In the game, transportation of goods is handled by little drones you can build/purchase at factories located across the map. You don't control these directly, so it'll require some pathfinding to get them around.
Because the map is too large to cover with a (dense enough) regular grid, I generate a Poisson field with points packed with a minimal distance based on how close they lie to the underlying scene geometry, with points more densely distributed near the terrain surface.
Next, the 1D ordering of sample points gets optimized by sorting them along a Hilbert-like curve, like this:
This for two reasons: it improves tree construction times, as nearby points are likely to result in similar graphs when passed through an A* search (while reusing the ordering of points from previous searches). Secondly, if points end up with comparable ordering in whatever lookup table they're referred to in, then these tables can easily be compressed RLE-style. This allows me to store and traverse all n[sup]2[/sup] flow fields describing the fastest route from every point to every other point in the graph.
Here I've set the drones to follow the second camera through the flow field: