.color = new Float32Array(cube.position.length / 3 * 4);
    cube.color.forEach((v, i) => {
      const ch = i % 4;
      cube.color[i] = ch === 3
          ? 1
          : srcNormals[ii + ch] * 0.5 + 0.5;
    });
    const target = srcNormals.slice(ii, ii + 3);
    const self = [0, 0, 0];
    const up = Math.abs(target[1]) === 1 ? [1, 0, 0] : [0, 1, 0];
    const lookAt = m4.lookAt(self, target, up);
    let mat = m4.identity();
    mat = m4.translate(mat, srcPositions.slice(ii, ii + 3));
    mat = m4.mult