tuned pipeline to 60 fps

src/orisys/hhd/solvers/masked_sparse.py

@@ -19,3 +19,18 @@ class MaskedSparseSolver:
 
         sol_active = domain.factor(rhs)  # (N,) reduced-system potential
         return domain.scatter(sol_active, f)
+
+    def solve_pair(self, f0, f1, domain: MaskedDomain):
+        """Solve two masked Poisson RHS with one reused sparse factorization call."""
+        rhs_pair = domain.prepare_rhs_pair(f0, f1)
+        if rhs_pair.shape[0] == 0:
+            empty = numpy.zeros_like(f0, dtype=numpy.float32)
+            return empty, empty.copy()
+
+        try:
+            sol_pair = domain.factor(rhs_pair)  # (N, 2) reduced-system potentials
+        except Exception:
+            sol_pair = numpy.column_stack(
+                [domain.factor(rhs_pair[:, 0]), domain.factor(rhs_pair[:, 1])]
+            )
+        return domain.scatter_pair(sol_pair, f0)