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Starbeamrainbowlabs
fd5804dd9c
Specifically, I'm unsure about whether I'm happy with the effects of the algorithm. Also, we convolve with a 3x3 gaussian kernel after erosion is complete - and we have verified that the erosion is having an positive effect at "roughening up" a terrain surface. It seems like the initial blog post was correct: the algorithm does tend to make steep surfaces steeper. It also appears that it's more effective on larger areas, and 'gentler' curves. THis might be because the surface normals are more conducive to making the snowballs roll. Finally, we need to decide whether we want to keep the precomputed normals as we have now, or whether we want to dynamically compute them at the some of request.
43 lines
1.2 KiB
Lua
43 lines
1.2 KiB
Lua
worldeditadditions.vector = {}
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function worldeditadditions.vector.tostring(v)
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return "(" .. v.x ..", " .. v.y ..", " .. v.z ..")"
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end
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-- Calculates the length squared of the given vector.
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-- @param v Vector The vector to operate on
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-- @return number The length of the given vector squared
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function worldeditadditions.vector.lengthsquared(v)
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if not v.y then return v.x*v.x + v.z*v.z end
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return v.x*v.x + v.y*v.y + v.z*v.z
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end
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--- Normalises the given vector such that its length is 1.
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-- Also known as calculating the unit vector.
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-- This method does *not* mutate.
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-- @param v Vector The vector to calculate from.
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-- @return Vector A new normalised vector.
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function worldeditadditions.vector.normalize(v)
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local length = math.sqrt(worldeditadditions.vector.lengthsquared(v))
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if not v.y then return {
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x = v.x / length,
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z = v.z / length
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} end
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return {
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x = v.x / length,
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y = v.y / length,
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z = v.z / length
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}
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end
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--- Rounds the values in a vector down.
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-- Warning: This MUTATES the given vector!
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-- @param v Vector The vector to operate on
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function worldeditadditions.vector.floor(v)
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v.x = math.floor(v.x)
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-- Some vectors are 2d, but on the x / z axes
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if v.y then v.y = math.floor(v.y) end
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-- Some vectors are 2d
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if v.z then v.z = math.floor(v.z) end
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end
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