@polygonjs/polygonjs/dist/src/core/geometry/util/MeshInverse.js

node-based WebGL 3D engine https://polygonjs.com

"use strict";
export function meshInverse(mesh) {
  const index = mesh.geometry.getIndex();
  if (!index) {
    return;
  }
  const facesCount = index.count / 3;
  const array = index.array;
  for (let i = 0; i < facesCount; i++) {
    const a = array[i * 3];
    const b = array[i * 3 + 1];
    const c = array[i * 3 + 2];
    array[i * 3] = c;
    array[i * 3 + 1] = b;
    array[i * 3 + 2] = a;
  }
}