Courier in Megapolis: Dijkstra Route Planning Through City Traffic (2D)

City & Traffic

Grid size 6 × 6

Traffic volatility 55%

Sim speed 1.0×

Routing

Live Readout

Elapsed time

0.0 s

Deliveries

Distance traveled

0.0 blk

Avg. speed

0.00 blk/s

Route efficiency

1.00×

Network congestion

How it works

The city is a rectangular grid graph — intersections as nodes, streets as edges, each 1 block long. Every street's congestion oscillates over time from two overlaid sine waves scaled by the volatility slider, standing in for rush-hour and local surges:

congestion(edge, t) = base + V·0.5·wave1(t) + V·0.15·wave2(t)
travel time(edge)   = 1 block / (speed · (1 − congestion · 0.8))

Before each delivery leg the courier runs Dijkstra's shortest-path algorithm over the whole grid using current travel-time weights — not straight-line distance — so the route accounts for which streets are jammed right now. With adaptive routing on, the route is recomputed from the courier's current position every time it reaches an intersection, reacting to newly-formed jams; with it off, the route computed at delivery pickup is kept even if congestion later shifts elsewhere, so you can watch efficiency drop by comparison.

Route efficiency — cumulative blocks actually traveled ÷ cumulative straight-line (Euclidean) distance to each target; a grid path is never shorter than the diagonal, so lower is better.
Network congestion — the current average congestion value across every street in the city.

Free-flowing street Congested street Courier