mirror of
https://github.com/pmmp/PocketMine-MP.git
synced 2025-06-16 16:34:05 +00:00
ff28c982ac
the code in here isn't used anywhere except as a base for Simplex, so it makes more sense to flatten it and get rid of the crap.
473 lines
15 KiB
PHP
473 lines
15 KiB
PHP
<?php
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/*
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*
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* ____ _ _ __ __ _ __ __ ____
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* | _ \ ___ ___| | _____| |_| \/ (_)_ __ ___ | \/ | _ \
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* | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
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* | __/ (_) | (__| < __/ |_| | | | | | | | __/_____| | | | __/
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* |_| \___/ \___|_|\_\___|\__|_| |_|_|_| |_|\___| |_| |_|_|
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* @author PocketMine Team
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* @link http://www.pocketmine.net/
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*
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*
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*/
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declare(strict_types=1);
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namespace pocketmine\level\generator\noise;
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use pocketmine\utils\Random;
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/**
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* Generates simplex-based noise.
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*
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* This is a modified version of the freely published version in the paper by
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* Stefan Gustavson at
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* http://staffwww.itn.liu.se/~stegu/simplexnoise/simplexnoise.pdf
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*/
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class Simplex extends Noise{
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public static $grad3 = [
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[1, 1, 0], [-1, 1, 0], [1, -1, 0], [-1, -1, 0],
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[1, 0, 1], [-1, 0, 1], [1, 0, -1], [-1, 0, -1],
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[0, 1, 1], [0, -1, 1], [0, 1, -1], [0, -1, -1]
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];
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protected static $SQRT_3;
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protected static $SQRT_5;
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protected static $F2;
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protected static $G2;
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protected static $G22;
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protected static $F3;
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protected static $G3;
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protected static $F4;
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protected static $G4;
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protected static $G42;
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protected static $G43;
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protected static $G44;
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protected static $grad4 = [[0, 1, 1, 1], [0, 1, 1, -1], [0, 1, -1, 1], [0, 1, -1, -1],
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[0, -1, 1, 1], [0, -1, 1, -1], [0, -1, -1, 1], [0, -1, -1, -1],
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[1, 0, 1, 1], [1, 0, 1, -1], [1, 0, -1, 1], [1, 0, -1, -1],
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[-1, 0, 1, 1], [-1, 0, 1, -1], [-1, 0, -1, 1], [-1, 0, -1, -1],
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[1, 1, 0, 1], [1, 1, 0, -1], [1, -1, 0, 1], [1, -1, 0, -1],
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[-1, 1, 0, 1], [-1, 1, 0, -1], [-1, -1, 0, 1], [-1, -1, 0, -1],
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[1, 1, 1, 0], [1, 1, -1, 0], [1, -1, 1, 0], [1, -1, -1, 0],
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[-1, 1, 1, 0], [-1, 1, -1, 0], [-1, -1, 1, 0], [-1, -1, -1, 0]];
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protected static $simplex = [
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[0, 1, 2, 3], [0, 1, 3, 2], [0, 0, 0, 0], [0, 2, 3, 1], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [1, 2, 3, 0],
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[0, 2, 1, 3], [0, 0, 0, 0], [0, 3, 1, 2], [0, 3, 2, 1], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [1, 3, 2, 0],
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[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0],
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[1, 2, 0, 3], [0, 0, 0, 0], [1, 3, 0, 2], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [2, 3, 0, 1], [2, 3, 1, 0],
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[1, 0, 2, 3], [1, 0, 3, 2], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [2, 0, 3, 1], [0, 0, 0, 0], [2, 1, 3, 0],
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[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0],
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[2, 0, 1, 3], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [3, 0, 1, 2], [3, 0, 2, 1], [0, 0, 0, 0], [3, 1, 2, 0],
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[2, 1, 0, 3], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [3, 1, 0, 2], [0, 0, 0, 0], [3, 2, 0, 1], [3, 2, 1, 0]];
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protected $offsetW;
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public function __construct(Random $random, $octaves, $persistence, $expansion = 1){
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$this->octaves = $octaves;
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$this->persistence = $persistence;
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$this->expansion = $expansion;
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$this->offsetX = $random->nextFloat() * 256;
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$this->offsetY = $random->nextFloat() * 256;
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$this->offsetZ = $random->nextFloat() * 256;
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$this->offsetW = $random->nextFloat() * 256;
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for($i = 0; $i < 512; ++$i){
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$this->perm[$i] = 0;
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}
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for($i = 0; $i < 256; ++$i){
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$this->perm[$i] = $random->nextBoundedInt(256);
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}
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for($i = 0; $i < 256; ++$i){
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$pos = $random->nextBoundedInt(256 - $i) + $i;
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$old = $this->perm[$i];
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$this->perm[$i] = $this->perm[$pos];
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$this->perm[$pos] = $old;
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$this->perm[$i + 256] = $this->perm[$i];
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}
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self::$SQRT_3 = sqrt(3);
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self::$SQRT_5 = sqrt(5);
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self::$F2 = 0.5 * (self::$SQRT_3 - 1);
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self::$G2 = (3 - self::$SQRT_3) / 6;
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self::$G22 = self::$G2 * 2.0 - 1;
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self::$F3 = 1.0 / 3.0;
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self::$G3 = 1.0 / 6.0;
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self::$F4 = (self::$SQRT_5 - 1.0) / 4.0;
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self::$G4 = (5.0 - self::$SQRT_5) / 20.0;
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self::$G42 = self::$G4 * 2.0;
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self::$G43 = self::$G4 * 3.0;
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self::$G44 = self::$G4 * 4.0 - 1.0;
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}
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protected static function dot2D($g, $x, $y){
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return $g[0] * $x + $g[1] * $y;
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}
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protected static function dot3D($g, $x, $y, $z){
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return $g[0] * $x + $g[1] * $y + $g[2] * $z;
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}
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protected static function dot4D($g, $x, $y, $z, $w){
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return $g[0] * $x + $g[1] * $y + $g[2] * $z + $g[3] * $w;
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}
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public function getNoise3D($x, $y, $z){
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$x += $this->offsetX;
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$y += $this->offsetY;
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$z += $this->offsetZ;
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// Skew the input space to determine which simplex cell we're in
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$s = ($x + $y + $z) * self::$F3; // Very nice and simple skew factor for 3D
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$i = (int) ($x + $s);
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$j = (int) ($y + $s);
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$k = (int) ($z + $s);
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$t = ($i + $j + $k) * self::$G3;
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// Unskew the cell origin back to (x,y,z) space
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$x0 = $x - ($i - $t); // The x,y,z distances from the cell origin
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$y0 = $y - ($j - $t);
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$z0 = $z - ($k - $t);
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// For the 3D case, the simplex shape is a slightly irregular tetrahedron.
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// Determine which simplex we are in.
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if($x0 >= $y0){
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if($y0 >= $z0){
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$i1 = 1;
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$j1 = 0;
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$k1 = 0;
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$i2 = 1;
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$j2 = 1;
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$k2 = 0;
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} // X Y Z order
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elseif($x0 >= $z0){
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$i1 = 1;
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$j1 = 0;
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$k1 = 0;
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$i2 = 1;
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$j2 = 0;
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$k2 = 1;
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} // X Z Y order
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else{
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$i1 = 0;
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$j1 = 0;
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$k1 = 1;
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$i2 = 1;
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$j2 = 0;
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$k2 = 1;
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}
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// Z X Y order
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}else{ // x0<y0
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if($y0 < $z0){
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$i1 = 0;
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$j1 = 0;
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$k1 = 1;
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$i2 = 0;
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$j2 = 1;
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$k2 = 1;
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} // Z Y X order
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elseif($x0 < $z0){
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$i1 = 0;
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$j1 = 1;
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$k1 = 0;
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$i2 = 0;
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$j2 = 1;
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$k2 = 1;
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} // Y Z X order
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else{
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$i1 = 0;
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$j1 = 1;
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$k1 = 0;
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$i2 = 1;
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$j2 = 1;
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$k2 = 0;
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}
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// Y X Z order
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}
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// A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z),
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// a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and
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// a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where
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// c = 1/6.
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$x1 = $x0 - $i1 + self::$G3; // Offsets for second corner in (x,y,z) coords
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$y1 = $y0 - $j1 + self::$G3;
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$z1 = $z0 - $k1 + self::$G3;
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$x2 = $x0 - $i2 + 2.0 * self::$G3; // Offsets for third corner in (x,y,z) coords
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$y2 = $y0 - $j2 + 2.0 * self::$G3;
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$z2 = $z0 - $k2 + 2.0 * self::$G3;
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$x3 = $x0 - 1.0 + 3.0 * self::$G3; // Offsets for last corner in (x,y,z) coords
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$y3 = $y0 - 1.0 + 3.0 * self::$G3;
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$z3 = $z0 - 1.0 + 3.0 * self::$G3;
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// Work out the hashed gradient indices of the four simplex corners
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$ii = $i & 255;
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$jj = $j & 255;
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$kk = $k & 255;
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$n = 0;
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// Calculate the contribution from the four corners
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$t0 = 0.6 - $x0 * $x0 - $y0 * $y0 - $z0 * $z0;
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if($t0 > 0){
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$gi0 = self::$grad3[$this->perm[$ii + $this->perm[$jj + $this->perm[$kk]]] % 12];
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$n += $t0 * $t0 * $t0 * $t0 * ($gi0[0] * $x0 + $gi0[1] * $y0 + $gi0[2] * $z0);
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}
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$t1 = 0.6 - $x1 * $x1 - $y1 * $y1 - $z1 * $z1;
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if($t1 > 0){
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$gi1 = self::$grad3[$this->perm[$ii + $i1 + $this->perm[$jj + $j1 + $this->perm[$kk + $k1]]] % 12];
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$n += $t1 * $t1 * $t1 * $t1 * ($gi1[0] * $x1 + $gi1[1] * $y1 + $gi1[2] * $z1);
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}
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$t2 = 0.6 - $x2 * $x2 - $y2 * $y2 - $z2 * $z2;
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if($t2 > 0){
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$gi2 = self::$grad3[$this->perm[$ii + $i2 + $this->perm[$jj + $j2 + $this->perm[$kk + $k2]]] % 12];
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$n += $t2 * $t2 * $t2 * $t2 * ($gi2[0] * $x2 + $gi2[1] * $y2 + $gi2[2] * $z2);
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}
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$t3 = 0.6 - $x3 * $x3 - $y3 * $y3 - $z3 * $z3;
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if($t3 > 0){
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$gi3 = self::$grad3[$this->perm[$ii + 1 + $this->perm[$jj + 1 + $this->perm[$kk + 1]]] % 12];
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$n += $t3 * $t3 * $t3 * $t3 * ($gi3[0] * $x3 + $gi3[1] * $y3 + $gi3[2] * $z3);
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}
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// Add contributions from each corner to get the noise value.
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// The result is scaled to stay just inside [-1,1]
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return 32.0 * $n;
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}
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public function getNoise2D($x, $y){
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$x += $this->offsetX;
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$y += $this->offsetY;
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// Skew the input space to determine which simplex cell we're in
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$s = ($x + $y) * self::$F2; // Hairy factor for 2D
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$i = (int) ($x + $s);
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$j = (int) ($y + $s);
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$t = ($i + $j) * self::$G2;
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// Unskew the cell origin back to (x,y) space
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$x0 = $x - ($i - $t); // The x,y distances from the cell origin
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$y0 = $y - ($j - $t);
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// For the 2D case, the simplex shape is an equilateral triangle.
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// Determine which simplex we are in.
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if($x0 > $y0){
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$i1 = 1;
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$j1 = 0;
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} // lower triangle, XY order: (0,0)->(1,0)->(1,1)
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else{
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$i1 = 0;
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$j1 = 1;
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}
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// upper triangle, YX order: (0,0)->(0,1)->(1,1)
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// A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
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// a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
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// c = (3-sqrt(3))/6
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$x1 = $x0 - $i1 + self::$G2; // Offsets for middle corner in (x,y) unskewed coords
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$y1 = $y0 - $j1 + self::$G2;
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$x2 = $x0 + self::$G22; // Offsets for last corner in (x,y) unskewed coords
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$y2 = $y0 + self::$G22;
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// Work out the hashed gradient indices of the three simplex corners
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$ii = $i & 255;
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$jj = $j & 255;
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$n = 0;
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// Calculate the contribution from the three corners
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$t0 = 0.5 - $x0 * $x0 - $y0 * $y0;
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if($t0 > 0){
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$gi0 = self::$grad3[$this->perm[$ii + $this->perm[$jj]] % 12];
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$n += $t0 * $t0 * $t0 * $t0 * ($gi0[0] * $x0 + $gi0[1] * $y0); // (x,y) of grad3 used for 2D gradient
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}
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$t1 = 0.5 - $x1 * $x1 - $y1 * $y1;
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if($t1 > 0){
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$gi1 = self::$grad3[$this->perm[$ii + $i1 + $this->perm[$jj + $j1]] % 12];
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$n += $t1 * $t1 * $t1 * $t1 * ($gi1[0] * $x1 + $gi1[1] * $y1);
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}
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$t2 = 0.5 - $x2 * $x2 - $y2 * $y2;
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if($t2 > 0){
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$gi2 = self::$grad3[$this->perm[$ii + 1 + $this->perm[$jj + 1]] % 12];
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$n += $t2 * $t2 * $t2 * $t2 * ($gi2[0] * $x2 + $gi2[1] * $y2);
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}
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// Add contributions from each corner to get the noise value.
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// The result is scaled to return values in the interval [-1,1].
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return 70.0 * $n;
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}
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/**
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* Computes and returns the 4D simplex noise for the given coordinates in
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* 4D space
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*
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* @param float $x X coordinate
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* @param float $y Y coordinate
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* @param float $z Z coordinate
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* @param float $w W coordinate
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*
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* @return float Noise at given location, from range -1 to 1
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*/
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/*public function getNoise4D($x, $y, $z, $w){
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x += offsetX;
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y += offsetY;
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z += offsetZ;
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w += offsetW;
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n0, n1, n2, n3, n4; // Noise contributions from the five corners
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// Skew the (x,y,z,w) space to determine which cell of 24 simplices we're in
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s = (x + y + z + w) * self::$F4; // Factor for 4D skewing
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i = floor(x + s);
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j = floor(y + s);
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k = floor(z + s);
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l = floor(w + s);
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t = (i + j + k + l) * self::$G4; // Factor for 4D unskewing
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X0 = i - t; // Unskew the cell origin back to (x,y,z,w) space
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Y0 = j - t;
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Z0 = k - t;
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W0 = l - t;
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x0 = x - X0; // The x,y,z,w distances from the cell origin
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y0 = y - Y0;
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z0 = z - Z0;
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w0 = w - W0;
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// For the 4D case, the simplex is a 4D shape I won't even try to describe.
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// To find out which of the 24 possible simplices we're in, we need to
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// determine the magnitude ordering of x0, y0, z0 and w0.
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// The method below is a good way of finding the ordering of x,y,z,w and
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// then find the correct traversal order for the simplex we’re in.
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// First, six pair-wise comparisons are performed between each possible pair
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// of the four coordinates, and the results are used to add up binary bits
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// for an integer index.
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c1 = (x0 > y0) ? 32 : 0;
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c2 = (x0 > z0) ? 16 : 0;
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c3 = (y0 > z0) ? 8 : 0;
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c4 = (x0 > w0) ? 4 : 0;
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c5 = (y0 > w0) ? 2 : 0;
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c6 = (z0 > w0) ? 1 : 0;
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c = c1 + c2 + c3 + c4 + c5 + c6;
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i1, j1, k1, l1; // The integer offsets for the second simplex corner
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i2, j2, k2, l2; // The integer offsets for the third simplex corner
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i3, j3, k3, l3; // The integer offsets for the fourth simplex corner
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// simplex[c] is a 4-vector with the numbers 0, 1, 2 and 3 in some order.
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// Many values of c will never occur, since e.g. x>y>z>w makes x<z, y<w and x<w
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// impossible. Only the 24 indices which have non-zero entries make any sense.
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// We use a thresholding to set the coordinates in turn from the largest magnitude.
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// The number 3 in the "simplex" array is at the position of the largest coordinate.
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i1 = simplex[c][0] >= 3 ? 1 : 0;
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||
j1 = simplex[c][1] >= 3 ? 1 : 0;
|
||
k1 = simplex[c][2] >= 3 ? 1 : 0;
|
||
l1 = simplex[c][3] >= 3 ? 1 : 0;
|
||
|
||
// The number 2 in the "simplex" array is at the second largest coordinate.
|
||
i2 = simplex[c][0] >= 2 ? 1 : 0;
|
||
j2 = simplex[c][1] >= 2 ? 1 : 0;
|
||
k2 = simplex[c][2] >= 2 ? 1 : 0;
|
||
l2 = simplex[c][3] >= 2 ? 1 : 0;
|
||
|
||
// The number 1 in the "simplex" array is at the second smallest coordinate.
|
||
i3 = simplex[c][0] >= 1 ? 1 : 0;
|
||
j3 = simplex[c][1] >= 1 ? 1 : 0;
|
||
k3 = simplex[c][2] >= 1 ? 1 : 0;
|
||
l3 = simplex[c][3] >= 1 ? 1 : 0;
|
||
|
||
// The fifth corner has all coordinate offsets = 1, so no need to look that up.
|
||
|
||
x1 = x0 - i1 + self::$G4; // Offsets for second corner in (x,y,z,w) coords
|
||
y1 = y0 - j1 + self::$G4;
|
||
z1 = z0 - k1 + self::$G4;
|
||
w1 = w0 - l1 + self::$G4;
|
||
|
||
x2 = x0 - i2 + self::$G42; // Offsets for third corner in (x,y,z,w) coords
|
||
y2 = y0 - j2 + self::$G42;
|
||
z2 = z0 - k2 + self::$G42;
|
||
w2 = w0 - l2 + self::$G42;
|
||
|
||
x3 = x0 - i3 + self::$G43; // Offsets for fourth corner in (x,y,z,w) coords
|
||
y3 = y0 - j3 + self::$G43;
|
||
z3 = z0 - k3 + self::$G43;
|
||
w3 = w0 - l3 + self::$G43;
|
||
|
||
x4 = x0 + self::$G44; // Offsets for last corner in (x,y,z,w) coords
|
||
y4 = y0 + self::$G44;
|
||
z4 = z0 + self::$G44;
|
||
w4 = w0 + self::$G44;
|
||
|
||
// Work out the hashed gradient indices of the five simplex corners
|
||
ii = i & 255;
|
||
jj = j & 255;
|
||
kk = k & 255;
|
||
ll = l & 255;
|
||
|
||
gi0 = $this->perm[ii + $this->perm[jj + $this->perm[kk + $this->perm[ll]]]] % 32;
|
||
gi1 = $this->perm[ii + i1 + $this->perm[jj + j1 + $this->perm[kk + k1 + $this->perm[ll + l1]]]] % 32;
|
||
gi2 = $this->perm[ii + i2 + $this->perm[jj + j2 + $this->perm[kk + k2 + $this->perm[ll + l2]]]] % 32;
|
||
gi3 = $this->perm[ii + i3 + $this->perm[jj + j3 + $this->perm[kk + k3 + $this->perm[ll + l3]]]] % 32;
|
||
gi4 = $this->perm[ii + 1 + $this->perm[jj + 1 + $this->perm[kk + 1 + $this->perm[ll + 1]]]] % 32;
|
||
|
||
// Calculate the contribution from the five corners
|
||
t0 = 0.6 - x0 * x0 - y0 * y0 - z0 * z0 - w0 * w0;
|
||
if(t0 < 0){
|
||
n0 = 0.0;
|
||
}else{
|
||
t0 *= t0;
|
||
n0 = t0 * t0 * dot(grad4[gi0], x0, y0, z0, w0);
|
||
}
|
||
|
||
t1 = 0.6 - x1 * x1 - y1 * y1 - z1 * z1 - w1 * w1;
|
||
if(t1 < 0){
|
||
n1 = 0.0;
|
||
}else{
|
||
t1 *= t1;
|
||
n1 = t1 * t1 * dot(grad4[gi1], x1, y1, z1, w1);
|
||
}
|
||
|
||
t2 = 0.6 - x2 * x2 - y2 * y2 - z2 * z2 - w2 * w2;
|
||
if(t2 < 0){
|
||
n2 = 0.0;
|
||
}else{
|
||
t2 *= t2;
|
||
n2 = t2 * t2 * dot(grad4[gi2], x2, y2, z2, w2);
|
||
}
|
||
|
||
t3 = 0.6 - x3 * x3 - y3 * y3 - z3 * z3 - w3 * w3;
|
||
if(t3 < 0){
|
||
n3 = 0.0;
|
||
}else{
|
||
t3 *= t3;
|
||
n3 = t3 * t3 * dot(grad4[gi3], x3, y3, z3, w3);
|
||
}
|
||
|
||
t4 = 0.6 - x4 * x4 - y4 * y4 - z4 * z4 - w4 * w4;
|
||
if(t4 < 0){
|
||
n4 = 0.0;
|
||
}else{
|
||
t4 *= t4;
|
||
n4 = t4 * t4 * dot(grad4[gi4], x4, y4, z4, w4);
|
||
}
|
||
|
||
// Sum up and scale the result to cover the range [-1,1]
|
||
return 27.0 * (n0 + n1 + n2 + n3 + n4);
|
||
}*/
|
||
}
|