model.cpp

#include <fstream>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>

#include "./model.h"

std::vector<std::string> splitString(const std::string& input, char delimiter) {
  std::vector<std::string> content;
  std::stringstream line(input);
  std::string temp;

  while (std::getline(line, temp, delimiter)) {
    content.push_back(temp);
  }

  return content;
}

Model::Model(const std::string filename) {
  std::ifstream file(filename);
  if (!file) {
    std::cout << "File cannot be opened!" << std::endl;
  }
  std::string line;
  while (getline(file, line)) {
    if (line.empty()) continue;
    std::vector<std::string> content = splitString(line, ' ');
    if (content.at(0) == "v") {
      vec3 vertex = {std::stod(content.at(1)), std::stod(content.at(2)),
                     std::stod(content.at(3))};
      verts.push_back(vertex);
    } else if (content[0] == "f") {
      std::vector<std::string> contentFacesA = splitString(content[1], '/');
      std::vector<std::string> contentFacesB = splitString(content[2], '/');
      std::vector<std::string> contentFacesC = splitString(content[3], '/');
      // Decrement by ones because obj file indices start at 1
      facet_vrt.push_back(stoi(contentFacesA[0]) - 1);
      facet_vrt.push_back(stoi(contentFacesB[0]) - 1);
      facet_vrt.push_back(stoi(contentFacesC[0]) - 1);
    }
  }
}

int Model::nverts() const { return verts.size(); }
int Model::nfaces() const { return facet_vrt.size() / 3; }

vec3 Model::vert(const int i) const { return verts[i]; }

vec3 Model::vert(const int iface, const int nthvert) const {
  return verts[facet_vrt[iface * 3 + nthvert]];
}