I managed to solved a lid-driven cavity flow using LB code. It gave me the velocity field data points.

Now I have to obtain streamlines too, of course from the obtained velocity field.

Besides, I know the theory of Potential Flow as well as all of the associated relations.

How can I directly draw the streamlines of this flow without solving a Poisson equation. If numerical integration must to be used (as I guess), How should I do handle with partial derivatives?