fix significant oversights in noise & random

This commit is contained in:
a dinosaur 2024-09-05 21:46:49 +10:00
parent 2a4eb2283a
commit 301aa28c4d
9 changed files with 41 additions and 55 deletions

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@ -59,7 +59,7 @@ public struct Chunk: Hashable {
let x = i & Self.mask
let y = (i &>> Self.shift) & Self.mask
let z = (i &>> (Self.shift + Self.shift)) & Self.mask
blocks[i].type = calculation(self.origin &+ SIMD3(x, y, z))
blocks[i].type = calculation(SIMD3(x, y, z))
}
}

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@ -18,7 +18,7 @@ struct StandardWorldGenerator: WorldGenerator {
let chunkOrigin = chunkID &<< Chunk.shift
var chunk = Chunk(position: chunkOrigin)
chunk.fill(allBy: { position in
let fpos = SIMD3<Float>(position)
let fpos = SIMD3<Float>(chunkOrigin &+ position)
let threshold: Float = 0.6
let value = fpos.y / 16.0
+ self.noise.get(fpos * 0.05) * 1.1

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@ -6,15 +6,15 @@ struct TerrorTowerGenerator: WorldGenerator {
public mutating func reset(seed: UInt64) {
var random = Xoroshiro128PlusPlus(state: SplitMix64.createState(seed: seed))
self.noise1 = LayeredNoise(random: &random, octaves: 4, frequency: 0.05, amplitude: 1.1)
self.noise2 = LayeredNoise(random: &random, octaves: 3, frequency: 0.1, amplitude: 0.5)
self.noise1 = LayeredNoise(random: &random, octaves: 4, frequency: 0.05, amplitude: 2.2)
self.noise2 = LayeredNoise(random: &random, octaves: 3, frequency: 0.1)
}
public func makeChunk(id chunkID: SIMD3<Int>) -> Chunk {
let chunkOrigin = chunkID &<< Chunk.shift
var chunk = Chunk(position: chunkOrigin)
chunk.fill(allBy: { position in
let fpos = SIMD3<Float>(position)
let fpos = SIMD3<Float>(chunkOrigin &+ position)
let threshold: Float = 0.6
let gradient = simd_length(fpos.xz) / 14.0
let value = self.noise1.get(fpos) - 0.25

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@ -1,13 +1,15 @@
public protocol CoherentNoise {
associatedtype Scalar: FloatingPoint & SIMDScalar
init()
}
public protocol CoherentNoiseRandomInit: CoherentNoise {
init<Random: RandomProvider>(random: inout Random)
}
public protocol CoherentNoiseTableInit: CoherentNoise {
init(permutation: [Int16])
}
public protocol CoherentNoise2D: CoherentNoise {
func get(_ point: SIMD2<Scalar>) -> Scalar
}

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@ -1,4 +1,3 @@
public struct LayeredNoise<Generator: CoherentNoise> {
public typealias Scalar = Generator.Scalar
@ -7,47 +6,55 @@ public struct LayeredNoise<Generator: CoherentNoise> {
public let amplitude: Scalar
private let _generators: [Generator]
init(octaves: Int, frequency: Scalar, amplitude: Scalar) {
self.octaves = octaves
self.frequency = frequency
self.amplitude = amplitude
self._generators = Array(repeating: .init(), count: octaves)
}
private let _amplitudeAdjusted: Scalar
}
public extension LayeredNoise where Generator: CoherentNoiseRandomInit {
init<Random: RandomProvider>(random: inout Random, octaves: Int, frequency: Scalar, amplitude: Scalar) {
init<Random: RandomProvider>(random: inout Random, octaves: Int, frequency: Scalar, amplitude: Scalar = 1) {
self.octaves = octaves
self.frequency = frequency
self.amplitude = amplitude
self._generators = Array(repeating: Generator(random: &random), count: octaves)
self._generators = (0..<octaves).map { _ in Generator(random: &random) }
self._amplitudeAdjusted = amplitude / 2
}
}
public extension LayeredNoise where Generator: CoherentNoiseTableInit {
init(permutation table: [Int16], octaves: Int, frequency: Scalar, amplitude: Scalar = 1) {
self.octaves = octaves
self.frequency = frequency
self.amplitude = amplitude
self._generators = Array(repeating: Generator(permutation: table), count: octaves)
self._amplitudeAdjusted = amplitude / 2
}
}
public extension LayeredNoise where Generator: CoherentNoise2D {
func get(_ point: SIMD2<Scalar>) -> Scalar {
zip(self._generators, 0..<self.octaves).map { layer, term in
zip(self._generators[1...], 1..<self.octaves).map { layer, term in
let mul = Scalar(1 + term)
return layer.get(point * frequency * mul) / mul
}.reduce(0) { $0 + $1 } * amplitude
return layer.get(point * self.frequency * mul) / mul
}.reduce(self._generators[0].get(point * self.frequency)) {
$0 + $1 } * self._amplitudeAdjusted
}
}
public extension LayeredNoise where Generator: CoherentNoise3D {
func get(_ point: SIMD3<Scalar>) -> Scalar {
zip(self._generators, 0..<self.octaves).map { layer, term in
zip(self._generators[1...], 1..<self.octaves).map { layer, term in
let mul = Scalar(1 + term)
return layer.get(point * frequency * mul) / mul
}.reduce(0) { $0 + $1 } * amplitude
return layer.get(point * self.frequency * mul) / mul
}.reduce(self._generators[0].get(point * self.frequency)) {
$0 + $1 } * self._amplitudeAdjusted
}
}
public extension LayeredNoise where Generator: CoherentNoise4D {
func get(_ point: SIMD4<Scalar>) -> Scalar {
zip(self._generators, 0..<self.octaves).map { layer, term in
zip(self._generators[1...], 1..<self.octaves).map { layer, term in
let mul = Scalar(1 + term)
return layer.get(point * frequency * mul) / mul
}.reduce(0) { $0 + $1 } * amplitude
return layer.get(point * self.frequency * mul) / mul
}.reduce(self._generators[0].get(point * self.frequency)) {
$0 + $1 } * self._amplitudeAdjusted
}
}

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@ -1,12 +1,8 @@
import Foundation
public struct ImprovedPerlin<Scalar: BinaryFloatingPoint & SIMDScalar>: CoherentNoise2D, CoherentNoise3D, CoherentNoiseRandomInit {
public struct ImprovedPerlin<Scalar: BinaryFloatingPoint & SIMDScalar>: CoherentNoise2D, CoherentNoise3D, CoherentNoiseRandomInit, CoherentNoiseTableInit {
private let p: [Int16]
public init() {
self.init(permutation: defaultPermutation)
}
public init(permutation: [Int16]) {
assert(permutation.count == 0x100)
self.p = permutation
@ -90,19 +86,3 @@ public struct ImprovedPerlin<Scalar: BinaryFloatingPoint & SIMDScalar>: Coherent
return u + v
}
}
internal let defaultPermutation: [Int16] = [
151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,
8, 99,37,240,21,10,23,190, 6,148,247,120,234,75, 0,26,197,62,94,252,219,203,
117,35, 11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,
165,71,134,139,48, 27,166,77,146,158,231,83,111,229,122, 60,211,133,230,220,
105,92,41,55,46,245,40,244,102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,
187,208, 89, 18,169,200,196,135,130,116,188,159, 86,164,100,109,198,173,186,
3,64,52,217,226,250,124,123, 5,202, 38,147,118,126,255,82,85,212,207,206,59,
227,47,16,58,17,182,189,28,42,223,183,170,213,119,248,152, 2,44,154,163, 70,
221,153,101,155,167, 43,172,9,129,22,39,253, 19, 98,108,110, 79,113,224,232,
178,185, 112,104,218,246,97,228,251, 34,242,193,238,210,144, 12,191,179,162,
241, 81,51,145,235,249,14,239,107,49,192,214, 31,181,199,106,157,184,84,204,
176,115,121,50,45,127, 4,150,254,138,236,205,93,222,114,67,29,24,72,243,141,
128,195,78,66,215,61,156,180
]

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@ -1,6 +1,6 @@
import Foundation
public struct SimplexNoise<Scalar: BinaryFloatingPoint & SIMDScalar>: CoherentNoise2D, CoherentNoise3D, CoherentNoise4D, CoherentNoiseRandomInit {
public struct SimplexNoise<Scalar: BinaryFloatingPoint & SIMDScalar>: CoherentNoise2D, CoherentNoise3D, CoherentNoise4D, CoherentNoiseRandomInit, CoherentNoiseTableInit {
private let p: [Int16], pMod12: [Int16]
private let grad3: [SIMD3<Scalar>] = [
@ -19,10 +19,6 @@ public struct SimplexNoise<Scalar: BinaryFloatingPoint & SIMDScalar>: CoherentNo
.init(-1, 1, 1, 0), .init(-1, 1, -1, 0), .init(-1, -1, 1, 0), .init(-1, -1, -1, 0)
]
public init() {
self.init(permutation: defaultPermutation)
}
public init(permutation: [Int16]) {
assert(permutation.count == 0x100)
self.p = permutation

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@ -1,9 +1,10 @@
public extension MutableCollection {
mutating func shuffle<T: RandomProvider>(using provider: inout T) {
guard self.count > 1 else {
let count = self.count
guard count > 1 else {
return
}
for (first, remaining) in zip(self.indices, stride(from: 0x100, to: 1, by: -1)) {
for (first, remaining) in zip(self.indices, stride(from: count, to: 1, by: -1)) {
let i = self.index(first, offsetBy: provider.next(in: remaining))
self.swapAt(first, i)
}

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@ -9,7 +9,7 @@ public class World {
private var _chunks: Dictionary<ChunkID, Chunk>
private var _chunkDamage: Set<ChunkID>
private var _generator: WorldGenerator
private var _generator: any WorldGenerator
private var _chunkGeneration: ChunkGeneration
public init() {