59 lines
No EOL
1.2 KiB
Lua
59 lines
No EOL
1.2 KiB
Lua
local math = math
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local mathFloor = math.floor
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local mathRandom = math.random
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XMath = XMath or {}
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function XMath.RandByWeights(weights)
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local weightSum = 0
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for i = 1, #weights do
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weightSum = weightSum + weights[i]
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end
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local rand = mathRandom(weightSum)
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local curWeight = 0
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for i = 1, #weights do
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local weight = weights[i]
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curWeight = curWeight + weight
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if rand < curWeight then
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return i
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end
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end
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return #weights
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end
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function XMath.Clamp(value, min, max)
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if value < min then
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return min
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end
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if value > max then
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return max
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end
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return value
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end
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--==============================--
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--desc: 转换成整数，浮点数四舍五入
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--==============================--
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XMath.ToInt = function(val)
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if not val then return end
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return mathFloor(val + 0.5)
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end
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--==============================--
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--desc: 转换成整数，浮点数向下取整数
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--==============================--
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XMath.ToMinInt = function(val)
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if not val then return end
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return mathFloor(val)
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end
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--==============================--
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--desc: 最大整数，与C#一致
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--==============================--
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XMath.IntMax = function()
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return 2147483647
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end |