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RedMew/map_gen/shape/spiral.lua
2018-10-02 21:58:22 +02:00

17 lines
403 B
Lua

local thickness = 72 -- change this to change the spiral thickness.
local inv_pi = 1 / math.pi
local thickness2 = thickness * 2
return function(x, y)
local d_sq = x * x + y * y
if d_sq < 16384 then --d < 128
return true
end
local angle = 1 + inv_pi * math.atan2(x, y)
local offset = d + (angle * thickness)
return offset % thickness2 >= thickness
end