font_hashing.cpp

struct Font
{
  std::string name;
  uint16_t size;
  bool is_bold;
  bool is_italic;
};

bool operator==(const Font& f1, const Font& f2)
{
  return 
    f1.name == f2.name &&
    f1.size == f2.size &&
    f1.is_bold == f2.is_bold &&
    f1.is_italic == f2.is_italic;
}

uint32_t djb2(const std::string& text) { return 0 /* TODO */; }

namespace std {

  template <>
  struct hash<Font>
  {
    std::size_t operator()(const Font& font) const
    {
      int64_t hash = djb2(font.name);
      hash |= (static_cast<uint64_t>(font.size) << 32);
      hash |= (static_cast<uint64_t>(font.is_bold)) << 48;
      hash |= (static_cast<uint64_t>(font.is_bold)) << 56;
      
      return static_cast<std::size_t>(hash);
    }
  };
}