A simplification architecture for exploring navigation tradeoffs in mobile VR

Interactive applications on mobile devices often reduce data fidelity to adapt to resource constraints and variable user preferences. In virtual reality applications, the problem of reducing scene graph fidelity can be stated as a combinatorial optimization problem, where a part of the scene graph with maximum fidelity is chosen such that the resources it requires are below a given threshold and the hierarchical relationships are maintained. The problem can be formulated as a variation of the tree knapsack problem, which is known to be NP-hard. For this reason, solutions to this problem result in a tradeoff that affects user navigation. On one hand, exact solutions provide the highest fidelity but may take long time to compute. On the other hand, greedy solutions are fast but lack high fidelity. We present a simplification architecture that allows the exploration of such navigation tradeoffs. This is achieved by a formulating the problem in a generic way and developing software components that allow the dynamic selection of algorithms and constraints. The experimental results show that the architecture is flexible and supports dynamic reconfiguration.