Embodiments include storing values of a first plurality of nodes in memory based on tracking the position of a plurality of points of a physical object and maintaining a second plurality of nodes in memory, each node of the second plurality of nodes corresponding to a node of the first plurality. The values of the second plurality of nodes can be used to model interactions with other objects and to render a view of a simulated object. The simulation can access data identifying a simulation boundary and selectively update values of the second plurality of nodes using the first plurality of nodes while ensuring that the simulation boundary is not violated. A value of the second plurality of nodes can be set to be different from the value of the corresponding one of the first plurality of nodes if using the first node's value would violate the boundary.