add generateSeedRandom Generator function to seedrandom and Add support for custom colors in rgba format

src/index.ts

@@ -1,8 +1,9 @@
 import { pick } from './utils/array'
 import { createBackground, createBlackout, createSvg } from './utils/svg'
-import { seedrandom } from './utils/random'
+import { generateSeedRandom } from './utils/random'
 import { avatarColors as aColors, backgroundColors as bColors } from './palette'
 import { Shape, faces, ears, muzzles, eyes, brows, patterns, hairs, emptyShape } from './shapes'
+import { convertIfRgbaColor } from './utils/colors'
 
 export type AvatarOptions = {
   size?: number;
@@ -22,7 +23,8 @@ const avatar = (
     round = true,
   }: AvatarOptions = {},
 ): string => {
-  const random = seedrandom(seed)
+  avatarColors = convertIfRgbaColor(avatarColors)
+  const random = generateSeedRandom(seed)
   const backgroundColor = pick(backgroundColors, random())
   const avatarColor = pick(avatarColors, random())
   const optional = (shapes: Shape[]) =>

src/palette/index.ts

@@ -14,3 +14,8 @@ export const avatarColors = [
   '#99c9bd',
   '#50c8c6',
 ]
+
+export const avatarColorsRGB = [
+  'rgba(255, 99, 71, 0.6)',
+  'rgba(122, 99, 71, 0.6)',
+]

src/utils/colors.ts

@@ -18,3 +18,28 @@ const rgb2Hex = (rgb: number[]) =>
 
 const clamp = (value: number, min: number, max: number) =>
   Math.min(max, Math.max(min, value))
+
+export const rgba2hex = (orig: string) => {
+  let a:string
+    const rgb = orig.replace(/\s/g, '').match(/^rgba?\((\d+),(\d+),(\d+),?([^,\s)]+)?/i),
+    alpha = (rgb && rgb[4] || '').trim(),
+      hex = rgb ?
+    (parseInt(rgb[1]) | 1 << 8).toString(16).slice(1) +
+    (parseInt(rgb[2]) | 1 << 8).toString(16).slice(1) +
+    (parseInt(rgb[3]) | 1 << 8).toString(16).slice(1) : orig
+
+  if (alpha !== '') {
+    a = alpha
+  } else {
+    a = '01'
+  }
+  // multiply before convert to HEX
+  a = ((parseInt(a) * 255) | 1 << 8).toString(16).slice(1)
+  const newHex = hex
+  return `#${newHex}`
+}
+
+const testIfRgba = (color: string)=> /^rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*(\d+(?:\.\d+)?))?\)$/.test(color)
+
+export const convertIfRgbaColor = (colors: string[]) =>
+  colors.map((color: string)=>testIfRgba(color) ? rgba2hex(color) : color)

src/utils/random.ts

@@ -1,7 +1,14 @@
-export const seedrandom = (seed: string) => {
+export function* seedrandom (seed: string) {
   let value = hash(seed)
   const nextValue = () => value = xorshift32(value)
-  return () => nextValue()
+  while(true){
+    yield nextValue()
+  }
+}
+
+export function generateSeedRandom (seed: string){
+  const seedRandomGen = seedrandom(seed)
+  return ()=>seedRandomGen.next().value ?? 0
 }
 
 const xorshift32 = (value: number) =>