Хорошо, отправная точка для грамматики духа
_Name = "newmtl" >> lexeme [ +graph ];
_Ns = "Ns" >> double_;
_Ka = "Ka" >> double_ >> double_ >> double_;
_Kd = "Kd" >> double_ >> double_ >> double_;
_Ks = "Ks" >> double_ >> double_ >> double_;
_d = "d" >> double_;
_illum %= "illum" >> qi::int_ [ _pass = (_1>=0) && (_1<=10) ];
comment = '#' >> *(char_ - eol);
statement=
comment
| _Ns [ bind(&material::_Ns, _r1) = _1 ]
| _Ka [ bind(&material::_Ka, _r1) = _1 ]
| _Kd [ bind(&material::_Kd, _r1) = _1 ]
| _Ks [ bind(&material::_Ks, _r1) = _1 ]
| _d [ bind(&material::_d, _r1) = _1 ]
| _illum [ bind(&material::_illum, _r1) = _1 ]
;
_material = -comment % eol
>> _Name [ bind(&material::_Name, _val) = _1 ] >> eol
>> -statement(_val) % eol;
start = _material % -eol;
Я только реализованного подмножество грамматики MTL файла из файлов образцы.
Примечание: Это скорее упрощенная грамматика. Но, вы знаете, сначала первое. На самом деле я бы, вероятно, подумал об использовании the keyword list parser from the spirit repository. Он имеет возможности «требовать» определенного количества случаев для разных «типов полей».
Примечание: Духовная карма (и около ~ 50 других строк кода) предназначены только для демонстрационных целей.
Со следующим содержанием untitled.mtl
# Blender MTL File: 'None'
# Material Count: 2
newmtl None
Ns 0
Ka 0.000000 0.000000 0.000000
Kd 0.8 0.8 0.8
Ks 0.8 0.8 0.8
d 1
illum 2
# Added just for testing:
newmtl Demo
Ns 1
Ks 0.9 0.9 0.9
d 42
illum 7
Выход читает
phrase_parse -> true
remaining input: ''
void dump(const T&) [with T = std::vector<blender::mtl::material>]
-----
material {
Ns:0
Ka:{r:0,g:0,b:0}
Kd:{r:0.8,g:0.8,b:0.8}
Ks:{r:0.8,g:0.8,b:0.8}
d:1
illum:2(Highlight on)
}
material {
Ns:1
Ka:(unspecified)
Kd:(unspecified)
Ks:{r:0.9,g:0.9,b:0.9}
d:42
illum:7(Transparency: Refraction on/Reflection: Fresnel on and Ray trace on)
}
-----
Вот список
#define BOOST_SPIRIT_USE_PHOENIX_V3
#define BOOST_SPIRIT_DEBUG
#include <boost/fusion/adapted.hpp>
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/karma.hpp> // for debug output/streaming
#include <boost/spirit/include/phoenix.hpp>
#include <boost/spirit/include/phoenix_operator.hpp>
namespace qi = boost::spirit::qi;
namespace phx= boost::phoenix;
namespace wavefront { namespace obj
{
} }
namespace blender { namespace mtl // material?
{
struct Ns { int exponent; }; // specular exponent
struct Reflectivity { double r, g, b; };
using Name = std::string;
using Ka = Reflectivity;
using Kd = Reflectivity;
using Ks = Reflectivity;
using dissolve_factor = double;
enum class illumination_model {
color, // 0 Color on and Ambient off
color_ambient, // 1 Color on and Ambient on
highlight, // 2 Highlight on
reflection_ray, // 3 Reflection on and Ray trace on
glass_ray, // 4 Transparency: Glass on
// Reflection: Ray trace on
fresnel_ray, // 5 Reflection: Fresnel on and Ray trace on
refract_ray, // 6 Transparency: Refraction on
// Reflection: Fresnel off and Ray trace on
refract_ray_fresnel,// 7 Transparency: Refraction on
// Reflection: Fresnel on and Ray trace on
reflection, // 8 Reflection on and Ray trace off
glass, // 9 Transparency: Glass on
// Reflection: Ray trace off
shadow_invis, // 10 Casts shadows onto invisible surfaces
};
struct material
{
Name _Name;
boost::optional<Ns> _Ns;
boost::optional<Reflectivity> _Ka;
boost::optional<Reflectivity> _Kd;
boost::optional<Reflectivity> _Ks;
boost::optional<dissolve_factor> _d;
boost::optional<illumination_model> _illum;
};
using mtl_file = std::vector<material>;
///////////////////////////////////////////////////////////////////////
// Debug output helpers
std::ostream& operator<<(std::ostream& os, blender::mtl::illumination_model o)
{
using blender::mtl::illumination_model;
switch(o)
{
case illumination_model::color: return os << "0(Color on and Ambient off)";
case illumination_model::color_ambient: return os << "1(Color on and Ambient on)";
case illumination_model::highlight: return os << "2(Highlight on)";
case illumination_model::reflection_ray: return os << "3(Reflection on and Ray trace on)";
case illumination_model::glass_ray: return os << "4(Transparency: Glass on/Reflection: Ray trace on)";
case illumination_model::fresnel_ray: return os << "5(Reflection: Fresnel on and Ray trace on)";
case illumination_model::refract_ray: return os << "6(Transparency: Refraction on/Reflection: Fresnel off and Ray trace on)";
case illumination_model::refract_ray_fresnel: return os << "7(Transparency: Refraction on/Reflection: Fresnel on and Ray trace on)";
case illumination_model::reflection: return os << "8(Reflection on and Ray trace off)";
case illumination_model::glass: return os << "9(Transparency: Glass on/Reflection: Ray trace off)";
case illumination_model::shadow_invis: return os << "10(Casts shadows onto invisible surfaces)";
default: return os << "ILLEGAL VALUE";
}
}
std::ostream& operator<<(std::ostream& os, blender::mtl::Reflectivity const& o)
{
return os << "{r:" << o.r << ",g:" << o.g << ",b:" << o.b << "}";
}
std::ostream& operator<<(std::ostream& os, blender::mtl::material const& o)
{
using namespace boost::spirit::karma;
return os << format("material {"
"\n\tNs:" << (auto_ | "(unspecified)")
<< "\n\tKa:" << (stream | "(unspecified)")
<< "\n\tKd:" << (stream | "(unspecified)")
<< "\n\tKs:" << (stream | "(unspecified)")
<< "\n\td:" << (stream | "(unspecified)")
<< "\n\tillum:" << (stream | "(unspecified)")
<< "\n}", o);
}
} }
BOOST_FUSION_ADAPT_STRUCT(blender::mtl::Reflectivity,(double, r)(double, g)(double, b))
BOOST_FUSION_ADAPT_STRUCT(blender::mtl::Ns, (int, exponent))
BOOST_FUSION_ADAPT_STRUCT(blender::mtl::material,
(boost::optional<blender::mtl::Ns>, _Ns)
(boost::optional<blender::mtl::Ka>, _Ka)
(boost::optional<blender::mtl::Kd>, _Kd)
(boost::optional<blender::mtl::Ks>, _Ks)
(boost::optional<blender::mtl::dissolve_factor>, _d)
(boost::optional<blender::mtl::illumination_model>, _illum))
namespace blender { namespace mtl { namespace parsing
{
template <typename It>
struct grammar : qi::grammar<It, qi::blank_type, mtl_file()>
{
template <typename T=qi::unused_type> using rule = qi::rule<It, qi::blank_type, T>;
rule<Name()> _Name;
rule<Ns()> _Ns;
rule<Reflectivity()> _Ka;
rule<Reflectivity()> _Kd;
rule<Reflectivity()> _Ks;
rule<dissolve_factor()> _d;
rule<illumination_model()> _illum;
rule<mtl_file()> start;
rule<material()> _material;
rule<void(material&)> statement;
rule<> comment;
grammar() : grammar::base_type(start)
{
using namespace qi;
using phx::bind;
using blender::mtl::material;
_Name = "newmtl" >> lexeme [ +graph ];
_Ns = "Ns" >> double_;
_Ka = "Ka" >> double_ >> double_ >> double_;
_Kd = "Kd" >> double_ >> double_ >> double_;
_Ks = "Ks" >> double_ >> double_ >> double_;
_d = "d" >> double_;
_illum %= "illum" >> qi::int_ [ _pass = (_1>=0) && (_1<=10) ];
comment = '#' >> *(char_ - eol);
statement=
comment
| _Ns [ bind(&material::_Ns, _r1) = _1 ]
| _Ka [ bind(&material::_Ka, _r1) = _1 ]
| _Kd [ bind(&material::_Kd, _r1) = _1 ]
| _Ks [ bind(&material::_Ks, _r1) = _1 ]
| _d [ bind(&material::_d, _r1) = _1 ]
| _illum [ bind(&material::_illum, _r1) = _1 ]
;
_material = -comment % eol
>> _Name [ bind(&material::_Name, _val) = _1 ] >> eol
>> -statement(_val) % eol;
start = _material % -eol;
BOOST_SPIRIT_DEBUG_NODES(
(start)
(statement)
(_material)
(_Name) (_Ns) (_Ka) (_Kd) (_Ks) (_d) (_illum)
(comment))
}
};
} } }
#include <fstream>
template <typename T>
void dump(T const& data)
{
using namespace boost::spirit::karma;
std::cout << __PRETTY_FUNCTION__
<< "\n-----\n"
<< format(stream % eol, data)
<< "\n-----\n";
}
void testMtl(const char* const fname)
{
std::ifstream mtl(fname, std::ios::binary);
mtl.unsetf(std::ios::skipws);
boost::spirit::istream_iterator f(mtl), l;
using namespace blender::mtl::parsing;
static const grammar<decltype(f)> p;
blender::mtl::mtl_file data;
bool ok = qi::phrase_parse(f, l, p, qi::blank, data);
std::cout << "phrase_parse -> " << std::boolalpha << ok << "\n";
std::cout << "remaining input: '" << std::string(f,l) << "'\n";
dump(data);
}
int main()
{
testMtl("untitled.mtl");
}
Ваш файл похож на 'ini' файл? – P0W
@ P0W нет, и у меня есть разные типы файлов с различным синтаксисом/семантикой – user2485710
Если у вас есть простой пример ввода, я могу бросить вам образец духа – sehe