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Vec2 = {}
Vec2.__index = Vec2
Vec2.__add = function(a, b) return vec2(a.x + b.x, a.y + b.y) end
Vec2.__unm = function(a) return vec2(-a.x, -a.y) end
Vec2.__sub = function(a, b) return a + (-b) end
Vec2.__mul = function(a, b)
if (type(b) == "number") then return vec2(a.x * b, a.y * b) end -- scalar mult
return a.x * b.x + a.y * b.y
end
Vec2.__div = function(a, b) return vec2(a.x / b.x, a.y / b.y) end
Vec2.__tostring = function(a) return "(" .. fmt(a.x) .. "," .. fmt(a.y) .. ")" end
function Vec2:magnitude()
return sqrt(self.x * self.x + self.y * self.y)
end
function Vec2:normal()
local m = self:magnitude()
if m == 0 then return vec2(self.x, self.y) end
return vec2(self.x / m, self.y / m)
end
function Vec2:apply(f)
return vec2(f(self.x), f(self.y))
end
function vec2(x, y)
if type(x) == "table" then return vec2(x.x, x.y) end
return setmetatable({ x = x, y = y }, Vec2)
end
function normalize_scalar(x)
if x == 0 then return 0 end
if x < 0 then return -1 end
return 1
end
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