Model.h

#pragma once
#include <vector>
#include <string>
#include "Mesh.h"
#include <assimp/Importer.hpp>
#include <assimp/scene.h>
#include <assimp/postprocess.h>

class Model
{
public:
    /*  Model Data */
    std::vector<Texture> textures_loaded;	// stores all the textures loaded so far, optimization to make sure textures aren't loaded more than once.
    std::vector<Mesh> meshes;
    std::string directory;
    bool gammaCorrection;

    /*  Functions   */
    // constructor, expects a filepath to a 3D model.
    Model(std::string const& path, bool gamma = false) : gammaCorrection(gamma)
    {
        loadModel(path);
    }

    // draws the model, and thus all its meshes
    void Draw(Shader shader);

private:
    /*  Functions   */
    // loads a model with supported ASSIMP extensions from file and stores the resulting meshes in the meshes vector.
    void loadModel(std::string const& path);

    // processes a node in a recursive fashion. Processes each individual mesh located at the node and repeats this process on its children nodes (if any).
    void processNode(aiNode* node, const aiScene* scene);

    Mesh processMesh(aiMesh* mesh, const aiScene* scene);

    // checks all material textures of a given type and loads the textures if they're not loaded yet.
    // the required info is returned as a Texture struct.
    std::vector<Texture> loadMaterialTextures(aiMaterial* mat, aiTextureType type, std::string typeName);
};