  OR-constrained (ORC) graphical user interface layouts unify conventional
constraint-based layouts with flow layouts, which enables the definition of
flexible layouts that adapt to screens with different sizes, orientations, or
aspect ratios with only a single layout specification. Unfortunately, solving
ORC layouts with current solvers is time-consuming and the needed time
increases exponentially with the number of widgets and constraints. To address
this challenge, we propose ORCSolver, a novel solving technique for adaptive
ORC layouts, based on a branch-and-bound approach with heuristic preprocessing.
We demonstrate that ORCSolver simplifies ORC specifications at runtime and our
approach can solve ORC layout specifications efficiently at near-interactive
rates.
