Loop Network (desire-routed)

The Loop Network, with each candidate loop routed along the lanes people would walk. Before any road is placed, every home's best walking route — to the street, and to every other home — is traced through the gaps between buildings, with routes that pay for turning and keep their distance from walls. Where many routes run, beyond what the same block with its buildings removed would send there, the ground is a desire line.

The routing grid is then made cheaper along those lines, so the two paths of every candidate loop bend toward them. What gets built is still the Loop Network's choice — each loop is scored by permeability gain per home displaced — only the shape of the candidates follows the lanes. The pull is deliberately gentle: a stronger one drags roads off the best loops.

Configuration: conf/method/cycle_native_betweenness_contrast.yaml

Head-to-head on one deep block

From the method-comparison example: six reblockers on ZAF.9.3.1_1_40972, the deepest topology-tractable block in the Cape Town metro (263 parcels, up to 7 rings deep), graded on permeability (a flow measure of how easily every parcel can reach a street) against displacement.

At this method's full build-out on that block (terminal point of its permeability-vs-displacement frontier):

homes displaced	permeability
20.0%	96.4%

On the settlement-scale benchmark

From the Cape Town benchmark — the single-block, 6,619-parcel multiblock_depth_density region.

Roads added busiest-first, each preceded by whatever it needs to reach the street, so every frame is a network you could actually build. The animation stops where the network first reaches the matched-permeability standard — every method's GIF ends at the same benefit, so what differs is the disruption spent getting there. The deep interior drains as the network reaches in:

The same region under the two lenses — truncated to the shared displacement budget (left) and run until it reaches the shared permeability standard (right), coloured by access depth:

matched displacement	matched permeability

Matched displacement: at 14,663 m of road it reaches permeability 92.6%, displacing 10.0% of homes.

Matched permeability: reaches the permeability target with 1,762 m of road, displacing 0.7% of homes.