# Perlin Noise

(Difference between revisions)

## Description

The following snippet shows how to use noise for smoothly randomly moving objects, rotating them or animated light intensity.

## Usage

Download the package. Open Unity with your own project folder. Double click on the unityPackage in the finder. [PerlinNoise]

This installs the perlin noise class and 3 scripts implementing:

1. Animated light intensity noise
2. Animated noise position
3. Animated noise rotation

To use one of the scripts, just drag them on a game object, to make them move, rotate, animate light based on noise.

## Another function

previous information above is out of date links here are 4 new functions including voronoi on a pretty free license UnityScript noises on forum Here is a nearly complete implementation of Perlin noise in UnityScript,although I didn't finish completing it because I didn't understand JavaScript this.noise function. I am sure I will finish it or else you can help if you want the original is here- JavaScript Perlin noise implementation

```#pragma strict

// This is a port of Ken Perlin's Java code. The
// original Java code is at http://cs.nyu.edu/%7Eperlin/noise/.
// Note that in this version, a number from 0 to 1 is returned.
function PerlinNoise() {
var x :int;
var y :int;
var z :int;
var t :int;
var a :int;
var b :int;
var n :int;
var hash :int;
thisnoise (x, y, z);
lerp( t, a, b);
scale(n);}

function thisnoise (x:int, y:int, z:int) {

var p : int[]; //array
p = new int[512];
var permutation : int[] = [ 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
];
for (var i=0; i < 256 ; i++)
p[256+i] = p[i] = permutation[i];

var X = parseInt(Mathf.Floor(x)) & 255;                  // FIND UNIT CUBE THAT
var Y = parseInt(Mathf.Floor(y)) & 255;                // CONTAINS POINT.
var Z = parseInt(Mathf.Floor(z)) & 255;
x -= Mathf.Floor(x);                                // FIND RELATIVE X,Y,Z
y -= Mathf.Floor(y);                                // OF POINT IN CUBE.
z -= Mathf.Floor(z);
var      v = fade(y);                               // FOR EACH OF X,Y,Z.
var A = p[X  ]+Y;var AA = p[A]+Z;var AB = p[A+1]+Z;      // HASH COORDINATES OF
var B = p[X+1]+Y;var BA = p[B]+Z;var BB = p[B+1]+Z;      // THE 8 CUBE CORNERS,

return scale(lerp(w, lerp(v, lerp(u, grad(p[AA  ], x  , y  , z   ),  // AND ADD
grad(p[BA  ], x-1, y  , z   )), // BLENDED
lerp(u, grad(p[AB  ], x  , y-1, z   ),  // RESULTS
grad(p[BB  ], x-1, y-1, z   ))),// FROM  8
lerp(v, lerp(u, grad(p[AA+1], x  , y  , z-1 ),  // CORNERS
grad(p[BA+1], x-1, y  , z-1 )), // OF CUBE
lerp(u, grad(p[AB+1], x  , y-1, z-1 ),
}
function fade(t:int) { return t * t * t * (t * (t * 6 - 15) + 10); }
function lerp( t:int, a:int, b:int) { return a + t * (b - a); }
function grad(hash:int, x:int, y:int, z:int) {
var h = hash & 15;                      // CONVERT LO 4 BITS OF HASH CODE
var u = h<8 ? x : y;                 // INTO 12 GRADIENT DIRECTIONS.
var  v = h<4 ? y : h==12||h==14 ? x : z;
return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);
}
function scale(n:int) { return (1 + n)/2; }```