMinimizerIndex((LeafNode *)(node[2]));
            ind[1] = getMinimizerIndex((LeafNode *)(node[3]));
            ind[2] = getMinimizerIndex((LeafNode *)(node[1]));
            ind[3] = getMinimizerIndex((LeafNode *)(node[0]));
          }
          else {
            ind[0] = getMinimizerIndex((LeafNode *)(node[0]));
            ind[1] = getMinimizerIndex((LeafNode *)(node[1]));
            ind[2] = getMinimizerIndex((LeafNode *)(node[3]));
            ind[3] = getMinimizerIndex((LeafNode *)(node[2]));
          }

          add_quad(output_mesh, ind);
        }
      }
      return;
    }
    return;
  }
}

void Octree::edgeProcContour(Node *node[4], const int leaf[4], int depth[4], int maxdep, int dir)
{
  if (!(node[0] && node[1] && node[2] && node[3])) {
    return;
  }
  if (leaf[0] && leaf[1] && leaf[2] && leaf[3]) {
    processEdgeWrite(node, depth, maxdep, dir);
  }
  else {
    int i, j;
    Node *chd[4][8];
    for (j = 0; j < 4; j++) {
      for (i = 0; i < 8; i++) {
        chd[j][i] = ((!leaf[j]) && node[j]->internal.has_child(i)) ?
                        node[j]->internal.get_child(node[j]->internal.get_child_count(i)) :
                        nullptr;
      }
    }

    // 2 edge calls
    Node *ne[4];
    int le[4];
    int de[4];
    for (i = 0; i < 2; i++) {
      int c[4] = {edgeProcEdgeMask[dir][i][0],
                  edgeProcEdgeMask[dir][i][1],
                  edgeProcEdgeMask[dir][i][2],
                  edgeProcEdgeMask[dir][i][3]};

      for (int j = 0; j < 4; j++) {
        if (leaf[j]) {
          le[j] = leaf[j];
          ne[j] = node[j];
          de[j] = depth[j];
        }
        else {
          le[j] = node[j]->internal.is_child_leaf(c[j]);
          ne[j] = chd[j][c[j]];
          de[j] = depth[j] - 1;
        }
      }

      edgeProcContour(ne, le, de, maxdep - 1, edgeProcEdgeMask[dir][i][4]);
    }
  }
}

void Octree::faceProcContour(
    Node *node[2], const int leaf[2], const int depth[2], int maxdep, int dir)
{
  if (!(node[0] && node[1])) {
    return;
  }

  if (!(leaf[0] && leaf[1])) {
    int i, j;
    // Fill children nodes
    Node *chd[2][8];
    for (j = 0; j < 2; j++) {
      for (i = 0; i < 8; i++) {
        chd[j][i] = ((!leaf[j]) && node[j]->internal.has_child(i)) ?
                        node[j]->internal.get_child(node[j]->internal.get_child_count(i)) :
                        nullptr;
      }
    }

    // 4 face calls
    Node *nf[2];
    int df[2];
    int lf[2];
    for (i = 0; i < 4; i++) {
      int c[2] = {faceProcFaceMask[dir][i][0], faceProcFaceMask[dir][i][1]};
      for (int j = 0; j < 2; j++) {
        if (leaf[j]) {
          lf[j] = leaf[j];
          nf[j] = node[j];
          df[j] = depth[j];
        }
        else {
          lf[j] = node[j]->internal.is_child_leaf(c[j]);
          nf[j] = chd[j][c[j]];
          df[j] = depth[j] - 1;
        }
      }
      faceProcContour(nf, lf, df, maxdep - 1, faceProcFaceMask[dir][i][2]);
    }

    // 4 edge calls
    int orders[2][4] = {{0, 0, 1, 1}, {0, 1, 0, 1}};
    Node *ne[4];
    int le[4];
    int de[4];

    for (i = 0; i < 4; i++) {
      int c[4] = {faceProcEdgeMask[dir][i][1],
                  faceProcEdgeMask[dir][i][2],
                  faceProcEdgeMask[dir][i][3],
                  faceProcEdgeMask[dir][i][4]};
      int *order = orders[faceProcEdgeMask[dir][i][0]];

      for (int j = 0; j < 4; j++) {
        if (leaf[order[j]]) {
          le[j] = leaf[order[j]];
          ne[j] = node[order[j]];
          de[j] = depth[order[j]];
        }
        else {
          le[j] = node[order[j]]->internal.is_child_leaf(c[j]);
          ne[j] = chd[order[j]][c[j]];
          de[j] = depth[order[j]] - 1;
        }
      }

      edgeProcContour(ne, le, de, maxdep - 1, faceProcEdgeMask[dir][i][5]);
    }
  }
}

void Octree::cellProcContour(Node *node, int leaf, int depth)
{
  if (node == nullptr) {
    return;
  }

  if (!leaf) {
    int i;

    // Fill children nodes
    Node *chd[8];
    for (i = 0; i < 8; i++) {
      chd[i] = ((!leaf) && node->internal.has_child(i)) ?
                   node->internal.get_child(node->internal.get_child_count(i)) :
                   nullptr;
    }

    // 8 Cell calls
    for (i = 0; i < 8; i++) {
      cellProcContour(chd[i], node->internal.is_child_leaf(i), depth - 1);
    }

    // 12 face calls
    Node *nf[2];
    int lf[2];
    int df[2] = {depth - 1, depth - 1};
    for (i = 0; i < 12; i++) {
      int c[2] = {cellProcFaceMask[i][0], cellProcFaceMask[i][1]};

      lf[0] = node->internal.is_child_leaf(c[0]);
      lf[1] = node->internal.is_child_leaf(c[1]);

      nf[0] = chd[c[0]];
      nf[1] = chd[c[1]];

      faceProcContour(nf, lf, df, depth - 1, cellProcFaceMask[i][2]);
    }

    // 6 edge calls
    Node *ne[4];
    int le[4];
    int de[4] = {depth - 1, depth - 1, depth - 1, depth - 1};
    for (i = 0; i < 6; i++) {
      int c[4] = {cellProcEdgeMask[i][0],
                  cellProcEdgeMask[i][1],
                  cellProcEdgeMask[i][2],
                  cellProcEdgeMask[i][3]};

      for (int j = 0; j < 4; j++) {
        le[j] = node->internal.is_child_leaf(c[j]);
        ne[j] = chd[c[j]];
      }

      edgeProcContour(ne, le, de, depth - 1, cellProcEdgeMask[i][4]);
    }
  }
}

void Octree::processEdgeParity(LeafNode *node[4], const int /*depth*/[4], int /*maxdep*/, int dir)
{
  int con = 0;
  for (int i = 0; i < 4; i++) {
    // Minimal cell
    // if(op == 0)
    {
      if (getEdgeParity(node[i], processEdgeMask[dir][i])) {
        con = 1;
        break;
      }
    }
  }

  if (con == 1) {
    for (int i = 0; i < 4; i++) {
      setEdge(node[i], processEdgeMask[dir][i]);
    }
  }
}

void Octree::edgeProcParity(
    Node *node[4], const int leaf[4], const int depth[4], int maxdep, int dir)
{
  if (!(node[0] && node[1] && node[2] && node[3])) {
    return;
  }
  if (leaf[0] && leaf[1] && leaf[2] && leaf[3]) {
    processEdgeParity((LeafNode **)node, depth, maxdep, dir);
  }
  else {
    int i, j;
    Node *chd[4][8];
    for (j = 0; j < 4; j++) {
      for (i = 0; i < 8; i++) {
        chd[j][i] = ((!leaf[j]) && node[j]->internal.has_child(i)) ?
                        node[j]->internal.get_child(node[j]->internal.get_child_count(i)) :
                        nullptr;
      }
    }

    // 2 edge calls
    Node *ne[4];
    int le[4];
    int de[4];
    for (i = 0; i < 2; i++) {
      int c[4] = {edgeProcEdgeMask[dir][i][0],
                  edgeProcEdgeMask[dir][i][1],
                  edgeProcEdgeMask[dir][i][2],
                  edgeProcEdgeMask[dir][i][3]};

      // int allleaf = 1;
      for (int j = 0; j < 4; j++) {

        if (leaf[j]) {
          le[j] = leaf[j];
          ne[j] = node[j];
          de[j] = depth[j];
        }
        else {
          le[j] = node[j]->internal.is_child_leaf(c[j]);
          ne[j] = chd[j][c[j]];
          de[j] = depth[j] - 1;
        }
      }

      edgeProcParity(ne, le, de, maxdep - 1, edgeProcEdgeMask[dir][i][4]);
    }
  }
}

void Octree::faceProcParity(
    Node *node[2], const int leaf[2], const int depth[2], int maxdep, int dir)
{
  if (!(node[0] && node[1])) {
    return;
  }

  if (!(leaf[0] && leaf[1])) {
    int i, j;
    // Fill children nodes
    Node *chd[2][8];
    for (j = 0; j < 2; j++) {
      for (i = 0; i < 8; i++) {
        chd[j][i] = ((!leaf[j]) && node[j]->internal.has_child(i)) ?
                        node[j]->internal.get_child(node[j]->internal.get_child_count(i)) :
                        nullptr;
      }
    }

    // 4 face calls
    Node *nf[2];
    int df[2];
    int lf[2];
    for (i = 0; i < 4; i++) {
      int c[2] = {faceProcFaceMask[dir][i][0], faceProcFaceMask[dir][i][1]};
      for (int j = 0; j < 2; j++) {
        if (leaf[j]) {
          lf[j] = leaf[j];
          nf[j] = node[j];
          df[j] = depth[j];
        }
        else {
          lf[j] = node[j]->internal.is_child_leaf(c[j]);
          nf[j] = chd[j][c[j]];
          df[j] = depth[j] - 1;
        }
      }
      faceProcParity(nf, lf, df, maxdep - 1, faceProcFaceMask[dir][i][2]);
    }

    // 4 edge calls
    int orders[2][4] = {{0, 0, 1, 1}, {0, 1, 0, 1}};
    Node *ne[4];
    int le[4];
    int de[4];

    for (i = 0; i < 4; i++) {
      int c[4] = {faceProcEdgeMask[dir][i][1],
                  faceProcEdgeMask[dir][i][2],
                  faceProcEdgeMask[dir][i][3],
                  faceProcEdgeMask[dir][i][4]};
      int *order = orders[faceProcEdgeMask[dir][i][0]];

      for (int j = 0; j < 4; j++) {
        if (leaf[order[j]]) {
          le[j] = leaf[order[j]];
          ne[j] = node[order[j]];
          de[j] = depth[order[j]];
        }
        else {
          le[j] = node[order[j]]->internal.is_child_leaf(c[j]);
          ne[j] = chd[order[j]][c[j]];
          de[j] = depth[order[j]] - 1;
        }
      }

      edgeProcParity(ne, le, de, maxdep - 1, faceProcEdgeMask[dir][i][5]);
    }
  }
}

void Octree::cellProcParity(Node *node, int leaf, int depth)
{
  if (node == nullptr) {
    return;
  }

  if (!leaf) {
    int i;

    // Fill children nodes
    Node *chd[8];
    for (i = 0; i < 8; i++) {
      chd[i] = ((!leaf) && node->internal.has_child(i)) ?
                   node->internal.get_child(node->internal.get_child_count(i)) :
                   nullptr;
    }

    // 8 Cell calls
    for (i = 0; i < 8; i++) {
      cellProcParity(chd[i], node->internal.is_child_leaf(i), depth - 1);
    }

    // 12 face calls
    Node *nf[2];
    int lf[2];
    int df[2] = {depth - 1, depth - 1};
    for (i = 0; i < 12; i++) {
      int c[2] = {cellProcFaceMask[i][0], cellProcFaceMask[i][1]};

      lf[0] = node->internal.is_child_leaf(c[0]);
      lf[1] = node->internal.is_child_leaf(c[1]);

      nf[0] = chd[c[0]];
      nf[1] = chd[c[1]];

      faceProcParity(nf, lf, df, depth - 1, cellProcFaceMask[i][2]);
    }

    // 6 edge calls
    Node *ne[4];
    int le[4];
    int de[4] = {depth - 1, depth - 1, depth - 1, depth - 1};
    for (i = 0; i < 6; i++) {
      int c[4] = {cellProcEdgeMask[i][0],
                  cellProcEdgeMask[i][1],
                  cellProcEdgeMask[i][2],
                  cellProcEdgeMask[i][3]};

      for (int j = 0; j < 4; j++) {
        le[j] = node->internal.is_child_leaf(c[j]);
        ne[j] = chd[c[j]];
      }

      edgeProcParity(ne, le, de, depth - 1, cellProcEdgeMask[i][4]);
    }
  }
}

/* definitions for global arrays */
const int edgemask[3] = {5, 3, 6};

const int faceMap[6][4] = {
    {4, 8, 5, 9},
    {6, 10, 7, 11},
    {0, 8, 1, 10},
    {2, 9, 3, 11},
    {0, 4, 2, 6},
    {1, 5, 3, 7},
};

const int cellProcFaceMask[12][3] = {
    {0, 4, 0},
    {1, 5, 0},
    {2, 6, 0},
    {3, 7, 0},
    {0, 2, 1},
    {4, 6, 1},
    {1, 3, 1},
    {5, 7, 1},
    {0, 1, 2},
    {2, 3, 2},
    {4, 5, 2},
    {6, 7, 2},
};

const int cellProcEdgeMask[6][5] = {
    {0, 1, 2, 3, 0},
    {4, 5, 6, 7, 0},
    {0, 4, 1, 5, 1},
    {2, 6, 3, 7, 1},
    {0, 2, 4, 6, 2},
    {1, 3, 5, 7, 2},
};

const int faceProcFaceMask[3][4][3] = {{{4, 0, 0}, {5, 1, 0}, {6, 2, 0}, {7, 3, 0}},
                                       {{2, 0, 1}, {6, 4, 1}, {3, 1, 1}, {7, 5, 1}},
                                       {{1, 0, 2}, {3, 2, 2}, {5, 4, 2}, {7, 6, 2}}};

const int faceProcEdgeMask[3][4][6] = {
    {{1, 4, 0, 5, 1, 1}, {1, 6, 2, 7, 3, 1}, {0, 4, 6, 0, 2, 2}, {0, 5, 7, 1, 3, 2}},
    {{0, 2, 3, 0, 1, 0}, {0, 6, 7, 4, 5, 0}, {1, 2, 0, 6, 4, 2}, {1, 3, 1, 7, 5, 2}},
    {{1, 1, 0, 3, 2, 0}, {1, 5, 4, 7, 6, 0}, {0, 1, 5, 0, 4, 1}, {0, 3, 7, 2, 6, 1}}};

const int edgeProcEdgeMask[3][2][5] = {
    {{3, 2, 1, 0, 0}, {7, 6, 5, 4, 0}},
    {{5, 1, 4, 0, 1}, {7, 3, 6, 2, 1}},
    {{6, 4, 2, 0, 2}, {7, 5, 3, 1, 2}},
};

const int processEdgeMask[3][4] = {
    {3, 2, 1, 0},
    {7, 5, 6, 4},
    {11, 10, 9, 8},
};

const int dirCell[3][4][3] = {{{0, -1, -1}, {0, -1, 0}, {0, 0, -1}, {0, 0, 0}},
                              {{-1, 0, -1}, {-1, 0, 0}, {0, 0, -1}, {0, 0, 0}},
                              {{-1, -1, 0}, {-1, 0, 0}, {0, -1, 0}, {0, 0, 0}}};

const int dirEdge[3][4] = {
    {3, 2, 1, 0},
    {7, 6, 5, 4},
    {11, 10, 9, 8},
};

int InternalNode::numChildrenTable[256];
int InternalNode::childrenCountTable[256][8];
int InternalNode::childrenIndexTable[256][8];
