Change the camera.up to (0, 0, 1), the examples webgl_shaders_ocean not work rightly

Questions
,
1

Hi, anyone can help me for this problem?

If I change the camera up to (0,0,1), this examples three.js examples can not work rightly, even if i change some codes:

// comment this line
// water.rotation.x = - Math.PI / 2;

...
// add this line
skyUniforms[ 'up' ].value = new THREE.Vector3(0, 0, 1);

the result is not right, can anybody help me ?