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local EPSILON = 0.0001
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local function isNearZero(f)
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return math.abs(f) < EPSILON
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end
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Vector3D = function(x, y, z)
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local mt = {}
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local obj = {
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x = x,
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y = y,
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z = z
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}
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function obj:get()
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return self.x, self.y, self.z
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end
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function obj:length()
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return math.sqrt(self.x * self.x + self.y * self.y + self.z * self.z)
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end
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function obj:normalize()
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local len = self:length()
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if len < EPSILON then return 0 end
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self.x = self.x / len
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self.y = self.y / len
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self.z = self.z / len
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return len
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end
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function obj:zeroNearZero()
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if isNearZero(self.x) then self.x = 0 end
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if isNearZero(self.y) then self.y = 0 end
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if isNearZero(self.z) then self.z = 0 end
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end
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function obj:dotProduct(v)
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return self.x * v.x + self.y * v.y + self.z * v.z
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end
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function obj:crossProduct(v)
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local x, y, z = self.x, self.y, self.z
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self.x = y * v.z - v.y * z
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self.y = z * v.x - v.z * x
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self.z = x * v.y - v.x * y
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end
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obj.zero_near_zero = obj.zeroNearZero
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obj.dot_product = obj.dotProduct
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obj.cross_product = obj.crossProduct
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function mt:__add(v)
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return Vector3D(self.x + v.x, self.y + v.y, self.z + v.z)
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end
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function mt:__mul(v)
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if type(v) == "number" then
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return Vector3D(self.x * v, self.y * v, self.z * v)
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end
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return Vector3D(self.x * v.x, self.y * v.y, self.z * v.z)
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end
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function mt:__sub(v)
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return Vector3D(self.x - v.x, self.y - v.y, self.z - v.z)
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end
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setmetatable(obj, mt)
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return obj
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end
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return Vector3D
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