Store information from a File in a Class object (C++) -

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i want read in input file class object using c++.

here class object trying read file input array had problems reading in lines after "polygon" keyword.

 class polygon{    public:   int object_number;   float point_count;   float px[size][size];   float py[size][size];   float pz[size][size];   float nx[size], ny[size], nz[size];     }; 

i want able store information after polygon keyword until next polygon keyword.

so, first polygon in file.

  object_number = 0;      point_count = 4;     px[0][0] = 100;  py[0][0]= 100;  pz[0][0] = 200;  nx[0][0] = 0.398925;  ny[0][0] =0.598388;  nz[0][0] = -0.453324;  

and forth until reaches next "poylgon" keyword in file. i'm going use information perform phong shading calculations

the file contains.

polygon 0 4 100 100 200 0.398925 0.598388 -0.453324 125 100 178 0.352837 0.646868 -0.490051 125 125 145 0.396981 0.595472 -0.551363 100 125 167 0.448836 0.550844 -0.510041 polygon 1 4 100 125 167 0.448836 0.550844 -0.510041 125 125 145 0.396981 0.595472 -0.551363 125 150 118 0.447405 0.521972 -0.621396 100 150 140 0.505846 0.482853 -0.574825 polygon 0 4 100 150 140 0.505846 0.482853 -0.574825 125 150 118 0.447405 0.521972 -0.621396 125 175 97 0.501037 0.417531 -0.695885 100 175 119 0.566484 0.386239 -0.643732 polygon 1 4 100 175 119 0.566484 0.386239 -0.643732 125 175 97 0.501037 0.417531 -0.695885 125 200 82 0.501037 0.417531 -0.695885 100 200 104 0.566484 0.386239 -0.643732    ....... 

unless have specific reason otherwise (such needing pass points gpu single block of memory), it's going lot easier break more manageable pieces.

class point {      float px, py, pz, nx, ny, nz;     // not sure order in file, may need fix this:     friend std::istream &operator>>(std::istream &is, point &p) {         return >> p.nx >> p.ny >> p.nz >> p.px >> p.py >> p.pz;     } };  class polygon {      int object_number;     std::vector<point> points;      friend std::istream &operator>>(std::istream &is, polygon &p) {          int point_count;         std::string check;         >> check;         if (check != "polygon") {            is.setstate(std::ios::failbit);            return is;         }         >> p.object_number >> point_count;         (int i=0; i<p.object_number; i++) {             point p2;             >> p2;             p.points.push_back(p2);         }         return is;     } }; 

from there, can read entire file full of polygons easily:

std::ifstream in("mypolygons.txt");  std::vector<polygon> polygons { std::istream_iterator<polygon>(in),                                 std::istream_iterator<polygon>() };