Table 143 – Variables used in the page group compositing formulas

Variable

Meaning

P

The page group, consisting of all elements E 1 , … , E n in the page’s top-level stack

Cg

Computed colour of the page group

fg

Computed shape of the page group

g

Computed alpha of the page group

C

Computed colour of the page

W

Initial colour of the page (nominally white but may vary depending on the properties of the medium or the needs of the application)

U

An undefined colour (which is not used, since the 0 argument of Composite is 0)