Oh thanks a lot Yann L! My engine's approach to texturing is quite different from clipmaps or megatexture techniques, so I will rather relay on Opengl when it comes to texture managment. On the other hand, I would really want to have full control of this aspect (for texturing very large scale terrains) as I just load only the textures visible to the camera and delete all the others. As the whole project is academic (and maybe ready for a paper), I can't say more concerning those techniques. Thanks again everyone!