A parameter stream specifies numerical, Boolean, and other parameters that typically vary quickly over time — the positions, rotations, and states that change as a realm’s game loop runs. It is the fast-moving counterpart to the structural stream, and together the two carry the Scene Composition Protocol.
Higher-order derivatives#
A parameter may carry derivatives alongside its value: a point’s position can also specify velocity and acceleration. This is what lets a node extrapolate between updates instead of waiting for them — it renders the predicted value each frame and corrects when the next record arrives. Motion then stays smooth at frame rate while the stream runs at whatever rate the network and the loop sustain, and an update becomes a correction rather than a hard requirement.
That property matters more here than in a client/server game. Records reach a node through peers that may leave mid-stream, so gaps are ordinary; a representation that degrades into prediction rather than into a stall is the difference between a realm that stutters under churn and one that does not.
This is the bargain networked simulation has always made under the name dead reckoning: tolerance of latency and loss, paid for with visible correction when a prediction was wrong. How corrections are blended, and how much divergence is tolerated before a snap, is not yet specified.
External links#
Similar concepts and prior art:
- Dead reckoning on Wikipedia — including its use in networked simulation
- Distributed Interactive Simulation — the standard that made dead reckoning normative
- Snapshot Interpolation — Gaffer on Games
- Netcode and delta encoding on Wikipedia