func EachChunkNearby(wc coords.World, cb func(cc coords.Chunk, priority int)) {
occ := func(cc coords.Chunk, x, y, z int) coords.Chunk {
return coords.Chunk{
X: cc.X + x,
Y: cc.Y + y,
Z: cc.Z + z,
}
}
eachWithin := func(cc coords.Chunk, xdist, ydist, zdist int, cb func(newCC coords.Chunk, dist int)) {
abs := func(n int) int {
if n < 0 {
return -n
}
return n
}
dist := func(x, y, z int) int {
return abs(x) + abs(y) + abs(z)
}
cb(cc, 0)
for x := -xdist; x <= xdist; x++ {
for y := -ydist; y <= ydist; y++ {
for z := -zdist; z <= zdist; z++ {
cb(occ(cc, x, y, z), dist(x, y, z))
}
}
}
}
cc := wc.Chunk()
eachWithin(cc, 2, 1, 2, func(newCC coords.Chunk, dist int) {
// We want to prioritize further away chunks lower, but the
// priority must be a positive integer.
cb(newCC, 10-dist)
})
oc := wc.Offset()
if oc.Y <= 4 {
cb(occ(cc, 0, -1, 0), 1)
} else if oc.Y >= 28 {
cb(occ(cc, 0, 1, 0), 1)
}
}
