--- /dev/null
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE document PUBLIC "-//APACHE//DTD Documentation V1.1//EN"
+ "http://cvs.apache.org/viewcvs.cgi/*checkout*/xml-forrest/src/resources/schema/dtd/document-v11.dtd">
+
+<!-- $Id$ -->
+
+<document>
+ <header>
+ <title>Layout managers</title>
+ <authors>
+ <person name="Peter B. West" email="pbwest@powerup.com.au"/>
+ </authors>
+ </header>
+ <body>
+ <section>
+ <title>Layout managers in FOP</title>
+ <p>
+ What do the layout managers do? Most layout is is "automatic"
+ in the sense of being a straightforward stacking operation.
+ Sibling inline-areas, including fo:character areas, are
+ stacked in line-areas in the inline-progression-direction.
+ Sibling block-areas, including line-areas, are stacked in the
+ block-progression-direction.
+ </p>
+ <p>
+ In the simple cases in which both the available
+ block-progression-dimension and the available
+ inline-progression-dimension are known, this process can be
+ driven bottom-up. Available dimensions trickle down from the
+ top, and the bottom level galleys can determine when their
+ available areas are full and suspend pending the arrival of
+ more areas. Such full notifications bubble back up the tree
+ of active galleys. E.g., if an inline galley fills a
+ line-area of a given inline-p-d and suspends while still
+ within the available block-p-d, the parent block-area galley
+ will simply stack the inline-area and notify the inline galley
+ to continue. If the inline-galley discovers that the next
+ line-area that it would generate will not fit in the the
+ block-p-d, it suspends with a notification to that effect to
+ its parent.
+ </p>
+ <p>
+ In more complex cases the dimensions may not be fully
+ specified, or decisions about layout may depend on later
+ layout. In all such cases some layout look-ahead is required
+ which can report results back to higher layout levels. The
+ job for a layout manager in these cirucmstances is to evaluate
+ the information flowing back and set parameters for the best
+ fit layout.
+ </p>
+ </section>
+ </body>
+</document>
projects / xmlgraphics-fop.git / commitdiff