main.cpp

#include <boost/hana.hpp>
#include <iostream>

template <typename T>
struct basic_type {
    using type = T;
};

namespace hana = boost::hana;
using namespace hana::literals;

int main() {
    auto position = hana::make_pair(hana::type_c<float>, 3);
    auto normal = hana::make_pair(hana::type_c<float>, 3);
    auto texCoord = hana::make_pair(hana::type_c<float>, 2);

    auto layout = hana::make_tuple(position, normal, texCoord);

    int byteSize = 0;
    hana::for_each(layout, [&](auto component) {
        using T = typename decltype(+hana::first(component))::basic_type::type;
        byteSize += (sizeof(T) * hana::second(component));
    });

    int count = 0;
    int offset = 0;
    hana::for_each(layout, [&](auto component) {
        using T = typename decltype(+hana::first(component))::basic_type::type;

        std::cout << "----\n";
        std::cout << "Index: " << count << "\n";
        std::cout << "Size: " << hana::second(component) << "\n";
        std::cout << "Stride: " << byteSize << "\n";
        std::cout << "Offset: " << offset << "\n";

        count++;
        offset += (sizeof(T) * hana::second(component));
    });
}