Model

Define a model

Overview

Last time we created a mesh, now we’ll wrap our mesh class up in a model class.

A model for us will contain information about the entity the mesh represents. Properties such as color, reflectivity, etc are examples of things we could store in a model. However for the time being we’re going to put all those aside and just store the model matrix. The model matrix handles transforming an entity from the local coordinate sytem where its vertex positions are defined into the world coordinate system that is shared by all entities in the scene. If you need a refresher check out this tutorial

#include <mesh.h>
#include <Eigen/Core>
#include <vector3G.h>

#ifndef MODEL
#define MODEL
/**
    \brief Defines a model used for rendering

    Model is the base class for all entities that are rendered in a scene. It stores properites such as the mesh, material properties, textures, etc. It also holds the <b>model matrix</b> which handles transforming the mesh from local coordinates to world coordinates. See [Here](https://learnopengl.com/#!Getting-started/Coordinate-Systems) for more details.
**/
class Model {
   public:
        /**
            @return The model matrix
        **/
        Eigen::Matrix<GLfloat,4,4> GetModelMatrix();
       
        /**
            Sets the model matrix
            @param model Matrix to be set as the model matrix
        **/ 
        void SetModelMatrix(Eigen::Matrix<GLfloat,4,4> model);

        /**
            @return Copy of the mesh used by this model
        **/
        Mesh GetMesh();
        
     protected:
        /**
            The mesh for this model
        **/
        Mesh m_mesh; 
        /**
            The model matrix. This handles transforming from local model coordinates to world coordinates
        **/
        Eigen::Matrix<GLfloat,4,4> m_model_matrix;  
        
        /**
            Builds a Model with an empty mesh and identity model matrix
        **/
        Model();
    
};
#endif

#include <model.h>

Model::Model()
{
    m_model_matrix.setIdentity();
}

Eigen::Matrix<GLfloat, 4, 4> Model::GetModelMatrix()
{
    return m_model_matrix;
};

void Model::SetModelMatrix(Eigen::Matrix<GLfloat,4,4> m)
{
    m_model_matrix = m;
};

Mesh Model::GetMesh()
{
    return m_mesh;
}