A number of system attributes assists in the creation of posters.
PosterTemplate
$PosterTemplate, a string-type attribute, defines the template note to be used to render the poster.
PosterURL
$PosterURL, a URL-type attribute specifies a URL to be displayed in the poster. The developer's expectation (assumption) is that $PosterURL will be much less common that $PosterTemplate. This is reflected in the scenario whereby if a note has values for both $PosterTemplates and $PosterURL, the $PosterURL is ignored in favour of $PosterTemplate.
PosterCSS
$PosterCSS, a string, contains additional style rules that will be applied to a poster. $PosterCSS is used for supplying actual rules. This can be useful when restyling a web site's content for use as a poster.
PosterX, PosterY, PosterLabels, and PosterSettings
$PosterX, $PosterY, and $PosterLabels are list-type attributes whilst $PosterSettings is a string-type attribute. Any/all of these may be useful for passing information into a visualisation tool, depending on the needs/complexity of the tool in use. As with sandbox attributes like $MyList, these attributes have no special significance to Tinderbox.
$PosterX and $PosterY will typically be used to supply a list of X and Y values for a poster. However, not all posters need X/Y values and posters can use these attributes for whatever purposed they choose as with the other two. Tinderbox simply uses these four attributes' data as provided by the user's code.
PosterZoom
$PosterZoom is a numeric attribute representing the magnification applied to posters loaded through $PosterURL (but not those created via $PosterTemplate). Its default value is 1.0, representing the page’s normal size. A $PosterZoom of 0.5 would display the page at half size.
ScreenWidth and ScreenHeight
$ScreenWidth and $ScreenHeight are read-only attributes that reflect the pixel width and height of the poster at the current view magnification. Knowing these values can be useful for fine-tuning inputs to set the size of the (poster) visualisation, if it allows such an option.