three.js/examples/jsm/renderers/nodes/consts/MathConsts.js

import ConstNode from '../core/ConstNode.js';

export const PI = new ConstNode( '3.141592653589793', 'float', 'PI' );
export const RECIPROCAL_PI = new ConstNode( '0.3183098861837907', 'float', 'RECIPROCAL_PI' );