DGtal::MeshReader< TPoint > Struct Template Reference

#include <MeshReader.h>

Static Public Member Functions
static bool	importOFFFile (const std::string &filename, DGtal::MeshFromPoints< TPoint > &aMesh, bool invertVertexOrder=false) throw (DGtal::IOException)
static bool	importOFSFile (const std::string &filename, DGtal::MeshFromPoints< TPoint > &aMesh, bool invertVertexOrder=false, double scale=1.0) throw (DGtal::IOException)

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Detailed Description

template<typename TPoint>
struct DGtal::MeshReader< TPoint >

Aim: Defined to import OFF and OFS surface mesh. It allows to import a MeshFromPoints object and takes into accouts the optional color faces.

Description of class 'MeshReader'

The importation can be done automatically according the input file extension with the operator <<

Example of typical use: Add these include files:

#include "DGtal/shapes/fromPoints/MeshFromPoints.h"
#include "DGtal/io/readers/MeshReader.h"

And automatic import the MeshFromPoints through the filename extension:

  std::string filenameOFF = testPath + "samples/box.off";  
  MeshFromPoints<Point> a3DMesh;
  bool importOK = a3DMesh << filenameOFF;

Then you can also display the resulting with a Viewer3D:

 viewer.setLineColor(DGtal::Color(150,0,0,254));
 viewer << a3DMesh;
 viewer << Viewer3D::updateDisplay;

See also:

MeshFromPoints MeshWriter

Definition at line 89 of file MeshReader.h.

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Member Function Documentation

template<typename TPoint >

bool DGtal::MeshReader< TPoint >::importOFFFile ( const std::string &  filename, DGtal::MeshFromPoints< TPoint > &  aMesh, bool  invertVertexOrder = false  ) throw (DGtal::IOException)

inlinestatic

Main method to import OFF meshes file (Geomview Object File Format)

Parameters:

filename	the file name to import.
aMesh,:	(return) the mesh object to be imported.
invertVertexOrder,:	used to invert (default value=false) the order of imported points (important for normal orientation).

Returns:

an instance of the imported mesh: MeshFromPoint.

Definition at line 52 of file MeshReader.ih.

References DGtal::Trace::error(), and DGtal::trace.

Referenced by DGtal::operator<<().

{
  ifstream infile;
  DGtal::IOException dgtalio;
  try 
    {
      infile.open (aFilename.c_str(), ifstream::in);
    }
  catch( ... )
    {
      trace.error() << "MeshReader : can't open " << aFilename << endl;
      throw dgtalio;
    }
  string str;
  getline( infile, str );
  
  if ( ! infile.good() )
    {
      trace.error() << "MeshReader : can't read " << aFilename << endl;
      throw dgtalio;
    }
  if ( str.substr(0,3) != "OFF")
    {
      cerr <<"*" <<str<<"*"<< endl;
      trace.error() << "MeshReader : No OFF format in " << aFilename << endl;
      throw dgtalio;
    }
  
  // Processing comments
  do
    {
      getline( infile, str );
      if ( ! infile.good() ){
        trace.error() << "MeshReader : Invalid format in " << aFilename << endl;
        throw dgtalio;
      } 
    }
  while ( str[ 0 ] == '#' || str=="");
  istringstream str_in( str );
  int nbPoints, nbFaces, nbEdges;
  str_in >> nbPoints;
  str_in >> nbFaces;
  str_in >> nbEdges;

  // Reading mesh vertex 
  for(int i=0; i<nbPoints; i++){
    TPoint p;
    infile >> p[0];
    infile >> p[1];
    infile >> p[2];
    aMesh.addVertex(p);
    // Needed since a line can also contain vertex colors
    getline(infile, str);
  }
  
  // Reading mesh faces
  for(int i=0; i<nbFaces; i++){
    // Reading the number of face vertex
    unsigned int aNbFaceVertex;
    infile >> aNbFaceVertex;
    vector<unsigned int> aFace;
    for (unsigned int j=0; j< aNbFaceVertex; j++){
      unsigned int anIndex;
      infile >> anIndex;
      aFace.push_back(anIndex);
    }
    if( invertVertexOrder ){
      for(unsigned int j=0; j < aFace.size()/2; j++){
        unsigned int tmp=aFace.at(j);
        aFace.at(j)=aFace.at(aFace.size()-1-j);
        aFace.at(aFace.size()-1-j)=tmp;
      }
    }
    
    // Needed since a can also contain vertex colors
    getline(infile, str);
    // Contains colors:
    bool findValidColor=true;
    if(str!=""){
      istringstream inColor(str);
      double colorR, colorG, colorB, colorT;
      findValidColor=inColor.good();
      if(findValidColor && inColor.good()){
        inColor >> colorR;
      }
      findValidColor &=!inColor.fail();
      if(findValidColor && inColor.good()){
        inColor >> colorG;
      }
      findValidColor &=!inColor.fail();
      if(findValidColor && inColor.good()){
        inColor >> colorB;
      }
      findValidColor &=!inColor.fail();
      
      if(findValidColor && inColor.good()){
        inColor >> colorT;
        // Since alpha is optional:
        if(inColor.fail()){
          colorT=1.0;
        }

      }else{
        colorT=1.0;
      }
      if(findValidColor){
        DGtal::Color c((unsigned int)(colorR*255.0), (unsigned int)(colorG*255.0),
                       (unsigned int)(colorB*255.0), (unsigned int)(colorT*255.0));
        aMesh.addFace(aFace, c);
      }else{
        aMesh.addFace(aFace);
      }
    }else{
      aMesh.addFace(aFace);
    }
  }
  
  return true;
}

template<typename TPoint >

bool DGtal::MeshReader< TPoint >::importOFSFile ( const std::string &  filename, DGtal::MeshFromPoints< TPoint > &  aMesh, bool  invertVertexOrder = false, double  scale = 1.0  ) throw (DGtal::IOException)

inlinestatic

Main method to import OFS meshes file (an equivalent of OFF format)

Parameters:

filename	the file name to import.
aMesh,:	(return) the mesh object to be imported.
invertVertexOrder,:	used to invert (default value=false) the order of imported points (important for normal orientation).
scale,:	used to avoid to display tiny shapes (since OFS shapes are generally included in a 1x1x1 cube)

Returns:

an instance of the imported mesh: MeshFromPoint.

Definition at line 182 of file MeshReader.ih.

References DGtal::Trace::error(), and DGtal::trace.

Referenced by DGtal::operator<<().

{
  ifstream infile;
  DGtal::IOException dgtalio;
  try 
    {
      infile.open (aFilename.c_str(), ifstream::in);
    }
  catch( ... )
    {
      trace.error() << "MeshReader : can't open " << aFilename << endl;
      throw dgtalio;
    }
  string str;
  getline( infile, str );
  
  if ( ! infile.good() )
    {
      trace.error() << "MeshReader : can't read " << aFilename << endl;
      throw dgtalio;
    }
  if ( str.substr(0,3) != "OFS")
    {
      trace.error() << "MeshReader : No OFS format in " << aFilename << endl;
      throw dgtalio;
    }
  
  // Processing comments
  do
    {
      getline( infile, str );
      if ( ! infile.good() ){
        trace.error() << "MeshReader : Invalid format in " << aFilename << endl;
        throw dgtalio;
      } 
    }
  while ( str[ 0 ] == '#' || str=="");
  istringstream str_in( str );
  int nbPoints;
  str_in >> nbPoints;
  
  // Reading mesh vertex 
  for(int i=0; i<nbPoints; i++){
    TPoint p;
    infile >> p[0];
    infile >> p[1];
    infile >> p[2];
    p[0]*=scale;
    p[1]*=scale;
    p[2]*=scale;
    aMesh.addVertex(p);
    // Needed since a line can also contain vertex colors
    getline(infile, str);
  }
  do
    {
      getline( infile, str );
      if ( ! infile.good() ){
        trace.error() << "MeshReader : Invalid format in " << aFilename << endl;
        throw dgtalio;
      } 
    }
  while ( str[ 0 ] == '#' || str=="");
  istringstream str_in2( str );
  unsigned int nbFaces;
  str_in2 >> nbFaces;
  // Reading mesh faces
  for(unsigned int i=0; i<nbFaces; i++){
    // Reading the number of face vertex
    vector<unsigned int> aFace;
    for (unsigned int j=0; j< 3; j++){
      unsigned int anIndex;
      infile >> anIndex;
      aFace.push_back(anIndex);
    }
    if( invertVertexOrder ){
      unsigned int tmp=aFace.at(0);
        aFace.at(0)=aFace.at(2);
        aFace.at(2)=tmp;
    }
    aMesh.addFace(aFace);
    getline(infile, str);
          
  }

  return true;
   
}

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The documentation for this struct was generated from the following files:

• MeshReader.h
• MeshReader.ih