RGeomData.cxx

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// @(#)root/eve7:$Id$
// Author: Sergey Linev, 14.12.2018
 
/*************************************************************************
 * Copyright (C) 1995-2019, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
 
#include <ROOT/RGeomData.hxx>
 
#include <ROOT/RBrowserRequest.hxx>
#include <ROOT/RBrowserReply.hxx>
#include <ROOT/RLogger.hxx>
#include "CsgOps.h"
 
#include "TMath.h"
#include "TColor.h"
#include "TROOT.h"
#include "TGeoNode.h"
#include "TGeoVolume.h"
#include "TGeoBBox.h"
#include "TGeoManager.h"
#include "TGeoMatrix.h"
#include "TGeoMedium.h"
#include "TGeoMaterial.h"
#include "TGeoBoolNode.h"
#include "TGeoCompositeShape.h"
#include "TBuffer3D.h"
#include "TBufferJSON.h"
 
#include <algorithm>
 
namespace ROOT {
namespace Experimental {
 
 
RLogChannel &RGeomLog()
{
   static RLogChannel sLog("ROOT.Geom");
   return sLog;
}
 
 
/** Iterator of hierarchical geometry structures */
 
class RGeomBrowserIter {
 
   RGeomDescription &fDesc;
   int fParentId{-1};
   unsigned fChild{0};
   int fNodeId{0};
 
   std::vector<int> fStackParents;
   std::vector<int> fStackChilds;
 
public:
 
   RGeomBrowserIter(RGeomDescription &desc) : fDesc(desc) {}
 
   const std::string &GetName() const { return fDesc.fDesc[fNodeId].name; }
 
   bool IsValid() const { return fNodeId >= 0; }
 
   int GetNodeId() const { return fNodeId; }
 
   bool HasChilds() const { return (fNodeId < 0) ? true : fDesc.fDesc[fNodeId].chlds.size() > 0; }
 
   int NumChilds() const { return (fNodeId < 0) ? 1 : fDesc.fDesc[fNodeId].chlds.size(); }
 
   bool Enter()
   {
      if (fNodeId < 0) {
         Reset();
         fNodeId = 0;
         return true;
      }
 
      if (fNodeId >= (int) fDesc.fDesc.size())
         return false;
 
      auto &node = fDesc.fDesc[fNodeId];
      if (node.chlds.size() == 0) return false;
      fStackParents.emplace_back(fParentId);
      fStackChilds.emplace_back(fChild);
      fParentId = fNodeId;
      fChild = 0;
      fNodeId = node.chlds[fChild];
      return true;
   }
 
   bool Leave()
   {
      if (fStackParents.size() == 0) {
         fNodeId = -1;
         return false;
      }
      fParentId = fStackParents.back();
      fChild = fStackChilds.back();
 
      fStackParents.pop_back();
      fStackChilds.pop_back();
 
      if (fParentId < 0) {
         fNodeId = 0;
      } else {
         fNodeId = fDesc.fDesc[fParentId].chlds[fChild];
      }
      return true;
   }
 
   bool Next()
   {
      // does not have parents
      if ((fNodeId <= 0) || (fParentId < 0)) {
         Reset();
         return false;
      }
 
      auto &prnt = fDesc.fDesc[fParentId];
      if (++fChild >= prnt.chlds.size()) {
         fNodeId = -1; // not valid node, only Leave can be called
         return false;
      }
 
      fNodeId = prnt.chlds[fChild];
      return true;
   }
 
   bool Reset()
   {
      fParentId = -1;
      fNodeId = -1;
      fChild = 0;
      fStackParents.clear();
      fStackChilds.clear();
 
      return true;
   }
 
   bool NextNode()
   {
      if (Enter()) return true;
 
      if (Next()) return true;
 
      while (Leave()) {
         if (Next()) return true;
      }
 
      return false;
   }
 
   /** Navigate to specified path - path specified as string and should start with "/" */
   bool Navigate(const std::string &path)
   {
      size_t pos = path.find("/");
      if (pos != 0) return false;
 
      Reset(); // set to the top of element
 
      while (++pos < path.length()) {
         auto last = pos;
 
         pos = path.find("/", last);
 
         if (pos == std::string::npos) pos = path.length();
 
         std::string folder = path.substr(last, pos-last);
 
         if (!Enter()) return false;
 
         bool find = false;
 
         do {
            find = (folder.compare(GetName()) == 0);
         } while (!find && Next());
 
         if (!find) return false;
      }
 
      return true;
   }
 
   /** Navigate to specified path  */
   bool Navigate(const std::vector<std::string> &path)
   {
      Reset(); // set to the top of element
 
      for (auto &folder : path) {
 
         if (!Enter()) return false;
 
         bool find = false;
 
         do {
            find = (folder.compare(GetName()) == 0);
         } while (!find && Next());
 
         if (!find) return false;
      }
 
      return true;
   }
 
 
   /// Returns array of ids to currently selected node
   std::vector<int> CurrentIds() const
   {
      std::vector<int> res;
      if (IsValid()) {
         for (unsigned n=1;n<fStackParents.size();++n)
            res.emplace_back(fStackParents[n]);
         if (fParentId >= 0) res.emplace_back(fParentId);
         res.emplace_back(fNodeId);
      }
      return res;
   }
 
};
} // namespace Experimental
} // namespace ROOT
 
 
using namespace ROOT::Experimental;
 
using namespace std::string_literals;
 
/////////////////////////////////////////////////////////////////////
/// Pack matrix into vector, which can be send to client
/// Following sizes can be used for vector:
///   0 - Identity matrix
///   3 - Translation
///   4 - Scale (last element always 1)
///   9 - Rotation
///  16 - Full size
 
void RGeomDescription::PackMatrix(std::vector<float> &vect, TGeoMatrix *matr)
{
   vect.clear();
 
   if (!matr || matr->IsIdentity())
      return;
 
   auto trans = matr->GetTranslation();
   auto scale = matr->GetScale();
   auto rotate = matr->GetRotationMatrix();
 
   bool is_translate = matr->IsA() == TGeoTranslation::Class(),
        is_scale = matr->IsA() == TGeoScale::Class(),
        is_rotate = matr->IsA() == TGeoRotation::Class();
 
   if (!is_translate && !is_scale && !is_rotate) {
      // check if trivial matrix
 
      auto test = [](double val, double chk) { return (val==chk) || (TMath::Abs(val-chk) < 1e-20); };
 
      bool no_scale = test(scale[0],1) && test(scale[1],1) && test(scale[2],1);
      bool no_trans = test(trans[0],0) && test(trans[1],0) && test(trans[2],0);
      bool no_rotate = test(rotate[0],1) && test(rotate[1],0) && test(rotate[2],0) &&
                       test(rotate[3],0) && test(rotate[4],1) && test(rotate[5],0) &&
                       test(rotate[6],0) && test(rotate[7],0) && test(rotate[8],1);
 
      if (no_scale && no_trans && no_rotate)
         return;
 
      if (no_scale && no_trans && !no_rotate) {
         is_rotate = true;
      } else if (no_scale && !no_trans && no_rotate) {
         is_translate = true;
      } else if (!no_scale && no_trans && no_rotate) {
         is_scale = true;
      }
   }
 
   if (is_translate) {
      vect.resize(3);
      vect[0] = trans[0];
      vect[1] = trans[1];
      vect[2] = trans[2];
      return;
   }
 
   if (is_scale) {
      vect.resize(4);
      vect[0] = scale[0];
      vect[1] = scale[1];
      vect[2] = scale[2];
      vect[3] = 1;
      return;
   }
 
   if (is_rotate) {
      vect.resize(9);
      for (int n=0;n<9;++n)
         vect[n] = rotate[n];
      return;
   }
 
   vect.resize(16);
   vect[0] = rotate[0]; vect[4] = rotate[1]; vect[8]  = rotate[2]; vect[12] = trans[0];
   vect[1] = rotate[3]; vect[5] = rotate[4]; vect[9]  = rotate[5]; vect[13] = trans[1];
   vect[2] = rotate[6]; vect[6] = rotate[7]; vect[10] = rotate[8]; vect[14] = trans[2];
   vect[3] = 0;         vect[7] = 0;         vect[11] = 0;         vect[15] = 1;
}
 
/////////////////////////////////////////////////////////////////////
/// Collect information about geometry hierarchy into flat list
/// like it done in JSROOT ClonedNodes.createClones
 
void RGeomDescription::Build(TGeoManager *mgr, const std::string &volname)
{
   ClearDescription();
   if (!mgr) return;
 
   auto topnode = mgr->GetTopNode();
 
   if (!volname.empty()) {
      auto vol = mgr->GetVolume(volname.c_str());
      if (vol) {
         TGeoNode *node;
         TGeoIterator next(mgr->GetTopVolume());
         while ((node = next()) != nullptr) {
            if (node->GetVolume() == vol) break;
         }
         if (node) topnode = node;
      }
   }
 
   // by top node visibility always enabled and harm logic
   // later visibility can be controlled by other means
   // mgr->GetTopNode()->GetVolume()->SetVisibility(kFALSE);
 
   int maxnodes = mgr->GetMaxVisNodes();
 
   SetNSegments(mgr->GetNsegments());
   SetVisLevel(mgr->GetVisLevel());
   SetMaxVisNodes(maxnodes);
   SetMaxVisFaces( (maxnodes > 5000 ? 5000 : (maxnodes < 1000 ? 1000 : maxnodes)) * 100);
 
   BuildDescription(topnode, topnode->GetVolume());
}
 
/////////////////////////////////////////////////////////////////////
/// Collect information about geometry from single volume
/// like it done in JSROOT ClonedNodes.createClones
 
void RGeomDescription::Build(TGeoVolume *vol)
{
   ClearDescription();
 
   if (!vol) return;
 
   fDrawVolume = vol;
 
   BuildDescription(nullptr, fDrawVolume);
}
 
/////////////////////////////////////////////////////////////////////
/// Clear geometry description
 
void RGeomDescription::ClearDescription()
{
   fDesc.clear();
   fNodes.clear();
   fSortMap.clear();
   ClearDrawData();
   fDrawIdCut = 0;
   fDrawVolume = nullptr;
}
 
/////////////////////////////////////////////////////////////////////
/// Build geometry description
 
void RGeomDescription::BuildDescription(TGeoNode *topnode, TGeoVolume *topvolume)
{
   // vector to remember numbers
   std::vector<int> numbers;
   int offset = 1000000000;
 
   // try to build flat list of all nodes
   TGeoNode *snode = topnode;
   TGeoIterator iter(topvolume);
   do {
      if (!snode) {
         numbers.emplace_back(offset);
         fNodes.emplace_back(nullptr);
      } else if (snode->GetNumber() >= offset) {
         // artificial offset already applied, used as identifier
         iter.Skip(); // no need to look inside
      } else {
         numbers.emplace_back(snode->GetNumber());
         snode->SetNumber(offset + fNodes.size()); // use id with shift 1e9
         fNodes.emplace_back(snode);
      }
   } while ((snode = iter()) != nullptr);
 
   fDesc.reserve(fNodes.size());
   numbers.reserve(fNodes.size());
   fSortMap.reserve(fNodes.size());
 
   // array for sorting
   std::vector<RGeomNode *> sortarr;
   sortarr.reserve(fNodes.size());
 
   // create vector of desc and childs
   int cnt = 0;
   for (auto node : fNodes) {
 
      fDesc.emplace_back(node ? node->GetNumber() - offset : 0);
      TGeoVolume *vol = node ? node->GetVolume() : topvolume;
 
      auto &desc = fDesc[cnt++];
 
      sortarr.emplace_back(&desc);
 
      desc.name = node ? node->GetName() : vol->GetName();
 
      auto shape = dynamic_cast<TGeoBBox *>(vol->GetShape());
      if (shape) {
         desc.vol = shape->GetDX() * shape->GetDY() * shape->GetDZ();
         desc.nfaces = 12; // TODO: get better value for each shape - excluding composite
      }
 
      CopyMaterialProperties(vol, desc);
 
      auto chlds = node ? node->GetNodes() : vol->GetNodes();
 
      PackMatrix(desc.matr, node ? node->GetMatrix() : nullptr);
 
      if (chlds)
         for (int n = 0; n <= chlds->GetLast(); ++n) {
            auto chld = dynamic_cast<TGeoNode *> (chlds->At(n));
            desc.chlds.emplace_back(chld->GetNumber() - offset);
         }
   }
 
   // recover numbers
   cnt = 0;
   for (auto node : fNodes) {
      auto number = numbers[cnt++];
      if (node) node->SetNumber(number);
   }
 
   // sort in volume descent order
   std::sort(sortarr.begin(), sortarr.end(), [](RGeomNode *a, RGeomNode * b) { return a->vol > b->vol; });
 
   cnt = 0;
   for (auto &elem: sortarr) {
      fSortMap.emplace_back(elem->id);
      elem->sortid = cnt++; // keep place in sorted array to correctly apply cut
   }
 
   MarkVisible(); // set visibility flags
 
   ProduceIdShifts();
}
 
/////////////////////////////////////////////////////////////////////
/// Get volume for specified nodeid
/// If specific volume was configured, it will be returned for nodeid==0
 
TGeoVolume *RGeomDescription::GetVolume(int nodeid)
{
   auto node = fNodes[nodeid];
   if (node) return node->GetVolume();
   return nodeid == 0 ? fDrawVolume : nullptr;
}
 
/////////////////////////////////////////////////////////////////////
/// Set visibility flag for each nodes
 
int RGeomDescription::MarkVisible(bool on_screen)
{
   int res = 0;
   for (int nodeid = 0; nodeid < (int) fNodes.size(); nodeid++) {
 
      auto node = fNodes[nodeid];
      auto vol = GetVolume(nodeid);
      auto &desc = fDesc[nodeid];
      desc.vis = 0;
      desc.nochlds = false;
 
      if (on_screen) {
         if (!node || node->IsOnScreen())
            desc.vis = 99;
      } else {
         if (vol->IsVisible() && !vol->TestAttBit(TGeoAtt::kVisNone))
            desc.vis = 99;
 
         if (node && !node->IsVisDaughters())
            desc.nochlds = true;
 
         if ((desc.vis > 0) && (desc.chlds.size() > 0) && !desc.nochlds)
            desc.vis = 1;
      }
 
      if (desc.IsVisible() && desc.CanDisplay()) res++;
   }
 
   return res;
}
 
/////////////////////////////////////////////////////////////////////
/// Count total number of visible childs under each node
 
void RGeomDescription::ProduceIdShifts()
{
   for (auto &node : fDesc)
      node.idshift = -1;
 
   using ScanFunc_t = std::function<int(RGeomNode &)>;
 
   ScanFunc_t scan_func = [&, this](RGeomNode &node) {
      if (node.idshift < 0) {
         node.idshift = 0;
         for(auto id : node.chlds)
            node.idshift += scan_func(fDesc[id]);
      }
 
      return node.idshift + 1;
   };
 
   if (fDesc.size() > 0)
      scan_func(fDesc[0]);
}
 
/////////////////////////////////////////////////////////////////////
/// Iterate over all nodes and call function for visible
 
int RGeomDescription::ScanNodes(bool only_visible, int maxlvl, RGeomScanFunc_t func)
{
   if (fDesc.empty()) return 0;
 
   std::vector<int> stack;
   stack.reserve(25); // reserve enough space for most use-cases
   int counter = 0;
 
   using ScanFunc_t = std::function<int(int, int)>;
 
   ScanFunc_t scan_func = [&, this](int nodeid, int lvl) {
      auto &desc = fDesc[nodeid];
      int res = 0;
 
      if (desc.nochlds && (lvl > 0)) lvl = 0;
 
      // same logic as in JSROOT ClonedNodes.scanVisible
      bool is_visible = (lvl >= 0) && (desc.vis > lvl) && desc.CanDisplay();
 
      if (is_visible || !only_visible)
         if (func(desc, stack, is_visible, counter))
            res++;
 
      counter++; // count sequence id of current position in scan, will be used later for merging drawing lists
 
      if ((desc.chlds.size() > 0) && ((lvl > 0) || !only_visible)) {
         auto pos = stack.size();
         stack.emplace_back(0);
         for (unsigned k = 0; k < desc.chlds.size(); ++k) {
            stack[pos] = k; // stack provides index in list of childs
            res += scan_func(desc.chlds[k], lvl - 1);
         }
         stack.pop_back();
      } else {
         counter += desc.idshift;
      }
 
      return res;
   };
 
   if (!maxlvl && (GetVisLevel() > 0)) maxlvl = GetVisLevel();
   if (!maxlvl) maxlvl = 4;
   if (maxlvl > 97) maxlvl = 97; // check while vis property of node is 99 normally
 
   return scan_func(0, maxlvl);
}
 
/////////////////////////////////////////////////////////////////////
/// Collect nodes which are used in visibles
 
void RGeomDescription::CollectNodes(RGeomDrawing &drawing)
{
   // TODO: for now reset all flags, later can be kept longer
   for (auto &node : fDesc)
      node.useflag = false;
 
   drawing.cfg = &fCfg;
 
   drawing.numnodes = fDesc.size();
 
   for (auto &item : drawing.visibles) {
      int nodeid = 0;
      for (auto &chindx : item.stack) {
         auto &node = fDesc[nodeid];
         if (!node.useflag) {
            node.useflag = true;
            drawing.nodes.emplace_back(&node);
         }
         if (chindx >= (int)node.chlds.size())
            break;
         nodeid = node.chlds[chindx];
      }
 
      auto &node = fDesc[nodeid];
      if (!node.useflag) {
         node.useflag = true;
         drawing.nodes.emplace_back(&node);
      }
   }
 
   // printf("SELECT NODES %d\n", (int) drawing.nodes.size());
}
 
/////////////////////////////////////////////////////////////////////
/// Find description object for requested shape
/// If not exists - will be created
 
std::string RGeomDescription::ProcessBrowserRequest(const std::string &msg)
{
   std::string res;
 
   auto request = TBufferJSON::FromJSON<RBrowserRequest>(msg);
 
   if (msg.empty()) {
      request = std::make_unique<RBrowserRequest>();
      request->first = 0;
      request->number = 100;
   }
 
   if (!request)
      return res;
 
   if (request->path.empty() && (request->first == 0) && (GetNumNodes() < (IsPreferredOffline() ? 1000000 : 1000))) {
 
      std::vector<RGeomNodeBase *> vect(fDesc.size(), nullptr);
 
      int cnt = 0;
      for (auto &item : fDesc)
         vect[cnt++]= &item;
 
      res = "DESCR:"s + TBufferJSON::ToJSON(&vect,GetJsonComp()).Data();
   } else {
      std::vector<Browsable::RItem> temp_nodes;
      bool toplevel = request->path.empty();
 
      // create temporary object for the short time
      RBrowserReply reply;
      reply.path = request->path;
      reply.first = request->first;
 
      RGeomBrowserIter iter(*this);
      if (iter.Navigate(request->path)) {
 
         reply.nchilds = iter.NumChilds();
         // scan childs of selected nodes
         if (iter.Enter()) {
 
            while ((request->first > 0) && iter.Next()) {
               request->first--;
            }
 
            while (iter.IsValid() && (request->number > 0)) {
               temp_nodes.emplace_back(iter.GetName(), iter.NumChilds());
               if (toplevel) temp_nodes.back().SetExpanded(true);
               request->number--;
               if (!iter.Next()) break;
            }
         }
      }
 
      for (auto &n : temp_nodes)
         reply.nodes.emplace_back(&n);
 
      res = "BREPL:"s + TBufferJSON::ToJSON(&reply, GetJsonComp()).Data();
   }
 
   return res;
}
 
/////////////////////////////////////////////////////////////////////
/// Find description object for requested shape
/// If not exists - will be created
 
RGeomDescription::ShapeDescr &RGeomDescription::FindShapeDescr(TGeoShape *shape)
{
   for (auto &descr : fShapes)
      if (descr.fShape == shape)
         return descr;
 
   fShapes.emplace_back(shape);
   auto &elem = fShapes.back();
   elem.id = fShapes.size() - 1;
   return elem;
}
 
 
////////////////////////////////////////////////////////////////////////
/// Function produces mesh for provided shape, applying matrix to the result
 
std::unique_ptr<RootCsg::TBaseMesh> MakeGeoMesh(TGeoMatrix *matr, TGeoShape *shape)
{
   TGeoCompositeShape *comp = dynamic_cast<TGeoCompositeShape *> (shape);
 
   std::unique_ptr<RootCsg::TBaseMesh> res;
 
   if (!comp) {
      std::unique_ptr<TBuffer3D> b3d(shape->MakeBuffer3D());
 
      if (matr) {
         Double_t *v = b3d->fPnts;
         Double_t buf[3];
         for (UInt_t i = 0; i < b3d->NbPnts(); ++i) {
            buf[0] = v[i*3];
            buf[1] = v[i*3+1];
            buf[2] = v[i*3+2];
            matr->LocalToMaster(buf, &v[i*3]);
         }
      }
 
      res.reset(RootCsg::ConvertToMesh(*b3d.get()));
   } else {
      auto node = comp->GetBoolNode();
 
      TGeoHMatrix mleft, mright;
      if (matr) { mleft = *matr; mright = *matr; }
 
      mleft.Multiply(node->GetLeftMatrix());
      auto left = MakeGeoMesh(&mleft, node->GetLeftShape());
 
      mright.Multiply(node->GetRightMatrix());
      auto right = MakeGeoMesh(&mright, node->GetRightShape());
 
      if (node->IsA() == TGeoUnion::Class()) res.reset(RootCsg::BuildUnion(left.get(), right.get()));
      if (node->IsA() == TGeoIntersection::Class()) res.reset(RootCsg::BuildIntersection(left.get(), right.get()));
      if (node->IsA() == TGeoSubtraction::Class()) res.reset(RootCsg::BuildDifference(left.get(), right.get()));
   }
 
   return res;
}
 
 
/////////////////////////////////////////////////////////////////////
/// Find description object and create render information
 
RGeomDescription::ShapeDescr &RGeomDescription::MakeShapeDescr(TGeoShape *shape)
{
   auto &elem = FindShapeDescr(shape);
 
   if (elem.nfaces == 0) {
 
      int boundary = 3; //
      if (shape->IsComposite()) {
         // composite is most complex for client, therefore by default build on server
         boundary = 1;
      } else if (!shape->IsCylType()) {
         // simple box geometry is compact and can be delivered as raw
         boundary = 2;
      }
 
      if (IsBuildShapes() < boundary) {
         elem.nfaces = 1;
         elem.fShapeInfo.shape = shape;
      } else {
 
         int old_nsegm = -1;
         if (fCfg.nsegm > 0 && gGeoManager) {
            old_nsegm = gGeoManager->GetNsegments();
            gGeoManager->SetNsegments(fCfg.nsegm);
         }
 
         auto mesh = MakeGeoMesh(nullptr, shape);
 
         if (old_nsegm > 0 && gGeoManager)
            gGeoManager->SetNsegments(old_nsegm);
 
 
         Int_t num_vertices = mesh->NumberOfVertices(), num_polynoms = 0;
 
         for (unsigned polyIndex = 0; polyIndex < mesh->NumberOfPolys(); ++polyIndex) {
 
            auto size_of_polygon = mesh->SizeOfPoly(polyIndex);
 
            if (size_of_polygon >= 3)
               num_polynoms += (size_of_polygon - 2);
         }
 
         Int_t index_buffer_size = num_polynoms * 3,  // triangle indexes
               vertex_buffer_size = num_vertices * 3; // X,Y,Z array
 
         elem.nfaces = num_polynoms;
 
         std::vector<float> vertices(vertex_buffer_size);
 
         for (Int_t i = 0; i < num_vertices; ++i) {
            auto v = mesh->GetVertex(i);
            vertices[i*3] = v[0];
            vertices[i*3+1] = v[1];
            vertices[i*3+2] = v[2];
         }
 
         elem.fRawInfo.raw.resize(vertices.size() * sizeof(float));
 
         memcpy(reinterpret_cast<char *>(elem.fRawInfo.raw.data()), vertices.data(), vertices.size() * sizeof(float));
 
         auto &indexes = elem.fRawInfo.idx;
 
         indexes.resize(index_buffer_size);
         int pos = 0;
 
         for (unsigned polyIndex = 0; polyIndex < mesh->NumberOfPolys(); ++polyIndex) {
            auto size_of_polygon = mesh->SizeOfPoly(polyIndex);
 
            // add first triangle
            if (size_of_polygon >= 3)
               for (int i = 0; i < 3; ++i)
                  indexes[pos++] = mesh->GetVertexIndex(polyIndex, i);
 
            // add following triangles
            if (size_of_polygon > 3)
               for (unsigned vertex = 3; vertex < size_of_polygon; vertex++) {
                  indexes[pos++] = mesh->GetVertexIndex(polyIndex, 0);
                  indexes[pos++] = mesh->GetVertexIndex(polyIndex, vertex-1);
                  indexes[pos++] = mesh->GetVertexIndex(polyIndex, vertex);
               }
         }
 
      }
   }
 
   return elem;
}
 
/////////////////////////////////////////////////////////////////////
/// Copy material properties
 
void RGeomDescription::CopyMaterialProperties(TGeoVolume *volume, RGeomNode &node)
{
   if (!volume) return;
 
   TColor *col{nullptr};
 
   if ((volume->GetFillColor() > 1) && (volume->GetLineColor() == 1))
      col = gROOT->GetColor(volume->GetFillColor());
   else if (volume->GetLineColor() >= 0)
      col = gROOT->GetColor(volume->GetLineColor());
 
   if (volume->GetMedium() && (volume->GetMedium() != TGeoVolume::DummyMedium()) && volume->GetMedium()->GetMaterial()) {
      auto material = volume->GetMedium()->GetMaterial();
 
      auto fillstyle = material->GetFillStyle();
      if ((fillstyle>=3000) && (fillstyle<=3100)) node.opacity = (3100 - fillstyle) / 100.;
      if (!col) col = gROOT->GetColor(material->GetFillColor());
   }
 
   if (col) {
      node.color = std::to_string((int)(col->GetRed()*255)) + "," +
                   std::to_string((int)(col->GetGreen()*255)) + "," +
                   std::to_string((int)(col->GetBlue()*255));
      if (node.opacity == 1.)
         node.opacity = col->GetAlpha();
   } else {
      node.color.clear();
   }
}
 
/////////////////////////////////////////////////////////////////////
/// Reset shape info, which used to pack binary data
 
void RGeomDescription::ResetRndrInfos()
{
   for (auto &s: fShapes)
      s.reset();
}
 
/////////////////////////////////////////////////////////////////////
/// Produce JSON string which can be directly used with `build`
/// function from JSROOT to create three.js model of configured geometry
///
/// Collect all information required to draw geometry on the client
/// This includes list of each visible nodes, meshes and matrixes
///
/// Example of usage:
///
/// void geom() {
///    auto f = TFile::Open("file_name.root");
///    auto vol = f->Get<TGeoVolume>("object_name");
///    ROOT::Experimental::RGeomDescription desc;
///    desc.Build(vol);
///    std::ofstream fout("geom.json");
///    fout << desc.ProduceJson();
///  }
///
///  In JSROOT one loads data from JSON file and call `build` function to
///  produce three.js model
 
std::string RGeomDescription::ProduceJson()
{
   std::vector<int> viscnt(fDesc.size(), 0);
 
   int level = GetVisLevel();
 
   // first count how many times each individual node appears
   int numnodes = ScanNodes(true, level, [&viscnt](RGeomNode &node, std::vector<int> &, bool, int) {
      viscnt[node.id]++;
      return true;
   });
 
   if (GetMaxVisNodes() > 0) {
      while ((numnodes > GetMaxVisNodes()) && (level > 1)) {
         level--;
         viscnt.assign(viscnt.size(), 0);
         numnodes = ScanNodes(true, level, [&viscnt](RGeomNode &node, std::vector<int> &, bool, int) {
            viscnt[node.id]++;
            return true;
         });
      }
   }
 
   fActualLevel = level;
   fDrawIdCut = 0;
 
   int totalnumfaces = 0, totalnumnodes = 0;
 
   //for (auto &node : fDesc)
   //   node.SetDisplayed(false);
 
   // build all shapes in volume decreasing order
   for (auto &sid: fSortMap) {
      fDrawIdCut++; //
      auto &desc = fDesc[sid];
 
      if ((viscnt[sid] <= 0) || (desc.vol <= 0)) continue;
 
      auto shape = GetVolume(sid)->GetShape();
      if (!shape) continue;
 
      // now we need to create TEveGeoPolyShape, which can provide all rendering data
      auto &shape_descr = MakeShapeDescr(shape);
 
      // should not happen, but just in case
      if (shape_descr.nfaces <= 0) {
         R__LOG_ERROR(RGeomLog()) << "No faces for the shape " << shape->GetName() << " class " << shape->ClassName();
         continue;
      }
 
      // check how many faces are created
      totalnumfaces += shape_descr.nfaces * viscnt[sid];
      if ((GetMaxVisFaces() > 0) && (totalnumfaces > GetMaxVisFaces())) break;
 
      // also avoid too many nodes
      totalnumnodes += viscnt[sid];
      if ((GetMaxVisNodes() > 0) && (totalnumnodes > GetMaxVisNodes())) break;
 
      // desc.SetDisplayed(true);
   }
 
   // finally we should create data for streaming to the client
   // it includes list of visible nodes and rawdata
 
   RGeomDrawing drawing;
   ResetRndrInfos();
   bool has_shape = false;
 
   ScanNodes(true, level, [&, this](RGeomNode &node, std::vector<int> &stack, bool, int seqid) {
      if (node.sortid < fDrawIdCut) {
         drawing.visibles.emplace_back(node.id, seqid, stack);
 
         auto &item = drawing.visibles.back();
         item.color = node.color;
         item.opacity = node.opacity;
 
         auto volume = GetVolume(node.id);
 
         auto &sd = MakeShapeDescr(volume->GetShape());
 
         item.ri = sd.rndr_info();
         if (sd.has_shape()) has_shape = true;
      }
      return true;
   });
 
   CollectNodes(drawing);
 
   return MakeDrawingJson(drawing, has_shape);
}
 
/////////////////////////////////////////////////////////////////////
/// Collect all information required to draw geometry on the client
/// This includes list of each visible nodes, meshes and matrixes
 
void RGeomDescription::ProduceDrawData()
{
   fDrawJson = "GDRAW:"s + ProduceJson();
}
 
/////////////////////////////////////////////////////////////////////
/// Clear raw data. Will be rebuild when next connection will be established
 
void RGeomDescription::ClearDrawData()
{
   fDrawJson.clear();
}
 
/////////////////////////////////////////////////////////////////////
/// return true when node used in main geometry drawing and does not have childs
/// for such nodes one could provide optimize toggling of visibility flags
 
bool RGeomDescription::IsPrincipalEndNode(int nodeid)
{
   if ((nodeid < 0) || (nodeid >= (int)fDesc.size()))
      return false;
 
   auto &desc = fDesc[nodeid];
 
   return (desc.sortid < fDrawIdCut) && desc.IsVisible() && desc.CanDisplay() && (desc.chlds.size()==0);
}
 
 
/////////////////////////////////////////////////////////////////////
/// Search visible nodes for provided name
/// If number of found elements less than 100, create description and shapes for them
/// Returns number of match elements
 
int RGeomDescription::SearchVisibles(const std::string &find, std::string &hjson, std::string &json)
{
   hjson.clear();
   json.clear();
 
   if (find.empty()) {
      hjson = "FOUND:RESET";
      return 0;
   }
 
   std::vector<int> nodescnt(fDesc.size(), 0), viscnt(fDesc.size(), 0);
 
   int nmatches = 0;
 
   auto match_func = [&find](RGeomNode &node) {
      return (node.vol > 0) && (node.name.compare(0, find.length(), find) == 0);
   };
 
   // first count how many times each individual node appears
   ScanNodes(false, 0, [&nodescnt,&viscnt,&match_func,&nmatches](RGeomNode &node, std::vector<int> &, bool is_vis, int) {
 
      if (match_func(node)) {
         nmatches++;
         nodescnt[node.id]++;
         if (is_vis) viscnt[node.id]++;
      };
      return true;
   });
 
   // do not send too much data, limit could be made configurable later
   if (nmatches==0) {
      hjson = "FOUND:NO";
      return nmatches;
   }
 
   if ((GetMaxVisNodes() > 0) && (nmatches > 10 * GetMaxVisNodes())) {
      hjson = "FOUND:Too many " + std::to_string(nmatches);
      return nmatches;
   }
 
   // now build all necessary shapes and check number of faces - not too many
 
   int totalnumfaces = 0, totalnumnodes = 0, scnt = 0;
   bool send_rawdata = true;
 
   // build all shapes in volume decreasing order
   for (auto &sid: fSortMap) {
      if (scnt++ < fDrawIdCut) continue; // no need to send most significant shapes
 
      if (viscnt[sid] == 0) continue; // this node is not used at all
 
      auto &desc = fDesc[sid];
      if ((viscnt[sid] <= 0) && (desc.vol <= 0)) continue;
 
      auto shape = GetVolume(sid)->GetShape();
      if (!shape) continue;
 
      // create shape raw data
      auto &shape_descr = MakeShapeDescr(shape);
 
      // should not happen, but just in case
      if (shape_descr.nfaces <= 0) {
         R__LOG_ERROR(RGeomLog()) << "No faces for the shape " << shape->GetName() << " class " << shape->ClassName();
         continue;
      }
 
      // check how many faces are created
      totalnumfaces += shape_descr.nfaces * viscnt[sid];
      if ((GetMaxVisFaces() > 0) && (totalnumfaces > GetMaxVisFaces())) { send_rawdata = false; break; }
 
      // also avoid too many nodes
      totalnumnodes += viscnt[sid];
      if ((GetMaxVisNodes() > 0) && (totalnumnodes > GetMaxVisNodes()))  { send_rawdata = false; break; }
   }
 
   // only for debug purposes - remove later
   // send_rawdata = false;
 
   // finally we should create data for streaming to the client
   // it includes list of visible nodes and rawdata (if there is enough space)
 
 
   std::vector<RGeomNodeBase> found_desc; ///<! hierarchy of nodes, used for search
   std::vector<int> found_map(fDesc.size(), -1);   ///<! mapping between nodeid - > foundid
 
   // these are only selected nodes to produce hierarchy
 
   found_desc.emplace_back(0);
   found_desc[0].vis = fDesc[0].vis;
   found_desc[0].name = fDesc[0].name;
   found_desc[0].color = fDesc[0].color;
   found_map[0] = 0;
 
   ResetRndrInfos();
 
   RGeomDrawing drawing;
   bool has_shape = true;
 
   ScanNodes(false, 0, [&, this](RGeomNode &node, std::vector<int> &stack, bool is_vis, int seqid) {
      // select only nodes which should match
      if (!match_func(node))
         return true;
 
      // add entries into hierarchy of found elements
      int prntid = 0;
      for (auto &s : stack) {
         int chldid = fDesc[prntid].chlds[s];
         if (found_map[chldid] <= 0) {
            int newid = found_desc.size();
            found_desc.emplace_back(newid); // potentially original id can be used here
            found_map[chldid] = newid; // re-map into reduced hierarchy
 
            found_desc.back().vis = fDesc[chldid].vis;
            found_desc.back().name = fDesc[chldid].name;
            found_desc.back().color = fDesc[chldid].color;
         }
 
         auto pid = found_map[prntid];
         auto cid = found_map[chldid];
 
         // now add entry into childs lists
         auto &pchlds = found_desc[pid].chlds;
         if (std::find(pchlds.begin(), pchlds.end(), cid) == pchlds.end())
            pchlds.emplace_back(cid);
 
         prntid = chldid;
      }
 
      // no need to add visibles
      if (!is_vis) return true;
 
      drawing.visibles.emplace_back(node.id, seqid, stack);
 
      // no need to transfer shape if it provided with main drawing list
      // also no binary will be transported when too many matches are there
      if (!send_rawdata || (node.sortid < fDrawIdCut)) {
         // do not include render data
         return true;
      }
 
      auto &item = drawing.visibles.back();
      auto volume = GetVolume(node.id);
 
      item.color = node.color;
      item.opacity = node.opacity;
 
      auto &sd = MakeShapeDescr(volume->GetShape());
 
      item.ri = sd.rndr_info();
      if (sd.has_shape()) has_shape = true;
      return true;
   });
 
   hjson = "FESCR:"s + TBufferJSON::ToJSON(&found_desc, GetJsonComp()).Data();
 
   CollectNodes(drawing);
 
   json = "FDRAW:"s + MakeDrawingJson(drawing, has_shape);
 
   return nmatches;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Returns nodeid for given stack array, returns -1 in case of failure
 
int RGeomDescription::FindNodeId(const std::vector<int> &stack)
{
   int nodeid = 0;
 
   for (auto &chindx: stack) {
      auto &node = fDesc[nodeid];
      if (chindx >= (int) node.chlds.size()) return -1;
      nodeid = node.chlds[chindx];
   }
 
   return nodeid;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Creates stack for given array of ids, first element always should be 0
 
std::vector<int> RGeomDescription::MakeStackByIds(const std::vector<int> &ids)
{
   std::vector<int> stack;
 
   if (ids[0] != 0) {
      printf("Wrong first id\n");
      return stack;
   }
 
   int nodeid = 0;
 
   for (unsigned k = 1; k < ids.size(); ++k) {
 
      int prntid = nodeid;
      nodeid = ids[k];
 
      if (nodeid >= (int) fDesc.size()) {
         printf("Wrong node id %d\n", nodeid);
         stack.clear();
         return stack;
      }
      auto &chlds = fDesc[prntid].chlds;
      auto pos = std::find(chlds.begin(), chlds.end(), nodeid);
      if (pos == chlds.end()) {
         printf("Wrong id %d not a child of %d - fail to find stack num %d\n", nodeid, prntid, (int) chlds.size());
         stack.clear();
         return stack;
      }
 
      stack.emplace_back(std::distance(chlds.begin(), pos));
   }
 
   return stack;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Produce stack based on string path
/// Used to highlight geo volumes by browser hover event
 
std::vector<int> RGeomDescription::MakeStackByPath(const std::vector<std::string> &path)
{
   std::vector<int> res;
 
   RGeomBrowserIter iter(*this);
 
   if (iter.Navigate(path))
      res = MakeStackByIds(iter.CurrentIds());
 
   return res;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Produce list of node ids for given stack
/// If found nodes preselected - use their ids
 
std::vector<int> RGeomDescription::MakeIdsByStack(const std::vector<int> &stack)
{
   std::vector<int> ids;
 
   ids.emplace_back(0);
   int nodeid = 0;
   bool failure = false;
 
   for (auto s : stack) {
      auto &chlds = fDesc[nodeid].chlds;
      if (s >= (int) chlds.size()) { failure = true; break; }
 
      ids.emplace_back(chlds[s]);
 
      nodeid = chlds[s];
   }
 
   if (failure) {
      printf("Fail to convert stack into list of nodes\n");
      ids.clear();
   }
 
   return ids;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Returns path string for provided stack
 
std::vector<std::string> RGeomDescription::MakePathByStack(const std::vector<int> &stack)
{
   std::vector<std::string> path;
 
   auto ids = MakeIdsByStack(stack);
   for (auto &id : ids)
      path.emplace_back(fDesc[id].name);
 
   return path;
}
 
 
/////////////////////////////////////////////////////////////////////////////////
/// Return string with only part of nodes description which were modified
/// Checks also volume
 
std::string RGeomDescription::ProduceModifyReply(int nodeid)
{
   std::vector<RGeomNodeBase *> nodes;
   auto vol = GetVolume(nodeid);
 
   // we take not only single node, but all there same volume is referenced
   // nodes.push_back(&fDesc[nodeid]);
 
   int id = 0;
   for (auto &desc : fDesc)
      if (GetVolume(id++) == vol)
         nodes.emplace_back(&desc);
 
   return "MODIF:"s + TBufferJSON::ToJSON(&nodes, GetJsonComp()).Data();
}
 
 
/////////////////////////////////////////////////////////////////////////////////
/// Produce shape rendering data for given stack
/// All nodes, which are referencing same shape will be transferred
/// Returns true if new render information provided
 
bool RGeomDescription::ProduceDrawingFor(int nodeid, std::string &json, bool check_volume)
{
   // only this shape is interesting
 
   TGeoVolume *vol = (nodeid < 0) ? nullptr : GetVolume(nodeid);
 
   if (!vol || !vol->GetShape()) {
      json.append("NO");
      return false;
   }
 
   RGeomDrawing drawing;
 
   ScanNodes(true, 0, [&, this](RGeomNode &node, std::vector<int> &stack, bool, int seq_id) {
      // select only nodes which reference same shape
 
      if (check_volume) {
         if (GetVolume(node.id) != vol) return true;
      } else {
         if (node.id != nodeid) return true;
      }
 
      drawing.visibles.emplace_back(node.id, seq_id, stack);
 
      auto &item = drawing.visibles.back();
 
      item.color = node.color;
      item.opacity = node.opacity;
      return true;
   });
 
   // no any visible nodes were done
   if (drawing.visibles.size()==0) {
      json.append("NO");
      return false;
   }
 
   ResetRndrInfos();
 
   bool has_shape = false, has_raw = false;
 
   auto &sd = MakeShapeDescr(vol->GetShape());
 
   // assign shape data
   for (auto &item : drawing.visibles) {
      item.ri = sd.rndr_info();
      if (sd.has_shape()) has_shape = true;
      if (sd.has_raw()) has_raw = true;
   }
 
   CollectNodes(drawing);
 
   json.append(MakeDrawingJson(drawing, has_shape));
 
   return has_raw || has_shape;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Produce JSON for the drawing
/// If TGeoShape appears in the drawing, one has to keep typeinfo
/// But in this case one can exclude several classes which are not interesting,
/// but appears very often
 
std::string RGeomDescription::MakeDrawingJson(RGeomDrawing &drawing, bool has_shapes)
{
   int comp = GetJsonComp();
 
   if (!has_shapes || (comp < TBufferJSON::kSkipTypeInfo))
      return TBufferJSON::ToJSON(&drawing, comp).Data();
 
   comp = comp % TBufferJSON::kSkipTypeInfo; // no typeinfo skipping
 
   TBufferJSON json;
   json.SetCompact(comp);
   json.SetSkipClassInfo(TClass::GetClass<RGeomDrawing>());
   json.SetSkipClassInfo(TClass::GetClass<RGeomNode>());
   json.SetSkipClassInfo(TClass::GetClass<RGeomVisible>());
   json.SetSkipClassInfo(TClass::GetClass<RGeomShapeRenderInfo>());
   json.SetSkipClassInfo(TClass::GetClass<RGeomRawRenderInfo>());
 
   return json.StoreObject(&drawing, TClass::GetClass<RGeomDrawing>()).Data();
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Change visibility for specified element
/// Returns true if changes was performed
 
bool RGeomDescription::ChangeNodeVisibility(int nodeid, bool selected)
{
   auto &dnode = fDesc[nodeid];
 
   auto vol = GetVolume(nodeid);
 
   // nothing changed
   if (vol->IsVisible() == selected)
      return false;
 
   dnode.vis = selected ? 99 : 0;
   vol->SetVisibility(selected);
   if (dnode.chlds.size() > 0) {
      if (selected) dnode.vis = 1; // visibility disabled when any child
      vol->SetVisDaughters(selected);
   }
 
   int id = 0;
   for (auto &desc: fDesc)
      if (GetVolume(id++) == vol)
         desc.vis = dnode.vis;
 
   ClearDrawData(); // after change raw data is no longer valid
 
   return true;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Change visibility for specified element
/// Returns true if changes was performed
 
std::unique_ptr<RGeomNodeInfo> RGeomDescription::MakeNodeInfo(const std::vector<std::string> &path)
{
   std::unique_ptr<RGeomNodeInfo> res;
 
   RGeomBrowserIter iter(*this);
 
   if (iter.Navigate(path)) {
 
      auto node = fNodes[iter.GetNodeId()];
 
      auto &desc = fDesc[iter.GetNodeId()];
 
      res = std::make_unique<RGeomNodeInfo>();
 
      res->path = path;
      res->node_name = node ? node->GetName() : "node_name";
      res->node_type = node ? node->ClassName() : "no class";
 
      auto vol = GetVolume(iter.GetNodeId());
 
      TGeoShape *shape = vol ? vol->GetShape() : nullptr;
 
      if (shape) {
         res->shape_name = shape->GetName();
         res->shape_type = shape->ClassName();
      }
 
      if (shape && desc.CanDisplay()) {
 
         auto &shape_descr = MakeShapeDescr(shape);
 
         res->ri = shape_descr.rndr_info(); // temporary pointer, can be used preserved for short time
      }
   }
 
   return res;
}
 
/////////////////////////////////////////////////////////////////////////////////
/// Change configuration by client
/// Returns true if any parameter was really changed
 
bool RGeomDescription::ChangeConfiguration(const std::string &json)
{
   auto cfg = TBufferJSON::FromJSON<RGeomConfig>(json);
   if (!cfg) return false;
 
   auto json1 = TBufferJSON::ToJSON(cfg.get());
   auto json2 = TBufferJSON::ToJSON(&fCfg);
 
   if (json1 == json2)
      return false;
 
   fCfg = *cfg; // use assign
 
   ClearDrawData();
 
   return true;
}