StepWise
100+ data structures and algorithms, every step narrated with its pseudocode line and variables; step back, share as a link, embed in Canvas.
Apps / Lockstep Lab
Lockstep Lab
Watch deterministic lockstep and rollback netcode work, and fail.
What it does
A teaching lab for how online multiplayer games stay in sync. Run two to four simulated players of a small strategy game over a fake network with adjustable delay, jitter and lost packets, and compare the two classic approaches: wait for everyone's input each turn (lockstep) or predict and rewind when wrong (rollback). Switch on common causes of drift, such as floating-point math or unseeded random numbers, and it pinpoints the first unit and value where players disagree. Five auto-graded exercises test students' own simulation code.
Good to know
The differences between computers are simulated and exaggerated, so drift shows up far sooner than on real hardware.
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