  Smectic materials represent a unique state between fluids and solids,
characterized by orientational and partial positional order, making them
notoriously difficult to model, particularly in confining geometries. We
propose a complex order parameter tensor to describe the local degree of
lamellar ordering, layer displacement and orientation. The theory accounts for
both dislocations and disclinations, as well as arrested configurations and
colloid-induced local ordering. It considerably simplifies numerics,
facilitating studies on the dynamics of topologically complex lamellar systems.
