ObjReader.hpp

/*
 * ObjReader.hpp
 *
 *  Created on: Oct 31, 2018
 *      Author: i-bird
 */
 
#ifndef OBJREADER_HPP_
#define OBJREADER_HPP_
 
#include "config.h"
#include "Space/Shape/Point.hpp"
 
#ifdef HAVE_TINYOBJLOADER
#include "tiny_obj_loader.h"
 
template<typename T>
class ObjReader
{
    size_t shape_counter;
    size_t face_counter;
    size_t index_offset;
 
    tinyobj::attrib_t attrib;
    std::vector<tinyobj::shape_t> shapes;
    std::vector<tinyobj::material_t> materials;
 
    size_t end_shape;
 
    public:
 
    ObjReader()
    {}
 
    bool read(std::string file)
    {
        shape_counter = 0;
        face_counter = 0;
        index_offset = 0;
 
        shapes.clear();
        materials.clear();
 
        std::string err;
        bool ret = tinyobj::LoadObj(&attrib, &shapes, &materials, &err, file.c_str());
 
        if (!err.empty())
        {std::cerr << err << std::endl;}
 
        if (!ret)
        {return false;}
 
        end_shape = shapes.size();
 
        return true;
    }
 
 
    ObjReader & operator++()
    {
        index_offset += getFaceNVertex();
        ++face_counter;
 
        if (face_counter >= shapes[shape_counter].mesh.num_face_vertices.size())
        {
            face_counter = 0;
            index_offset = 0;
            ++shape_counter;
        }
 
        return *this;
    }
 
    inline bool isNext()
    {
        return shape_counter < end_shape;
    }
 
    inline void setObject(int i)
    {
        if (i >= shapes.size())
        {
            std::cerr << "Error " << __FILE__ << ":" << __LINE__ << " you selected object " << i << " but the file contain " << shapes.size() << " objects" << std::endl;
        }
 
        shape_counter = i;
        end_shape = i+1;
    }
 
 
    unsigned int getFaceNVertex()
    {
        return  shapes[shape_counter].mesh.num_face_vertices[face_counter];
    }
 
    inline Point<3,T> getVertex(unsigned int v)
    {
        Point<3,T> p;
 
        tinyobj::index_t idx = shapes[shape_counter].mesh.indices[index_offset + v];
 
        p.get(0) = attrib.vertices[3*idx.vertex_index+0];
        p.get(1) = attrib.vertices[3*idx.vertex_index+1];
        p.get(2) = attrib.vertices[3*idx.vertex_index+2];
 
        return p;
    }
 
    inline Point<3,T> getNormal(unsigned int v)
    {
        Point<3,T> p;
 
        tinyobj::index_t idx = shapes[shape_counter].mesh.indices[index_offset + v];
 
        p.get(0) = attrib.normals[3*idx.normal_index+0];
        p.get(1) = attrib.normals[3*idx.normal_index+1];
        p.get(2) = attrib.normals[3*idx.normal_index+2];
 
        return p;
    }
 
    inline Point<2,T> getTexCoord(unsigned int v)
    {
        Point<2,T> p;
 
        tinyobj::index_t idx = shapes[shape_counter].mesh.indices[index_offset + v];
 
        p.get(0) = attrib.texcoords[2*idx.texcoord_index+0];
        p.get(1) = attrib.texcoords[2*idx.texcoord_index+1];
 
        return p;
    }
};
 
#endif
 
#endif /* OBJREADER_HPP_ */