Tracking/ITSTGeoImport/translation.cxx

0001 #include <vector>
0002
0003 void init()
0004 {
0005     gSystem->Load("libGeom");
0006     TGeoManager::Import("ALICE_ITS_tgeo.root");
0007 }
0008
0009 std::vector<TGeoNode*> path;
0010 bool nodeFound = false;
0011 void getNode(TString name)
0012 {
0013     nodeFound = false;
0014     path.clear();
0015
0016     dfs(gGeoManager->GetTopNode(), name);
0017
0018     cout << "Node path: ";
0019     for(int i = 0; i < path.size(); ++i)
0020     {
0021         cout << path[i]->GetName() << " ";
0022     }
0023     cout << endl;
0024 }
0025
0026 void dfs(TGeoNode* node, TString name)
0027 {
0028     //if(nodeFound) return;
0029
0030     path.push_back(node);
0031     if(node->GetName() == name)
0032     {
0033         nodeFound = true;
0034         return;
0035     }
0036
0037     for(int i = 0; i < node->GetNdaughters(); ++i)
0038     {
0039         dfs(node->GetDaughter(i), name);
0040         if(nodeFound) return;
0041     }
0042     path.pop_back();
0043 }
0044
0045 void translation(TString name, TString mothername = "")
0046 {
0047     //Get the node and path from world
0048     getNode(name);
0049
0050     //Get mother node index
0051     int idx_mother = -1;
0052     if(mothername == "")
0053     {
0054         idx_mother = 0;
0055     }
0056     else
0057     {
0058         for(int i = 0; i < path.size(); ++i)
0059         {
0060             if(path[i]->GetName() == mothername)
0061             {
0062                 idx_mother = i;
0063                 break;
0064             }
0065         }
0066     }
0067
0068     //Get the transformation matrix level-by-level
0069     TGeoHMatrix mat;
0070     for(int i = idx_mother+1; i < path.size(); ++i)
0071     {
0072         mat *= (*path[i]->GetMatrix());
0073     }
0074
0075     cout << "Translation from " << name << " to " << mothername << endl;
0076     mat.Print();
0077 }