Source code for noisemaker.simplex

from __future__ import annotations

import math

import numpy as np
import tensorflow as tf

import noisemaker.rng as rng

_seed = None


[docs] def set_seed(s: int) -> None: """ Set the global simplex noise seed. Args: s: Random seed value """ global _seed _seed = s & 0xFFFFFFFF
[docs] def get_seed() -> int: """ Get the current simplex noise seed, generating one if needed. Returns: Current seed value """ global _seed if _seed is None: _seed = rng.random_int(1, 65536) else: _seed = (_seed + 1) & 0xFFFFFFFF return _seed
STRETCH_CONSTANT_2D = -0.211324865405187 SQUISH_CONSTANT_2D = 0.366025403784439 STRETCH_CONSTANT_3D = -1.0 / 6.0 SQUISH_CONSTANT_3D = 1.0 / 3.0 NORM_CONSTANT_2D = 47 NORM_CONSTANT_3D = 103 GRADIENTS_2D = [ 5, 2, 2, 5, -5, 2, -2, 5, 5, -2, 2, -5, -5, -2, -2, -5, ] GRADIENTS_3D = [ -11, 4, 4, -4, 11, 4, -4, 4, 11, 11, 4, 4, 4, 11, 4, 4, 4, 11, -11, -4, 4, -4, -11, 4, -4, -4, 11, 11, -4, 4, 4, -11, 4, 4, -4, 11, -11, 4, -4, -4, 11, -4, -4, 4, -11, 11, 4, -4, 4, 11, -4, 4, 4, -11, -11, -4, -4, -4, -11, -4, -4, -4, -11, 11, -4, -4, 4, -11, -4, 4, -4, -11, ] def _build_permutations(seed: int) -> tuple[list[int], list[int]]: """ Build permutation tables for simplex noise. Args: seed: Random seed for generating permutations Returns: Tuple of (permutation_table, gradient_index_table) """ perm = [0] * 256 perm_grad_index_3D = [0] * 256 source = list(range(256)) r = rng.Random(seed) grad_len = len(GRADIENTS_3D) // 3 for i in range(255, -1, -1): idx = r.random_int(0, i) perm[i] = source[idx] perm_grad_index_3D[i] = (perm[i] % grad_len) * 3 source[idx] = source[i] return perm, perm_grad_index_3D
[docs] class OpenSimplex:
[docs] def __init__(self, seed: int = 0) -> None: """ Initialize OpenSimplex noise generator. Args: seed: Random seed value, default 0 """ perm, perm_grad_index_3D = _build_permutations(seed) self.perm = perm self.perm_grad_index_3D = perm_grad_index_3D
def _extrapolate2d(self, xsb: int, ysb: int, dx: float, dy: float) -> float: """ Extrapolate 2D simplex noise gradient contribution. Args: xsb: X simplex base coordinate ysb: Y simplex base coordinate dx: X distance from base dy: Y distance from base Returns: Gradient contribution value """ perm = self.perm index = perm[(perm[xsb & 0xFF] + ysb) & 0xFF] & 0x0E g1 = GRADIENTS_2D[index] g2 = GRADIENTS_2D[index + 1] return g1 * dx + g2 * dy def _extrapolate3d(self, xsb: int, ysb: int, zsb: int, dx: float, dy: float, dz: float) -> float: """ Extrapolate 3D simplex noise gradient contribution. Args: xsb: X simplex base coordinate ysb: Y simplex base coordinate zsb: Z simplex base coordinate dx: X distance from base dy: Y distance from base dz: Z distance from base Returns: Gradient contribution value """ perm = self.perm index = self.perm_grad_index_3D[(perm[(perm[xsb & 0xFF] + ysb) & 0xFF] + zsb) & 0xFF] g1 = GRADIENTS_3D[index] g2 = GRADIENTS_3D[index + 1] g3 = GRADIENTS_3D[index + 2] return g1 * dx + g2 * dy + g3 * dz
[docs] def noise2d(self, x: float, y: float) -> float: """ Generate 2D OpenSimplex noise value. Args: x: X coordinate y: Y coordinate Returns: Noise value in range approximately [-1, 1] """ stretch_offset = (x + y) * STRETCH_CONSTANT_2D xs = x + stretch_offset ys = y + stretch_offset xsb = math.floor(xs) ysb = math.floor(ys) squish_offset = (xsb + ysb) * SQUISH_CONSTANT_2D xb = xsb + squish_offset yb = ysb + squish_offset xins = xs - xsb yins = ys - ysb in_sum = xins + yins dx0 = x - xb dy0 = y - yb value = 0.0 dx1 = dx0 - 1 - SQUISH_CONSTANT_2D dy1 = dy0 - SQUISH_CONSTANT_2D attn1 = 2 - dx1 * dx1 - dy1 * dy1 if attn1 > 0: attn1 *= attn1 value += attn1 * attn1 * self._extrapolate2d(xsb + 1, ysb, dx1, dy1) dx2 = dx0 - SQUISH_CONSTANT_2D dy2 = dy0 - 1 - SQUISH_CONSTANT_2D attn2 = 2 - dx2 * dx2 - dy2 * dy2 if attn2 > 0: attn2 *= attn2 value += attn2 * attn2 * self._extrapolate2d(xsb, ysb + 1, dx2, dy2) if in_sum <= 1: zins = 1 - in_sum if zins > xins or zins > yins: if xins > yins: xsv_ext = xsb + 1 ysv_ext = ysb - 1 dx_ext = dx0 - 1 dy_ext = dy0 + 1 else: xsv_ext = xsb - 1 ysv_ext = ysb + 1 dx_ext = dx0 + 1 dy_ext = dy0 - 1 else: xsv_ext = xsb + 1 ysv_ext = ysb + 1 dx_ext = dx0 - 1 - 2 * SQUISH_CONSTANT_2D dy_ext = dy0 - 1 - 2 * SQUISH_CONSTANT_2D else: zins = 2 - in_sum if zins < xins or zins < yins: if xins > yins: xsv_ext = xsb + 2 ysv_ext = ysb dx_ext = dx0 - 2 - 2 * SQUISH_CONSTANT_2D dy_ext = dy0 - 2 * SQUISH_CONSTANT_2D else: xsv_ext = xsb ysv_ext = ysb + 2 dx_ext = dx0 - 2 * SQUISH_CONSTANT_2D dy_ext = dy0 - 2 - 2 * SQUISH_CONSTANT_2D else: xsv_ext = xsb ysv_ext = ysb dx_ext = dx0 dy_ext = dy0 xsb += 1 ysb += 1 dx0 = dx0 - 1 - 2 * SQUISH_CONSTANT_2D dy0 = dy0 - 1 - 2 * SQUISH_CONSTANT_2D attn0 = 2 - dx0 * dx0 - dy0 * dy0 if attn0 > 0: attn0 *= attn0 value += attn0 * attn0 * self._extrapolate2d(xsb, ysb, dx0, dy0) attn_ext = 2 - dx_ext * dx_ext - dy_ext * dy_ext if attn_ext > 0: attn_ext *= attn_ext value += attn_ext * attn_ext * self._extrapolate2d(xsv_ext, ysv_ext, dx_ext, dy_ext) return value / NORM_CONSTANT_2D
[docs] def noise3d(self, x: float, y: float, z: float) -> float: """ Generate 3D OpenSimplex noise value. Args: x: X coordinate y: Y coordinate z: Z coordinate Returns: Noise value in range approximately [-1, 1] """ stretch_offset = (x + y + z) * STRETCH_CONSTANT_3D xs = x + stretch_offset ys = y + stretch_offset zs = z + stretch_offset xsb = math.floor(xs) ysb = math.floor(ys) zsb = math.floor(zs) squish_offset = (xsb + ysb + zsb) * SQUISH_CONSTANT_3D dx0 = x - (xsb + squish_offset) dy0 = y - (ysb + squish_offset) dz0 = z - (zsb + squish_offset) xins = xs - xsb yins = ys - ysb zins = zs - zsb in_sum = xins + yins + zins value = 0.0 if in_sum <= 1: a_point = 0x01 a_score = xins b_point = 0x02 b_score = yins if a_score >= b_score and zins > b_score: b_score = zins b_point = 0x04 elif a_score < b_score and zins > a_score: a_score = zins a_point = 0x04 wins = 1 - in_sum if wins > a_score or wins > b_score: c = b_point if b_score > a_score else a_point if c & 0x01 == 0: xsv_ext0 = xsb - 1 xsv_ext1 = xsb dx_ext0 = dx0 + 1 dx_ext1 = dx0 else: xsv_ext0 = xsv_ext1 = xsb + 1 dx_ext0 = dx_ext1 = dx0 - 1 if c & 0x02 == 0: ysv_ext0 = ysv_ext1 = ysb dy_ext0 = dy_ext1 = dy0 if c & 0x01 == 0: ysv_ext1 -= 1 dy_ext1 += 1 else: ysv_ext0 -= 1 dy_ext0 += 1 else: ysv_ext0 = ysv_ext1 = ysb + 1 dy_ext0 = dy_ext1 = dy0 - 1 if c & 0x04 == 0: zsv_ext0 = zsb zsv_ext1 = zsb - 1 dz_ext0 = dz0 dz_ext1 = dz0 + 1 else: zsv_ext0 = zsv_ext1 = zsb + 1 dz_ext0 = dz_ext1 = dz0 - 1 else: c = a_point | b_point if c & 0x01 == 0: xsv_ext0 = xsb xsv_ext1 = xsb - 1 dx_ext0 = dx0 - 2 * SQUISH_CONSTANT_3D dx_ext1 = dx0 + 1 - SQUISH_CONSTANT_3D else: xsv_ext0 = xsv_ext1 = xsb + 1 dx_ext0 = dx0 - 1 - 2 * SQUISH_CONSTANT_3D dx_ext1 = dx0 - 1 - SQUISH_CONSTANT_3D if c & 0x02 == 0: ysv_ext0 = ysb ysv_ext1 = ysb - 1 dy_ext0 = dy0 - 2 * SQUISH_CONSTANT_3D dy_ext1 = dy0 + 1 - SQUISH_CONSTANT_3D else: ysv_ext0 = ysv_ext1 = ysb + 1 dy_ext0 = dy0 - 1 - 2 * SQUISH_CONSTANT_3D dy_ext1 = dy0 - 1 - SQUISH_CONSTANT_3D if c & 0x04 == 0: zsv_ext0 = zsb zsv_ext1 = zsb - 1 dz_ext0 = dz0 - 2 * SQUISH_CONSTANT_3D dz_ext1 = dz0 + 1 - SQUISH_CONSTANT_3D else: zsv_ext0 = zsv_ext1 = zsb + 1 dz_ext0 = dz0 - 1 - 2 * SQUISH_CONSTANT_3D dz_ext1 = dz0 - 1 - SQUISH_CONSTANT_3D attn0 = 2 - dx0 * dx0 - dy0 * dy0 - dz0 * dz0 if attn0 > 0: attn0 *= attn0 value += attn0 * attn0 * self._extrapolate3d(xsb, ysb, zsb, dx0, dy0, dz0) dx1 = dx0 - 1 - SQUISH_CONSTANT_3D dy1 = dy0 - SQUISH_CONSTANT_3D dz1 = dz0 - SQUISH_CONSTANT_3D attn1 = 2 - dx1 * dx1 - dy1 * dy1 - dz1 * dz1 if attn1 > 0: attn1 *= attn1 value += attn1 * attn1 * self._extrapolate3d(xsb + 1, ysb, zsb, dx1, dy1, dz1) dx2 = dx0 - SQUISH_CONSTANT_3D dy2 = dy0 - 1 - SQUISH_CONSTANT_3D dz2 = dz1 attn2 = 2 - dx2 * dx2 - dy2 * dy2 - dz2 * dz2 if attn2 > 0: attn2 *= attn2 value += attn2 * attn2 * self._extrapolate3d(xsb, ysb + 1, zsb, dx2, dy2, dz2) dx3 = dx2 dy3 = dy1 dz3 = dz0 - 1 - SQUISH_CONSTANT_3D attn3 = 2 - dx3 * dx3 - dy3 * dy3 - dz3 * dz3 if attn3 > 0: attn3 *= attn3 value += attn3 * attn3 * self._extrapolate3d(xsb, ysb, zsb + 1, dx3, dy3, dz3) dx4 = dx0 - 1 - 2 * SQUISH_CONSTANT_3D dy4 = dy0 - 1 - 2 * SQUISH_CONSTANT_3D dz4 = dz0 - 2 * SQUISH_CONSTANT_3D attn4 = 2 - dx4 * dx4 - dy4 * dy4 - dz4 * dz4 if attn4 > 0: attn4 *= attn4 value += attn4 * attn4 * self._extrapolate3d(xsb + 1, ysb + 1, zsb, dx4, dy4, dz4) dx5 = dx4 dy5 = dy0 - 2 * SQUISH_CONSTANT_3D dz5 = dz0 - 1 - 2 * SQUISH_CONSTANT_3D attn5 = 2 - dx5 * dx5 - dy5 * dy5 - dz5 * dz5 if attn5 > 0: attn5 *= attn5 value += attn5 * attn5 * self._extrapolate3d(xsb + 1, ysb, zsb + 1, dx5, dy5, dz5) dx6 = dx0 - 2 * SQUISH_CONSTANT_3D dy6 = dy4 dz6 = dz5 attn6 = 2 - dx6 * dx6 - dy6 * dy6 - dz6 * dz6 if attn6 > 0: attn6 *= attn6 value += attn6 * attn6 * self._extrapolate3d(xsb, ysb + 1, zsb + 1, dx6, dy6, dz6) elif in_sum >= 2: a_point = 0x06 a_score = xins b_point = 0x05 b_score = yins if a_score <= b_score and zins < b_score: b_score = zins b_point = 0x03 elif a_score > b_score and zins < a_score: a_score = zins a_point = 0x03 wins = 3 - in_sum if wins < a_score or wins < b_score: c = b_point if b_score < a_score else a_point if c & 0x01: xsv_ext0 = xsb + 1 xsv_ext1 = xsb + 2 dx_ext0 = dx0 - 1 - SQUISH_CONSTANT_3D dx_ext1 = dx0 - 2 - 2 * SQUISH_CONSTANT_3D else: xsv_ext0 = xsv_ext1 = xsb dx_ext0 = dx0 - SQUISH_CONSTANT_3D dx_ext1 = dx0 - 2 * SQUISH_CONSTANT_3D if c & 0x02: ysv_ext0 = ysb + 1 ysv_ext1 = ysb + 2 dy_ext0 = dy0 - 1 - SQUISH_CONSTANT_3D dy_ext1 = dy0 - 2 - 2 * SQUISH_CONSTANT_3D else: ysv_ext0 = ysv_ext1 = ysb dy_ext0 = dy0 - SQUISH_CONSTANT_3D dy_ext1 = dy0 - 2 * SQUISH_CONSTANT_3D if c & 0x04: zsv_ext0 = zsb + 1 zsv_ext1 = zsb + 2 dz_ext0 = dz0 - 1 - SQUISH_CONSTANT_3D dz_ext1 = dz0 - 2 - 2 * SQUISH_CONSTANT_3D else: zsv_ext0 = zsv_ext1 = zsb dz_ext0 = dz0 - SQUISH_CONSTANT_3D dz_ext1 = dz0 - 2 * SQUISH_CONSTANT_3D else: c = a_point & b_point if c & 0x01: xsv_ext0 = xsb + 1 xsv_ext1 = xsb + 2 dx_ext0 = dx0 - 1 - SQUISH_CONSTANT_3D dx_ext1 = dx0 - 2 - 2 * SQUISH_CONSTANT_3D else: xsv_ext0 = xsv_ext1 = xsb dx_ext0 = dx0 - SQUISH_CONSTANT_3D dx_ext1 = dx0 - 2 * SQUISH_CONSTANT_3D if c & 0x02: ysv_ext0 = ysb + 1 ysv_ext1 = ysb + 2 dy_ext0 = dy0 - 1 - SQUISH_CONSTANT_3D dy_ext1 = dy0 - 2 - 2 * SQUISH_CONSTANT_3D else: ysv_ext0 = ysv_ext1 = ysb dy_ext0 = dy0 - SQUISH_CONSTANT_3D dy_ext1 = dy0 - 2 * SQUISH_CONSTANT_3D if c & 0x04: zsv_ext0 = zsb + 1 zsv_ext1 = zsb + 2 dz_ext0 = dz0 - 1 - SQUISH_CONSTANT_3D dz_ext1 = dz0 - 2 - 2 * SQUISH_CONSTANT_3D else: zsv_ext0 = zsv_ext1 = zsb dz_ext0 = dz0 - SQUISH_CONSTANT_3D dz_ext1 = dz0 - 2 * SQUISH_CONSTANT_3D dx3 = dx0 - 1 - 2 * SQUISH_CONSTANT_3D dy3 = dy0 - 1 - 2 * SQUISH_CONSTANT_3D dz3 = dz0 - 2 * SQUISH_CONSTANT_3D attn3 = 2 - dx3 * dx3 - dy3 * dy3 - dz3 * dz3 if attn3 > 0: attn3 *= attn3 value += attn3 * attn3 * self._extrapolate3d(xsb + 1, ysb + 1, zsb, dx3, dy3, dz3) dx2 = dx3 dy2 = dy0 - 2 * SQUISH_CONSTANT_3D dz2 = dz0 - 1 - 2 * SQUISH_CONSTANT_3D attn2 = 2 - dx2 * dx2 - dy2 * dy2 - dz2 * dz2 if attn2 > 0: attn2 *= attn2 value += attn2 * attn2 * self._extrapolate3d(xsb + 1, ysb, zsb + 1, dx2, dy2, dz2) dx1 = dx0 - 2 * SQUISH_CONSTANT_3D dy1 = dy3 dz1 = dz2 attn1 = 2 - dx1 * dx1 - dy1 * dy1 - dz1 * dz1 if attn1 > 0: attn1 *= attn1 value += attn1 * attn1 * self._extrapolate3d(xsb, ysb + 1, zsb + 1, dx1, dy1, dz1) dx0 = dx0 - 1 - 3 * SQUISH_CONSTANT_3D dy0 = dy0 - 1 - 3 * SQUISH_CONSTANT_3D dz0 = dz0 - 1 - 3 * SQUISH_CONSTANT_3D attn0 = 2 - dx0 * dx0 - dy0 * dy0 - dz0 * dz0 if attn0 > 0: attn0 *= attn0 value += attn0 * attn0 * self._extrapolate3d(xsb + 1, ysb + 1, zsb + 1, dx0, dy0, dz0) else: a_point = 0x01 a_score = xins b_point = 0x02 b_score = yins a_is_further_side = False b_is_further_side = False if a_score >= b_score and zins > b_score: b_score = zins b_point = 0x04 b_is_further_side = True elif a_score < b_score and zins > a_score: a_score = zins a_point = 0x04 a_is_further_side = True if a_score >= b_score and xins + zins > 1: a_score = xins + zins - 1 a_point = 0x03 a_is_further_side = True elif a_score < b_score and yins + zins > 1: b_score = yins + zins - 1 b_point = 0x03 b_is_further_side = True if a_is_further_side == b_is_further_side: if a_is_further_side: xsv_ext0 = xsb + 1 xsv_ext1 = xsb + 2 dx_ext0 = dx0 - 1 - SQUISH_CONSTANT_3D dx_ext1 = dx0 - 2 - 2 * SQUISH_CONSTANT_3D ysv_ext0 = ysb + 1 ysv_ext1 = ysb + 2 dy_ext0 = dy0 - 1 - SQUISH_CONSTANT_3D dy_ext1 = dy0 - 2 - 2 * SQUISH_CONSTANT_3D zsv_ext0 = zsb + 1 zsv_ext1 = zsb + 2 dz_ext0 = dz0 - 1 - SQUISH_CONSTANT_3D dz_ext1 = dz0 - 2 - 2 * SQUISH_CONSTANT_3D else: xsv_ext0 = xsb xsv_ext1 = xsb - 1 dx_ext0 = dx0 - SQUISH_CONSTANT_3D dx_ext1 = dx0 + 1 - 2 * SQUISH_CONSTANT_3D ysv_ext0 = ysb ysv_ext1 = ysb - 1 dy_ext0 = dy0 - SQUISH_CONSTANT_3D dy_ext1 = dy0 + 1 - 2 * SQUISH_CONSTANT_3D zsv_ext0 = zsb zsv_ext1 = zsb - 1 dz_ext0 = dz0 - SQUISH_CONSTANT_3D dz_ext1 = dz0 + 1 - 2 * SQUISH_CONSTANT_3D else: if a_is_further_side: c1 = a_point c2 = b_point else: c1 = b_point c2 = a_point if c1 & 0x01 == 0: xsv_ext0 = xsb dx_ext0 = dx0 - SQUISH_CONSTANT_3D else: xsv_ext0 = xsb + 1 dx_ext0 = dx0 - 1 - SQUISH_CONSTANT_3D if c1 & 0x02 == 0: ysv_ext0 = ysb dy_ext0 = dy0 - SQUISH_CONSTANT_3D else: ysv_ext0 = ysb + 1 dy_ext0 = dy0 - 1 - SQUISH_CONSTANT_3D if c1 & 0x04 == 0: zsv_ext0 = zsb dz_ext0 = dz0 - SQUISH_CONSTANT_3D else: zsv_ext0 = zsb + 1 dz_ext0 = dz0 - 1 - SQUISH_CONSTANT_3D xsv_ext1 = xsb + 1 ysv_ext1 = ysb + 1 zsv_ext1 = zsb + 1 dx_ext1 = dx0 - 1 - 2 * SQUISH_CONSTANT_3D dy_ext1 = dy0 - 1 - 2 * SQUISH_CONSTANT_3D dz_ext1 = dz0 - 1 - 2 * SQUISH_CONSTANT_3D attn0 = 2 - dx0 * dx0 - dy0 * dy0 - dz0 * dz0 if attn0 > 0: attn0 *= attn0 value += attn0 * attn0 * self._extrapolate3d(xsb, ysb, zsb, dx0, dy0, dz0) dx1 = dx0 - 1 - SQUISH_CONSTANT_3D dy1 = dy0 - SQUISH_CONSTANT_3D dz1 = dz0 - SQUISH_CONSTANT_3D attn1 = 2 - dx1 * dx1 - dy1 * dy1 - dz1 * dz1 if attn1 > 0: attn1 *= attn1 value += attn1 * attn1 * self._extrapolate3d(xsb + 1, ysb, zsb, dx1, dy1, dz1) dx2 = dx0 - SQUISH_CONSTANT_3D dy2 = dy0 - 1 - SQUISH_CONSTANT_3D dz2 = dz1 attn2 = 2 - dx2 * dx2 - dy2 * dy2 - dz2 * dz2 if attn2 > 0: attn2 *= attn2 value += attn2 * attn2 * self._extrapolate3d(xsb, ysb + 1, zsb, dx2, dy2, dz2) dx3 = dx2 dy3 = dy1 dz3 = dz0 - 1 - SQUISH_CONSTANT_3D attn3 = 2 - dx3 * dx3 - dy3 * dy3 - dz3 * dz3 if attn3 > 0: attn3 *= attn3 value += attn3 * attn3 * self._extrapolate3d(xsb, ysb, zsb + 1, dx3, dy3, dz3) attn_ext0 = 2 - dx_ext0 * dx_ext0 - dy_ext0 * dy_ext0 - dz_ext0 * dz_ext0 if attn_ext0 > 0: attn_ext0 *= attn_ext0 value += attn_ext0 * attn_ext0 * self._extrapolate3d(xsv_ext0, ysv_ext0, zsv_ext0, dx_ext0, dy_ext0, dz_ext0) attn_ext1 = 2 - dx_ext1 * dx_ext1 - dy_ext1 * dy_ext1 - dz_ext1 * dz_ext1 if attn_ext1 > 0: attn_ext1 *= attn_ext1 value += attn_ext1 * attn_ext1 * self._extrapolate3d(xsv_ext1, ysv_ext1, zsv_ext1, dx_ext1, dy_ext1, dz_ext1) return value / NORM_CONSTANT_3D
[docs] def from_seed(seed: int) -> tuple[OpenSimplex, dict[str, list[int]]]: """ Create OpenSimplex generator from seed. Args: seed: Random seed for generator initialization Returns: Tuple of (initialized OpenSimplex generator, metadata dict) """ os = OpenSimplex(seed) return os, {"perm": list(os.perm), "perm_grad": list(os.perm_grad_index_3D)}
[docs] def random(time: int | float = 0, seed: int | None = None, speed: int | float = 1) -> float: """ Create time-evolving OpenSimplex noise value. Args: time: Time offset for seed evolution, default 0 seed: Optional random seed (uses global if None), default None speed: Seed evolution speed multiplier, default 1 Returns: Random float value between 0 and 1 """ angle = math.pi * 2 * time z = math.cos(angle) * speed w = math.sin(angle) * speed s = seed if seed is not None else rng.random_int(1, 65536) os, _ = from_seed(s) value = os.noise2d(z, w) return (value + 1) * 0.5
[docs] def simplex(shape, time: int | float = 0, seed: int | None = None, speed: int | float = 1, as_np: bool = False) -> tf.Tensor | np.ndarray: """ Generate simplex noise tensor. Args: shape: Output tensor shape time: Time offset for noise evolution, default 0 seed: Optional random seed (uses global if None), default None speed: Noise evolution speed multiplier, default 1 as_np: Return as NumPy array instead of Tensor, default False Returns: Simplex noise tensor or array with values in range approximately [-1, 1] """ height, width = shape[0], shape[1] channels = shape[2] if len(shape) > 2 else 1 base_seed = seed if seed is not None else get_seed() # (z, w) traces a circle of radius `speed` so the loop visits unique noise # states; otherwise z = cos alone palindromes around t=0.5 (noise(t)==noise(1-t)). # Wrap time to [0,1) so sin/cos are exact at integer times; otherwise # math.sin(2π) ≈ -2.45e-16 nudges integer y across a lattice boundary. fractional_time = time - math.floor(time) angle = math.tau * fractional_time z = math.cos(angle) * speed w = math.sin(angle) * speed data = np.empty((height, width, channels), dtype=np.float32) for c in range(channels): os, _ = from_seed(base_seed + c * 65535) for y in range(height): for x in range(width): val = os.noise3d(x, y + w, z) data[y][x][c] = (val + 1) * 0.5 if not as_np: data = tf.stack(data) return data