#road generation

[timetocode]

Slight variant on the coastal highway generator, this one attempts to remove some of the V shapes from the original (the Vs are in the second image). The algo basically replaces these V shaped detours with an intersection which can be used to visit the original target of the V, or continue onwards along the periphery of the island. It has some artifacts that still need worked out.

When this works a little better I’ll have to make an algo that adds residential and commercial lots..and more roads. Then v1 map generator will be good enough to go back to doing art for awhile.

[procedural-generation]

You'd think that putting a road down would just be a matter of pathfinding, but a good road often needs to alter the terrain a bit. The road needs to be flat enough to drive on, sloped enough to handle the terrain, with bridges, tunnels, and excavation to carve into the sides of hills. Not to mention that the road shouldn't be too sharply curved.

Here’s a paper from 2010 by Eric Galin, Adrien Peytavie, Nicolas Maréchal, and Eric Guérin talking about how they generated roads. They calculate a discrete shortest path, using segment path masks to takes care of the difference between discrete segments and a continuous path, plus a bunch of cost functions and calculations to hand curves and bridges.

Once they had a path, they used it to generate clothoid splines. Some bits were further segmented to mark bridges and tunnels, and then the roads themselves were blended with the terrain by removing the vegetation along the route, refining the mesh, and adapting it in the blend regions next to the road.

http://arches.liris.cnrs.fr/publications/EG2010.html