v -126.4800033569 12.4945001602 -173.8119964600
v -126.6900024414 21.4505004883 -170.0980072021
v -108.1169967651 -28.3661003113 -170.7310028076
f 1 2 3

void ReadOBJ(const std::string &obj_file,
             std::vector<double> &vert_pos,
             std::vector<int> &tri_ind){
  tinyobj::attrib_t attrib;
  std::vector<tinyobj::shape_t> shapes;
  std::vector<tinyobj::material_t> materials;
  std::string warn;
  std::string err;

  tinyobj::LoadObj(&attrib, &shapes, &materials, &warn, &err, obj_file.c_str());

  for (double vertice : attrib.vertices){
    vert_pos.emplace_back(vertice);

    std::cout << vertice << std::endl;
  }

  for (auto &shape : shapes){
    for (auto &indice : shape.mesh.indices){
      tri_ind.emplace_back(indice.vertex_index);
    }
  }
}

int main(){
  std::vector<double> vert_pos;
  std::vector<int> tri_ind;

  ReadOBJ("test.obj", vert_pos, tri_ind);

  std::cout << "total verts: " << vert_pos.size() << std::endl;
  return 0;
}

3.68883e+19
-3.49406
1.08357e-19
2.64045
-3.68995e+19
-3.58948
-nan
-3.49488
7.39465e-42
2.83516
-3.68897e+19
-3.58222
-3.68878e+19
-3.42233
-2.00139
-2.94322
3.68922e+19
-3.58346
total verts: 18

-126.48
12.4945
-173.812
-126.69
21.4505
-170.098
-108.117
-28.3661
-170.731
total verts: 9