Least-Cost Tree

A greedy least-cost-path reblocker with one physical knob, repulsion. Each road is the least-cost path from the current deepest parcel to the existing road+street network on a grid whose edge costs repel from building points — the knob sweeps from aspirational straight roads to buildable roads that hug the maximum-clearance (Voronoi) gaps between homes. Roads are added until an access-depth target is met, so it spends the least road for the depth it buys.

Configuration: conf/method/clearance.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
27.7%	94.8%