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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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