function coordinates(flatCoordinates, offset, end, stride) {
  while (offset < end - stride) {
    for (let i = 0; i < stride; ++i) {
      const tmp = flatCoordinates[offset + i];
      flatCoordinates[offset + i] = flatCoordinates[end - stride + i];
      flatCoordinates[end - stride + i] = tmp;
    }
    offset += stride;
    end -= stride;
  }
}
@param {Array<number>} flatCoordinates Flat coordinates.
@param {number} offset Offset.
@param {number} end End.
@param {number} stride Stride.