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import {colors} from './styles'
const GRADIENTS = [
[colors.pink3, colors.purple3],
[colors.purple3, colors.blue3],
[colors.blue3, colors.green3],
[colors.red3, colors.pink3],
]
export function getGradient(handle: string): string[] {
const gi = cyrb53(handle) % GRADIENTS.length
return GRADIENTS[gi]
}
// deterministic string->hash
// https://stackoverflow.com/a/52171480
function cyrb53(str: string, seed = 0): number {
let h1 = 0xdeadbeef ^ seed,
h2 = 0x41c6ce57 ^ seed
for (let i = 0, ch; i < str.length; i++) {
ch = str.charCodeAt(i)
h1 = Math.imul(h1 ^ ch, 2654435761)
h2 = Math.imul(h2 ^ ch, 1597334677)
}
h1 =
Math.imul(h1 ^ (h1 >>> 16), 2246822507) ^
Math.imul(h2 ^ (h2 >>> 13), 3266489909)
h2 =
Math.imul(h2 ^ (h2 >>> 16), 2246822507) ^
Math.imul(h1 ^ (h1 >>> 13), 3266489909)
return 4294967296 * (2097151 & h2) + (h1 >>> 0)
}
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