ExprUtils
Inherits Double2DParam
Synopsis
Various functions useful for expressions. Most noise functions have been taken from the Walt Disney Animation Studio SeExpr library.
Functions
def
boxstep
(x,a)def
linearstep
(x,a,b)def
smoothstep
(x,a,b)def
gaussstep
(x,a,b)def
remap
(x,source,range,falloff,interp)def
mix
(x,y,alpha)def
hash
(args)def
noise
(x)def
noise
(p)def
noise
(p)def
noise
(p)def
snoise
(p)def
vnoise
(p)def
cnoise
(p)def
snoise4
(p)def
vnoise4
(p)def
cnoise4
(p)def
turbulence
(p[,ocaves=6, lacunarity=2, gain=0.5])def
vturbulence
(p[,ocaves=6, lacunarity=2, gain=0.5])def
cturbulence
(p[,ocaves=6, lacunarity=2, gain=0.5])def
fbm
(p[,ocaves=6, lacunarity=2, gain=0.5])def
vfbm
(p[,ocaves=6, lacunarity=2, gain=0.5])def
fbm4
(p[,ocaves=6, lacunarity=2, gain=0.5])def
vfbm4
(p[,ocaves=6, lacunarity=2, gain=0.5])def
cfbm
(p[,ocaves=6, lacunarity=2, gain=0.5])def
cfbm4
(p[,ocaves=6, lacunarity=2, gain=0.5])def
cellnoise
(p)def
ccellnoise
(p)def
pnoise
(p, period)
Member functions description
 NatronEngine.ExprUtils.boxstep(x, a)
 Parameters
x –
float
a –
float
 Return type
float
if x < a then 0 otherwise 1
 NatronEngine.ExprUtils.linearstep(x, a, b)
 Parameters
x –
float
a –
float
b –
float
 Return type
float
Transitions linearly when a < x < b
 NatronEngine.ExprUtils.boxstep(x, a, b)
 Parameters
x –
float
a –
float
b –
float
 Return type
float
Transitions smoothly (cubic) when a < x < b
 NatronEngine.ExprUtils.gaussstep(x, a, b)
 Parameters
x –
float
a –
float
b –
float
 Return type
float
Transitions smoothly (exponentially) when a < x < b
 NatronEngine.ExprUtils.remap(x, source, range, falloff, interp)
 Parameters
x –
float
source –
float
range –
float
falloff –
float
interp –
float
 Return type
float
General remapping function. When x is within +/ range of source, the result is 1. The result falls to 0 beyond that range over falloff distance. The falloff shape is controlled by interp: linear = 0 smooth = 1 gaussian = 2
 NatronEngine.ExprUtils.mix(x, y, alpha)
 Parameters
x –
float
y –
float
alpha –
float
 Return type
float
Linear interpolation of a and b according to alpha
 NatronEngine.ExprUtils.hash(args)
 Parameters
args –
Sequence
 Return type
float
Like random, but with no internal seeds. Any number of seeds may be given and the result will be a random function based on all the seeds.
 NatronEngine.ExprUtils.noise(x)
 Parameters
x –
float
 Return type
float
Original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.noise(p)
 Parameters
p –
Double2DTuple
 Return type
float
Original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.noise(p)
 Parameters
p –
Double3DTuple
 Return type
float
Original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.noise(p)
 Parameters
p –
ColorTuple
 Return type
float
Original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.snoise(p)
 Parameters
p –
Double3DTuple
 Return type
float
Signed noise w/ range 1 to 1 formed with original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.vnoise(p)
 Parameters
p –
Double3DTuple
 Return type
Vector noise formed with original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.cnoise(p)
 Parameters
p –
Double3DTuple
 Return type
Color noise formed with original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.snoise4(p)
 Parameters
p –
ColorTuple
 Return type
float
4D signed noise w/ range 1 to 1 formed with original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.vnoise4(p)
 Parameters
p –
ColorTuple
 Return type
4D vector noise formed with original perlin noise at location (C2 interpolant)
 NatronEngine.ExprUtils.cnoise4(p)
 Parameters
p –
ColorTuple
 Return type
4D color noise formed with original perlin noise at location (C2 interpolant)”
 NatronEngine.ExprUtils.turbulence(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type
float
FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.vturbulence(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.cturbulence(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.fbm(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type
float
FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.vfbm(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.fbm4(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type
float
FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.vfbm4(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.cfbm(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.cfbm4(p[, ocaves=6, lacunarity=2, gain=0.5])
 Parameters
p –
Double3DTuple
octaves –
int
lacunarity –
float
gain –
float
 Return type

FBM (Fractal Brownian Motion) is a multifrequency noise function. The base frequency is the same as the noise function. The total number of frequencies is controlled by octaves. The lacunarity is the spacing between the frequencies  A value of 2 means each octave is twice the previous frequency. The gain controls how much each frequency is scaled relative to the previous frequency.
 NatronEngine.ExprUtils.cellnoise(p)
 Parameters
p –
Double3DTuple
 Return type
float
cellnoise generates a field of constant colored cubes based on the integer location This is the same as the prman cellnoise function
 NatronEngine.ExprUtils.ccellnoise(p)
 Parameters
p –
Double3DTuple
 Return type
cellnoise generates a field of constant colored cubes based on the integer location This is the same as the prman cellnoise function
 NatronEngine.ExprUtils.pnoise(p, period)
 Parameters
p –
Double3DTuple
period –
Double3DTuple
 Return type
float
Periodic noise