Better noise than stripes :D

src/Controllers/EnvironmentController.js

@@ -5,6 +5,7 @@ const CellStates = require("../Organism/Cell/CellStates");
 const Neighbors = require("../Grid/Neighbors");
 const FossilRecord = require("../Stats/FossilRecord");
 const Hyperparams = require("../Hyperparameters");
+const Perlin = require("../Utils/Perlin");
 
 class EnvironmentController extends CanvasController{
     constructor(env, canvas) {
@@ -55,20 +56,20 @@ class EnvironmentController extends CanvasController{
     Iterate over grid from 0,0 to env.num_cols,env.num_rows and create random walls using perlin noise to create a more organic shape.
     */
     randomizeWalls(thickness=1) {
-        var noise_scale = 0.05;
-        var noise_offset = 0.5;
         var noise_threshold = 0.5;
-        var noise_multiplier = 0.5;
-        var noise_offset_x = this.env.num_cols/2;
-        var noise_offset_y = this.env.num_rows/2;
+        var avg_noise = 0;
+
         for (var r = 0; r < this.env.num_rows; r++) {
             for (var c = 0; c < this.env.num_cols; c++) {
-                var noise = noise_multiplier * noise_offset + noise_scale * noise_offset * Math.sin(noise_scale * (c + noise_offset_x) + noise_scale * (r + noise_offset_y));
+                var noise = Perlin.get(c, r);
+                avg_noise += noise/(this.env.num_rows*this.env.num_cols);
                 if (noise > noise_threshold && noise < noise_threshold + thickness/10) {
                     this.dropCellType(c, r, CellStates.wall, true);
                 }
             }
         }
+
+        console.log("Average noise: " + avg_noise);
     }
 
     updateMouseLocation(offsetX, offsetY){

src/Utils/Perlin.js

@@ -0,0 +1,46 @@
+let perlin = {
+    rand_vect: function(){
+        let theta = Math.random() * 2 * Math.PI;
+        return {x: Math.cos(theta), y: Math.sin(theta)};
+    },
+    dot_prod_grid: function(x, y, vx, vy){
+        let g_vect;
+        let d_vect = {x: x - vx, y: y - vy};
+        if (this.gradients[[vx,vy]]){
+            g_vect = this.gradients[[vx,vy]];
+        } else {
+            g_vect = this.rand_vect();
+            this.gradients[[vx, vy]] = g_vect;
+        }
+        return d_vect.x * g_vect.x + d_vect.y * g_vect.y;
+    },
+    smootherstep: function(x){
+        return 6*x**5 - 15*x**4 + 10*x**3;
+    },
+    interp: function(x, a, b){
+        return a + this.smootherstep(x) * (b-a);
+    },
+    seed: function(){
+        this.gradients = {};
+        this.memory = {};
+    },
+    get: function(x, y) {
+        if (this.memory.hasOwnProperty([x,y]))
+            return this.memory[[x,y]];
+        let xf = Math.floor(x);
+        let yf = Math.floor(y);
+        //interpolate
+        let tl = this.dot_prod_grid(x, y, xf,   yf);
+        let tr = this.dot_prod_grid(x, y, xf+1, yf);
+        let bl = this.dot_prod_grid(x, y, xf,   yf+1);
+        let br = this.dot_prod_grid(x, y, xf+1, yf+1);
+        let xt = this.interp(x-xf, tl, tr);
+        let xb = this.interp(x-xf, bl, br);
+        let v = this.interp(y-yf, xt, xb);
+        this.memory[[x,y]] = v;
+        return v;
+    }
+}
+perlin.seed();
+
+module.exports = perlin;