in the case of the learn opengl model.h how would you then pass the per mesh colours?

Do you mean this?:

- https://github.com/JoeyDeVries/LearnOpenGL/blob/master/includes/learnopengl/model.h
- https://github.com/JoeyDeVries/LearnOpenGL/blob/master/includes/learnopengl/mesh.h

At first glance, a `Vertex`

doesn’t currently contain a color:

```
struct Vertex {
// position
glm::vec3 Position;
// normal
glm::vec3 Normal;
// texCoords
glm::vec2 TexCoords;
// tangent
glm::vec3 Tangent;
// bitangent
glm::vec3 Bitangent;
};
```

So you’d probably need to add that (if you needed the color value to vary per vertex).

If you didn’t need it to vary per-vertex however, you could use a constant vertex attribute value.