Difference between revisions of "FractalNoise"

(minor edit to the code, added comments.)
m (Actually edit the category description so it reflects the changes.)
 
(One intermediate revision by the same user not shown)
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<source lang="lua">
 
<source lang="lua">
-- x, y, z are the positions to sample
+
-- x, y, z, w are the positions to sample
 
-- iter is how many iterations (octaves) of the noise (default: 1)
 
-- iter is how many iterations (octaves) of the noise (default: 1)
 
-- amp is the amplitude factor (default: 0.5)
 
-- amp is the amplitude factor (default: 0.5)
 
-- freq is the frequency factor (default: 2)
 
-- freq is the frequency factor (default: 2)
 +
 +
-- returns a fractal noise value in the range [-1.0, 1.0]
 +
function genFractalNoise1(x, iter, amp, freq)
 +
val = love.math.noise(x)*2-1
 +
freq = freq or 2
 +
iter = iter or 1
 +
amp = amp or 0.5
 +
local n = 0
 +
while n < iter-1 do
 +
val = val + (love.math.noise(x*freq)*2-1)*amp
 +
freq = freq * freq
 +
amp = amp * amp
 +
n = n + 1
 +
end
 +
return math.max(math.min(val, 1.0), -1.0)
 +
end
  
 
-- returns a fractal noise value in the range [-1.0, 1.0]
 
-- returns a fractal noise value in the range [-1.0, 1.0]
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while n < iter-1 do
 
while n < iter-1 do
 
val = val + (love.math.noise(x*freq, y*freq, z*freq)*2-1)*amp
 
val = val + (love.math.noise(x*freq, y*freq, z*freq)*2-1)*amp
 +
freq = freq * freq
 +
amp = amp * amp
 +
n = n + 1
 +
end
 +
return math.max(math.min(val, 1.0), -1.0)
 +
end
 +
 +
-- returns a fractal noise value in the range [-1.0, 1.0]
 +
function genFractalNoise4(x, y, z, w, iter, amp, freq)
 +
local val = love.math.noise(x, y, z, w)*2-1
 +
freq = freq or 2
 +
iter = iter or 1
 +
amp = amp or 0.5
 +
local n = 0
 +
while n < iter-1 do
 +
val = val + (love.math.noise(x*freq, y*freq, z*freq, w*freq)*2-1)*amp
 
freq = freq * freq
 
freq = freq * freq
 
amp = amp * amp
 
amp = amp * amp
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end
 
end
 
</source>
 
</source>
 
== Contributors ==
 
* [[User:Substitute541|Substitute541]]
 
  
 
[[Category:Snippets]]
 
[[Category:Snippets]]
 
{{#set:Author=User:Substitute541}}
 
{{#set:Author=User:Substitute541}}
{{#set:Description=Generates 2 or 3 dimensional fractal noise}}
+
{{#set:LOVE Version=>0.9.0}}
 +
{{#set:Description=Generates 1, 2, 3 or 4 dimensional fractal noise}}

Latest revision as of 17:43, 11 November 2016

Generates a fractal noise using LOVE's noise functions

-- x, y, z, w are the positions to sample
-- iter is how many iterations (octaves) of the noise (default: 1)
-- amp is the amplitude factor (default: 0.5)
-- freq is the frequency factor (default: 2)

-- returns a fractal noise value in the range [-1.0, 1.0]
function genFractalNoise1(x, iter, amp, freq)
	val = love.math.noise(x)*2-1
	freq = freq or 2
	iter = iter or 1
	amp = amp or 0.5
	local n = 0
	while n < iter-1 do
		val = val + (love.math.noise(x*freq)*2-1)*amp
		freq = freq * freq
		amp = amp * amp
		n = n + 1
	end
	return math.max(math.min(val, 1.0), -1.0)
end

-- returns a fractal noise value in the range [-1.0, 1.0]
function genFractalNoise2(x, y, iter, amp, freq)
	val = love.math.noise(x, y)*2-1
	freq = freq or 2
	iter = iter or 1
	amp = amp or 0.5
	local n = 0
	while n < iter-1 do
		val = val + (love.math.noise(x*freq, y*freq)*2-1)*amp
		freq = freq * freq
		amp = amp * amp
		n = n + 1
	end
	return math.max(math.min(val, 1.0), -1.0)
end

-- returns a fractal noise value in the range [-1.0, 1.0]
function genFractalNoise3(x, y, z, iter, amp, freq)
	local val = love.math.noise(x, y, z)*2-1
	freq = freq or 2
	iter = iter or 1
	amp = amp or 0.5
	local n = 0
	while n < iter-1 do
		val = val + (love.math.noise(x*freq, y*freq, z*freq)*2-1)*amp
		freq = freq * freq
		amp = amp * amp
		n = n + 1
	end
	return math.max(math.min(val, 1.0), -1.0)
end

-- returns a fractal noise value in the range [-1.0, 1.0]
function genFractalNoise4(x, y, z, w, iter, amp, freq)
	local val = love.math.noise(x, y, z, w)*2-1
	freq = freq or 2
	iter = iter or 1
	amp = amp or 0.5
	local n = 0
	while n < iter-1 do
		val = val + (love.math.noise(x*freq, y*freq, z*freq, w*freq)*2-1)*amp
		freq = freq * freq
		amp = amp * amp
		n = n + 1
	end
	return math.max(math.min(val, 1.0), -1.0)
end