Face.cpp

#include "Face.hpp"

using namespace std;
 
Face::Face(vector<Vector3D> const& vert,size_t neighbor1,size_t neighbor2):
  vertices(vert),neighbors(neighbor1,neighbor2) {}

Face::Face(void): vertices(), neighbors() {}

Face& Face::operator=(const Face& other)
{
  vertices = other.vertices;
  neighbors = other.neighbors;
  return *this;
}

  Face::~Face(void)
  {}

Face::Face(Face const& other):
  vertices(other.vertices),
  neighbors(other.neighbors) {}

  double Face::GetArea(void) const
  {
          double res=0;
          for(size_t i=0;i<vertices.size()-2;++i)
                  res+=0.5*abs(CrossProduct(vertices[i+1]-vertices[0],vertices[i+2]-vertices[0]));
          return res;
  }

Vector3D calc_centroid(const Face& face)
{
        Vector3D res;
        for(size_t i=0;i<face.vertices.size()-2;++i)
        {
                double area=0.5*abs(CrossProduct(face.vertices[i+1]-face.vertices[0],
                        face.vertices[i+2]-face.vertices[0]));
                res.x+=area*(face.vertices[0].x+face.vertices[i+2].x+face.vertices[i+1].x)/3.;
                res.y+=area*(face.vertices[0].y+face.vertices[i+2].y+face.vertices[i+1].y)/3.;
                res.z+=area*(face.vertices[0].z+face.vertices[i+2].z+face.vertices[i+1].z)/3.;
        }
        return res;
}