Abstract
Transfer-matrix results in 2D show that wetting of a rough, self-affine wall induced by bulk bond disorder turns discontinuous as soon as the wall roughness exponent ζW exceeds ζ0 = 2/3, the spatial anisotropy index of interface fluctuations in the bulk. For ζW < 2/3 critical wetting is recovered, in the same universality class as for the flat-wall case. These and related findings suggest a free-energy structure such to imply first-order wetting also without disorder, or in 3D, whenever ζW exceeds the appropriate ζ0. The same thresholds should apply also with van der Waals forces, in cases when ζ0 implies a strong-fluctuation regime.