API reference / @jsprismarine/worldgen / XoroshiroRandomSource

Class: XoroshiroRandomSource

Defined in: random/XoroshiroRandomSource.ts:120

A RandomSource running Xoroshiro128++ over 32-bit lanes.

Bit-for-bit equal to Xoroshiro128PlusPlus, which stays the slow reference this is tested against; the lanes avoid a BigInt allocation per operation, which matters because the aquifer and the ore vein rule build one of these per visited cell.

Implements

• RandomSource

Constructors

Constructor

new XoroshiroRandomSource(seedLo, seedHi): XoroshiroRandomSource

Defined in: random/XoroshiroRandomSource.ts:150

Parameters

seedLo

bigint

seedHi

bigint

Returns

XoroshiroRandomSource

Methods

consumeCount()

consumeCount(rounds): void

Defined in: random/XoroshiroRandomSource.ts:275

Advances the stream by rounds draws without returning them.

Parameters

rounds

number

Returns

void

Implementation of

RandomSource.consumeCount

---

fork()

fork(): RandomSource

Defined in: random/XoroshiroRandomSource.ts:280

Returns an independent stream seeded from this one, advancing this one.

Returns

RandomSource

Implementation of

RandomSource.fork

---

forkPositional()

forkPositional(): PositionalRandomFactory

Defined in: random/XoroshiroRandomSource.ts:285

Returns a positional factory seeded from this stream, advancing it.

Returns

PositionalRandomFactory

Implementation of

RandomSource.forkPositional

---

nextBits()

nextBits(bits): number

Defined in: random/XoroshiroRandomSource.ts:217

Returns the high bits from the next output without constructing a 64-bit bigint.

Parameters

bits

number

Returns

number

---

nextBoolean()

nextBoolean(): boolean

Defined in: random/XoroshiroRandomSource.ts:251

Returns the next boolean, taken from one bit of the stream.

Returns

boolean

Implementation of

RandomSource.nextBoolean

---

nextDouble()

nextDouble(): number

Defined in: random/XoroshiroRandomSource.ts:263

Returns the next value in [0, 1) with 53 bits of precision.

Returns

number

Implementation of

RandomSource.nextDouble

---

nextFloat()

nextFloat(): number

Defined in: random/XoroshiroRandomSource.ts:257

Returns the next value in [0, 1) with 24 bits of precision.

Returns

number

Implementation of

RandomSource.nextFloat

---

nextGaussian()

nextGaussian(): number

Defined in: random/XoroshiroRandomSource.ts:269

Returns the next normally distributed value with mean 0 and standard deviation 1.

Returns

number

Implementation of

RandomSource.nextGaussian

---

nextInt()

nextInt(): number

Defined in: random/XoroshiroRandomSource.ts:228

Returns the next 32-bit signed integer, with every value equally likely.

Returns

number

Implementation of

RandomSource.nextInt

---

nextIntBounded()

nextIntBounded(bound): number

Defined in: random/XoroshiroRandomSource.ts:234

Returns the next integer in [0, bound).

Parameters

bound

number

Returns

number

Throws

When bound is not positive, as Java does.

Implementation of

RandomSource.nextIntBounded

---

nextLong()

nextLong(): bigint

Defined in: random/XoroshiroRandomSource.ts:211

Returns the next 64-bit signed integer.

Returns

bigint

Implementation of

RandomSource.nextLong

---

restoreState()

restoreState(state): void

Defined in: random/XoroshiroRandomSource.ts:180

Restores this source from a JSON-parsed state, rejecting invalid lanes and fixed points.

Parameters

state

unknown

Returns

void

---

saveState()

saveState(): XoroshiroRandomSourceState

Defined in: random/XoroshiroRandomSource.ts:166

Returns the four unsigned state lanes and cached Gaussian value for replay.

Returns

XoroshiroRandomSourceState

---

fromLanes()

static fromLanes(loHi, loLo, hiHi, hiLo): XoroshiroRandomSource

Defined in: random/XoroshiroRandomSource.ts:140

Builds a source from a 128-bit state given as four unsigned 32-bit lanes.

Parameters

loHi

number

loLo

number

hiHi

number

hiLo

number

Returns

XoroshiroRandomSource

---

fromSeed()

static fromSeed(seed): XoroshiroRandomSource

Defined in: random/XoroshiroRandomSource.ts:135

Builds a source from a world seed, spreading it to 128 bits the way Java does.

Parameters

seed

bigint

Returns

XoroshiroRandomSource

---

fromState()

static fromState(state): XoroshiroRandomSource

Defined in: random/XoroshiroRandomSource.ts:130

Builds a source from a 128-bit state, which fork and the positional factory produce.

Parameters

state

Seed128bit

Returns

XoroshiroRandomSource