Files
orx/orx-noise/src/commonMain/kotlin/GradientPerturb.kt
2021-06-24 13:31:27 +02:00

126 lines
3.9 KiB
Kotlin

package org.openrndr.extra.noise
import org.openrndr.math.Vector2
import org.openrndr.math.Vector3
import org.openrndr.math.mix
fun gradientPerturbFractal(seed: Int, amplitude: Double = 1.0, frequency: Double = 2.0,
lacunarity: Double = 2.0, gain: Double = 0.5,
octaves: Int = 4, position: Vector3, interpolator: (Double) -> Double = ::quintic): Vector3 {
var seed_ = seed
var amplitude_ = amplitude
var frequency_ = frequency
var p = gradientPerturb(seed_, amplitude_, frequency_, position, interpolator)
for (i in 0 until octaves) {
frequency_ *= lacunarity
amplitude_ *= gain
seed_++
p = gradientPerturb(seed_, amplitude_, frequency_, p, interpolator)
}
return p
}
fun gradientPerturb(seed: Int, amplitude: Double, frequency: Double, position: Vector3, interpolator: (Double) -> Double = ::quintic): Vector3 {
val xf = position.x * frequency
val yf = position.y * frequency
val zf = position.z * frequency
val x0 = xf.fastFloor()
val y0 = yf.fastFloor()
val z0 = zf.fastFloor()
val x1 = x0 + 1
val y1 = y0 + 1
val z1 = z0 + 1
val xs = interpolator(xf - x0)
val ys = interpolator(yf - y0)
val zs = interpolator(zf - z0)
var vec0 = Cell3D[hash3D(seed, x0, y0, z0) and 0xff]
var vec1 = Cell3D[hash3D(seed, x1, y0, z0) and 0xff]
var lx0x = mix(vec0.x, vec1.x, xs)
var ly0x = mix(vec0.y, vec1.y, xs)
var lz0x = mix(vec0.z, vec1.z, xs)
vec0 = Cell3D[hash3D(seed, x0, y1, z0) and 0xff]
vec1 = Cell3D[hash3D(seed, x1, y1, z0) and 0xff]
var lx1x = mix(vec0.x, vec1.x, xs)
var ly1x = mix(vec0.y, vec1.y, xs)
var lz1x = mix(vec0.z, vec1.z, xs)
val lx0y = mix(lx0x, lx1x, ys)
val ly0y = mix(ly0x, ly1x, ys)
val lz0y = mix(lz0x, lz1x, ys)
vec0 = Cell3D[hash3D(seed, x0, y0, z1) and 0xff]
vec1 = Cell3D[hash3D(seed, x1, y0, z1) and 0xff]
lx0x = mix(vec0.x, vec1.x, xs)
ly0x = mix(vec0.y, vec1.y, xs)
lz0x = mix(vec0.z, vec1.z, xs)
vec0 = Cell3D[hash3D(seed, x0, y1, z1) and 0xff]
vec1 = Cell3D[hash3D(seed, x1, y1, z1) and 0xff]
lx1x = mix(vec0.x, vec1.x, xs)
ly1x = mix(vec0.y, vec1.y, xs)
lz1x = mix(vec0.z, vec1.z, xs)
return position + Vector3(
mix(lx0y, mix(lx0x, lx1x, ys), zs),
mix(ly0y, mix(ly0x, ly1x, ys), zs),
mix(lz0y, mix(lz0x, lz1x, ys), zs)
) * amplitude
}
fun gradientPerturbFractal(seed: Int, amplitude: Double = 1.0, frequency: Double = 2.0,
lacunarity: Double = 2.0, gain: Double = 0.5,
octaves: Int = 4, position: Vector2, interpolator: (Double) -> Double = ::quintic): Vector2 {
var seed_ = seed
var amplitude_ = amplitude
var frequency_ = frequency
var p = gradientPerturb(seed_, amplitude_, frequency_, position, interpolator)
for (i in 0 until octaves) {
frequency_ *= lacunarity
amplitude_ *= gain
seed_++
p = gradientPerturb(seed_, amplitude_, frequency_, p, interpolator)
}
return p
}
fun gradientPerturb(seed: Int, amplitude: Double, frequency: Double, position: Vector2, interpolator: (Double) -> Double = ::quintic): Vector2 {
val xf = position.x * frequency
val yf = position.y * frequency
val x0 = xf.fastFloor()
val y0 = yf.fastFloor()
val x1 = x0 + 1
val y1 = y0 + 1
val xs = interpolator(xf - x0)
val ys = interpolator(yf - y0)
var vec0 = Cell2D[hash2D(seed, x0, y0) and 0xff]
var vec1 = Cell2D[hash2D(seed, x1, y0) and 0xff]
val lx0x = mix(vec0.x, vec1.x, xs)
val ly0x = mix(vec0.y, vec1.y, xs)
vec0 = Cell2D[hash2D(seed, x0, y1) and 0xff]
vec1 = Cell2D[hash2D(seed, x1, y1) and 0xff]
val lx1x = mix(vec0.x, vec1.x, xs)
val ly1x = mix(vec0.y, vec1.y, xs)
return position + Vector2(
mix(lx0x, lx1x, ys),
mix(ly0x, ly1x, ys)
) * amplitude
}