issues with rotationAmountProperty

[pixelzoom]

Related to code review #259.

WaveScreenModel defines rotationRange and rotationAmountProperty like this:

 const rotationRange = new Range( 0, 1 );

// @public - amount the 3d view is rotated. 0 means top view, 1 means side view.
this.rotationAmountProperty = new NumberProperty( 0, {
  range: rotationRange
} );

Besides the fact that something named "rotation amount" should be something like a rotation angle, not some magic constants... This leads to code smell elsewhere. There are numerous places where the magic 0 and 1 are interpreted (sometimes to 1 decimal place, for some reason).

WaveScreenModel:

264 rotationAmount => rotationAmount !== rotationRange.min && rotationAmount !== rotationRange.max );
...
320 this.rotationAmountProperty.value = Util.clamp( this.rotationAmountProperty.value + wallDT * sign * 1.4, 0, 1 );

WaveScreenView:

384     waterSideViewNode.visible = rotationAmount === 1.0 && scene === model.waterScene;
385     waterGrayBackground.visible = rotationAmount !== 0 && scene === model.waterScene;

WaterDropLayer:

76 const fullyRotated = model.rotationAmountProperty.value === 1.0;

WaveMeterNode:

101 if ( model.rotationAmountProperty.value !== 0 && model.sceneProperty.value === model.waterScene ) {

And my personal favorite, Perspective3DNode:

117 const rotationAmount = Easing.CUBIC_IN_OUT.value( this.rotationAmountProperty.get() );

I think you'd be way better off if you:

(1) rename ViewType to ViewpointEnum, with values TOP and SIDE

(2) ditch rotationRange and rotationAmountProperty

(3) define viewpointProperty in WaveScreenModel:

this.viewpointProperty = new Property( ViewpointEnum.TOP, {
  validValues: ViewpointEnum.VALUE
} );

Then made changed your logic to make decisions based on whether viewpointProperty.value is TOP or SIDE. E.g. in WaveScreenView:

WaveScreenView:

384     waterSideViewNode.visible = ( viewpointProperty.value === ViewpointEnum.SIDE && scene === model.waterScene );
385     waterGrayBackground.visible = ( viewpointProperty.value === ViewpointEnum.SIDE && scene === model.waterScene );

[pixelzoom]

Ah... so in WaveScreenModel:

this.rotationAmountProperty.value = Util.clamp( this.rotationAmountProperty.value + wallDT * sign * 1.4, 0, 1 );

So 0 and 1 are not the only values, it does range continuously between 0 and 1, presumably to rotate between top and side views.

Then I'm not sure what to do here. It sure is confusing, and it's probably because of the rotatationRange and rotationAmountProperty names.

[pixelzoom]

This was addressed by @samreid in REVIEW comments. We stuck with rotationAmountProperty with the same semantics. rotationRange was changed to rotationAmountRange.

Closing.