I need to calculate the tangent and bitangent for my models and i have found an algorithm to do it but i havent been able to fully understand on what to apply the algorithm. in some places it says to do it for each face others to go through all the verts of the model and do it.
so which is the right way? do it for the 3 verts of each face? and if that is the case what happens when one vert is in more than one face?