  Topological filters via sheaves generalize the classical linear
translation-invariant filter theory by attaching the filter computation locally
to a simplicial topological space. This paper develops topological filters for
causal signal flow over a 2-simplex. Our construction retains the established
construction for 1-simplices and we show how an apparent conflict in the sheaf
assignment can be resolved by a concurrent extension, which introduces an
auxiliary 1-simplex that computes the resolution. Furthermore, we discuss how
singularities formed by double cone connections can be resolved.
