random colors now being sampled from hsluv (#80)

This samples colors from the HSLUV color space instead of the RGB color space, which should result in better randomized colors.

desc.d.ts

@@ -0,0 +1 @@
+declare module "colorspaces"

lib/random-colors.ts

@@ -1,5 +1,6 @@
 import { Random } from "./random";
 import { range } from "./util";
+import * as colorspaces from 'colorspaces';
 
 /**
  * Clamp the given number to be between 0 and 255, then
@@ -19,8 +20,38 @@ export function clampedByteToHex(value: number): string {
 }
 
 function createRandomColor(rng: Random): string {
-  const rgb = range(3).map(() => rng.inRange({ min: 0, max: 255, step: 1 }));
-  return "#" + rgb.map(clampedByteToHex).join("");
+    const max_luv_samples = 100;
+    let luv_sample_failed = true;
+    let rand_color_hex:string = "#000000";
+
+    //See if we can pull out a sample inside the LUV solid
+    for (let i=0; i<max_luv_samples; i++) {
+	let L = rng.inRange({ min: 0, max: 100, step: 1 });
+	let u = rng.inRange({ min: -128, max: 128, step: 1 });
+	let v = rng.inRange({ min: -128, max: 128, step: 1 });
+	let rand_color = colorspaces.make_color('CIELUV', [L, u, v]);
+	
+	if(rand_color.is_displayable()) {
+	    rand_color_hex = rand_color.as('hex');
+	    luv_sample_failed = false;
+	    break;
+	}
+    }
+
+    //just sample sRGB if I couldn't sample a random LUV color
+    if(luv_sample_failed) {
+	console.log("Sampling sRGB")
+	let rgb = (new Array<number>(3)).map(() => rng.inRange({ min: 0, max: 255, step: 1 }));
+	console.log(rgb)
+	for(let i=0; i<rgb.length; i++) {
+	    rgb[i] = rgb[i]/255.0;
+	}
+	console.log(rgb)
+	let rand_color = colorspaces.make_color('sRGB',rgb);
+	rand_color_hex = rand_color.as('hex');
+    }
+
+    return rand_color_hex;
 }
 
 /**

package-lock.json

@@ -2834,6 +2834,11 @@
       "resolved": "https://registry.npmjs.org/colorette/-/colorette-1.2.1.tgz",
       "integrity": "sha512-puCDz0CzydiSYOrnXpz/PKd69zRrribezjtE9yd4zvytoRc8+RY/KJPvtPFKZS3E3wP6neGyMe0vOTlHO5L3Pw=="
     },
+    "colorspaces": {
+      "version": "0.1.5",
+      "resolved": "https://registry.npmjs.org/colorspaces/-/colorspaces-0.1.5.tgz",
+      "integrity": "sha1-elqa71MGmN4IkJ2F7QAAf/jDHvk="
+    },
     "combined-stream": {
       "version": "1.0.8",
       "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.8.tgz",

package.json

@@ -26,6 +26,7 @@
     "babel-jest": "^26.6.3",
     "cheerio": "^1.0.0-rc.5",
     "classnames": "^2.3.1",
+    "colorspaces": "^0.1.5",
     "gh-pages": "^3.1.0",
     "jest": "^26.6.3",
     "parcel-bundler": "^1.12.4",