gononono64
84480f8939
Ripped a part utility folder and shoved it into a lib. Changed a lot of Utility prefixes to the modules name. This contains breaking changes. Scripts that use 0.2.0 will need to update to match the new format
111 lines
2.8 KiB
Lua
111 lines
2.8 KiB
Lua
local Perlin = {}
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-- Permutation table for random gradients
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local perm = {}
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local grad3 = {
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{1,1,0}, {-1,1,0}, {1,-1,0}, {-1,-1,0},
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{1,0,1}, {-1,0,1}, {1,0,-1}, {-1,0,-1},
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{0,1,1}, {0,-1,1}, {0,1,-1}, {0,-1,-1}
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}
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-- Initialize permutation table
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local function ShufflePermutation()
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local p = {}
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for i = 0, 255 do
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p[i] = i
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end
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for i = 255, 1, -1 do
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local j = math.random(i + 1) - 1
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p[i], p[j] = p[j], p[i]
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end
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for i = 0, 255 do
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perm[i] = p[i]
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perm[i + 256] = p[i] -- Repeat for wrapping
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end
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end
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ShufflePermutation() -- Randomize on load
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-- Dot product helper
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local function Dot(g, x, y, z)
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return g[1] * x + g[2] * y + (z and g[3] * z or 0)
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end
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-- Fade function (smootherstep)
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local function Fade(t)
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return t * t * t * (t * (t * 6 - 15) + 10)
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end
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-- Linear interpolation
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local function Lerp(a, b, t)
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return a + (b - a) * t
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end
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-- **Perlin Noise 1D**
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function Perlin.Noise1D(x)
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local X = math.floor(x) & 255
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x = x - math.floor(x)
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local u = Fade(x)
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local a = perm[X]
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local b = perm[X + 1]
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return Lerp(a, b, u) * (2 / 255) - 1
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end
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-- **Perlin Noise 2D**
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function Perlin.Noise2D(x, y)
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local X = math.floor(x) & 255
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local Y = math.floor(y) & 255
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x, y = x - math.floor(x), y - math.floor(y)
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local u, v = Fade(x), Fade(y)
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local aa = perm[X] + Y
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local ab = perm[X] + Y + 1
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local ba = perm[X + 1] + Y
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local bb = perm[X + 1] + Y + 1
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return Lerp(
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Lerp(Dot(grad3[perm[aa] % 12 + 1], x, y), Dot(grad3[perm[ba] % 12 + 1], x - 1, y), u),
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Lerp(Dot(grad3[perm[ab] % 12 + 1], x, y - 1), Dot(grad3[perm[bb] % 12 + 1], x - 1, y - 1), u),
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v
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)
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end
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-- **Perlin Noise 3D**
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function Perlin.Noise3D(x, y, z)
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local X = math.floor(x) & 255
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local Y = math.floor(y) & 255
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local Z = math.floor(z) & 255
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x, y, z = x - math.floor(x), y - math.floor(y), z - math.floor(z)
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local u, v, w = Fade(x), Fade(y), Fade(z)
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local aaa = perm[X] + Y + Z
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local aba = perm[X] + Y + Z + 1
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local aab = perm[X] + Y + 1 + Z
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local abb = perm[X] + Y + 1 + Z + 1
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local baa = perm[X + 1] + Y + Z
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local bba = perm[X + 1] + Y + Z + 1
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local bab = perm[X + 1] + Y + 1 + Z
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local bbb = perm[X + 1] + Y + 1 + Z + 1
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return Lerp(
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Lerp(
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Lerp(Dot(grad3[perm[aaa] % 12 + 1], x, y, z), Dot(grad3[perm[baa] % 12 + 1], x - 1, y, z), u),
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Lerp(Dot(grad3[perm[aab] % 12 + 1], x, y - 1, z), Dot(grad3[perm[bab] % 12 + 1], x - 1, y - 1, z), u),
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v
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),
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Lerp(
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Lerp(Dot(grad3[perm[aba] % 12 + 1], x, y, z - 1), Dot(grad3[perm[bba] % 12 + 1], x - 1, y, z - 1), u),
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Lerp(Dot(grad3[perm[abb] % 12 + 1], x, y - 1, z - 1), Dot(grad3[perm[bbb] % 12 + 1], x - 1, y - 1, z - 1), u),
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v
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),
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w
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)
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end
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exports('Perlin', Perlin)
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return Perlin
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