[SOLVED] How can I scale entity unidirectionally?

When scaling an entity, it scale bidirectionally.

How to scale entity unidirectionally? Just like the webvr demo on WebVR Demo - PLAYCANVAS .

I’ve check the code, the core lines are:

Box.prototype.onSelectionProgress = function (progress) {
    // Scale the bar based on the progress
    this.loadingBar.setLocalScale(progress, 1, 1);

That’s should be scale unidirectionally, but the result is unidirectional. Why ?