I am having difficulty understanding how the dual column layout is implemented in FOP.
Scenario 1: I set the property column-count="2" on my fo:region-body object. As such the text appears in dual column format. If I have the page totally filled out, then everything seems to be fine. But if my document does not contain enough text (usually the last page in my document), the text does not seem to be evenly distributed in both the columns. It first tries to fill the left column and then tries to fill the right column if there is an additional text.
As mandated by the spec.
If this page is the last page and we don't have any additional text, the renderer should try to distribute it evenly on both columns. That is the behavior I have seem on other viewers.
This can be forced by adding an empty block with span="all" at the end of the flow.
Scenario 2: If I keep switching between dual and single columns on the same page ( using the span="all" property on an fo:block within a page), the distribution between the columns seems to be happening but does not happen accurately. I see more text on the left hand column than on the right hand column. Doing this would leave additional blank space on the right hand column before we switch to single column layout.
This is due to a simple algorithm for balancing. Getting column balancing even somewhat right is quite complicated.
J.Pietschmann
