As an exercise set to myself, I wanted to make a Mesh loader using modern OpenGL.

However, I have to ways of representing the notion of face of a mesh.

Currently, I am using what seems the most natural. A mesh contains a


and a Triangle is simply

struct Triangle
    unsigned int Vertices[3];

(i.e. each triangle stores the three indices of its vertices). NOTE : a mesh contains others things (such as the vertices and the normals but I didn't include them here for simplicity).

However, OpenGL require a different representation for using EBO : only one static array on indices (implicitly grouped by 3).

What I have come up with is a trade-off between these representations : once the mesh is loaded, I generate a static array of size

3 * mesh->Faces.size()

but I assume this is not the best option for memory use and redundancy.

So my questions are :

  • If I want to keep my current representation of a mesh (with a vector of faces), how should I set OpenGL to properly render such a mesh ? Is my current solution of generating a new static a good practice ?
  • Assuming I can use the representation I want for my mesh. What would you recommand and why ?

Actually your current way is fine.

C++ struct layout will let you turn the Triangle* into a int* and store that into the EBO.

| improve this answer | |
  • \$\begingroup\$ Thanks ! And how should I turn properly turn the std::vector<Triangle> to my unsigned int* that OpenGL require ? \$\endgroup\$ – Rivten Mar 29 '16 at 15:20
  • \$\begingroup\$ vector has a data() function that'll return the Triangle* which you can cast to the int*. \$\endgroup\$ – ratchet freak Mar 29 '16 at 15:23

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.