Mesh.cpp

#include "Mesh.hpp"

Mesh::Mesh(vector<Vertex> vertices, vector<unsigned int> indices, vector<Texture> textures)
{
    this->vertices = vertices;
    this->indices = indices;
    this->textures = textures;

    // now that we have all the required data, set the vertex buffers and its attribute pointers.
    setupMesh();
}

void Mesh::Draw(Shader& shader)
{
    // bind appropriate textures
    unsigned int diffuseNr = 1;
    unsigned int specularNr = 1;
    unsigned int normalNr = 1;
    unsigned int heightNr = 1;
    for (unsigned int i = 0; i < textures.size(); i++)
    {
        glActiveTexture(GL_TEXTURE0 + i); // active proper texture unit before binding
        // retrieve texture number (the N in diffuse_textureN)
        string number;
        string name = textures[i].type;
        if (name == "texture_diffuse")
            number = std::to_string(diffuseNr++);
        else if (name == "texture_specular")
            number = std::to_string(specularNr++); // transfer unsigned int to string
        else if (name == "texture_normal")
            number = std::to_string(normalNr++); // transfer unsigned int to string
        else if (name == "texture_height")
            number = std::to_string(heightNr++); // transfer unsigned int to string

        // now set the sampler to the correct texture unit
        glUniform1i(glGetUniformLocation(shader.ID, (name + number).c_str()), i);
        // and finally bind the texture
        glBindTexture(GL_TEXTURE_2D, textures[i].id);
    }

    // draw mesh
    glBindVertexArray(VAO);
    glDrawElements(GL_TRIANGLES, static_cast<unsigned int>(indices.size()), GL_UNSIGNED_INT, 0);
    glBindVertexArray(0);

    // always good practice to set everything back to defaults once configured.
    glActiveTexture(GL_TEXTURE0);
}