+ glm::dvec3 to_tile = p.TileCenter(surface, x, y);
+ double near_axis = std::abs(glm::dot(glm::normalize(to_tile), axis));
+ if (near_axis > cap_thresh) {
+ p.TileAt(surface, x, y).type = ice;
+ continue;
+ }
+ float elevation = rand::OctaveNoise(
+ elevation_gen,
+ to_tile / p.Radius(),
+ 3, // octaves
+ 0.5, // persistence
+ 2 / p.Radius(), // frequency
+ 2, // amplitude
+ 2 // growth
+ );
+ if (elevation < water_thresh) {
+ p.TileAt(surface, x, y).type = water;
+ } else if (elevation < beach_thresh) {
+ p.TileAt(surface, x, y).type = sand;
+ } else if (elevation < mountain_thresh) {
+ p.TileAt(surface, x, y).type = grass;
+ } else {
+ p.TileAt(surface, x, y).type = rock;
+ }