BillBoard works on a different principle to ViewportText. It is targeted primarily at running text and will scale the content by justifying and scaling at the same time. ViewportText, on the other hand, makes no attempt at justification.
BillBoard has a couple of interesting features: If text is entered without returns, Billboard checks the settings for Min Chars / Line and breaks the text accordingly, at the same time observing the settings for Font Ratio (the amount of scaling applied) and Max Font Size.
If text is entered with returns, BillBoard can scale single words or groups of words to fit the maximum width of the container. The result is an interesting placard effect.
Further effects are a Font Delay setting – the time it takes for the text to appear on page load can be delayed by up to 500 milliseconds – and a Fade In time, which can be set up to 10,000 milliseconds.
BillBoard will either use the theme fonts for its content, or can be set to use Google, or local fonts. Depending on the Google or local fonts used, the line spacing may overlap. To compensate in such a case, the Line Spacing may be corrected. The standard (recommended) setting is 0.9.
Setting your font’s colour with RapidWeaver’s standard editing tools can lead to chaotically overlapping letter and line spacing. The HUD, however, has a Style setting that will allow you to override the theme’s settings for font colour and link effects. The font Size may also be set, but has no effect when BillBoard is set to Automatic. The Text Opacity may be altered. This is especially useful for enhancing legibility when BillBoard is positioned over of an image.
Tastes differ and lead to diversity. I personally am an advocate of clean Typography. Used thoughtfully, however, BillBoard is a great stack. An ideal scenario, for instance, would be a heading with fully justified subheading.
Oh, and to date all BWD Stacks are free!