space-before
and space-after
.
In the first example we increase the value of space-before.optimum
and space-after.optimum
between rules (marked by red)
from 1 to 10 points. We set conditionality
to "discard"
and precedence
to
"force"
. It means that space between rules must
be retained and not merged.
In the second example (marked by silver),
we try to set precedence
property to an integer-specifier.
So, the space after a rule must be merged with the
space preceding next rule in accordance with space-merging rules described
in the formatting model. Values of space-before.optimum
and
space-after.optimum
properties equal to the corresponding
values in the previous example but in reverse order. We also set
conditionality
to "retain"
.
A figure on the next page (I called it "hourglass") shows
examples of space-before(after).minimum
and
space-before(after).maximum
attributes. We set
the values of these properties to 0 and 20 points. Value of
space-before(after).optimum
changes progressively
from 12 points to 0 and back again by 0.5 pt steps.