/**
* ===========================================
* LibLayout : a free Java layouting library
* ===========================================
*
* Project Info: http://reporting.pentaho.org/liblayout/
*
* (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
*
* This library is free software; you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Foundation;
* either version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ------------
* $Id: FillPhysicalPagesStep.java 6653 2008-12-02 14:53:40Z tmorgner $
* ------------
* (C) Copyright 2006-2007, by Pentaho Corporation.
*/
package org.jfree.layouting.renderer.process;
import org.jfree.layouting.renderer.model.PageAreaRenderBox;
import org.jfree.layouting.renderer.model.ParagraphRenderBox;
import org.jfree.layouting.renderer.model.RenderBox;
import org.jfree.layouting.renderer.model.RenderNode;
import org.jfree.layouting.renderer.model.page.LogicalPageBox;
/**
* This Step copies all content from the logical page into the page-grid. When
* done, it clears the content and replaces the elements with dummy-nodes. These
* nodes have a fixed-size (the last known layouted size), and will not be
* recomputed later.
* <p/>
* Adjoining dummy-nodes get unified into a single node, thus simplifying and
* pruning the document tree.
*
* @author Thomas Morgner
*/
public class FillPhysicalPagesStep extends IterateVisualProcessStep
{
private long contentEnd;
private long contentStart;
public FillPhysicalPagesStep()
{
}
public LogicalPageBox compute(final LogicalPageBox pagebox,
final long pageStart,
final long pageEnd)
{
this.contentStart = pagebox.getHeaderArea().getHeight();
this.contentEnd = (pageEnd - pageStart) + contentStart;
// This is a simpel strategy.
// Copy and relocate, then prune. (I whished we could prune first, but
// this does not work.)
//
// For the sake of efficiency, we do *not* create private copies for each
// phyiscal page. This would be an total overkill.
final LogicalPageBox derived = (LogicalPageBox) pagebox.derive(true);
// first, shift the normal-flow content downwards.
// The start of the logical pagebox might be in the negative range now
// The header-size has already been taken into account by the pagination
// step.
final BoxShifter boxShifter = new BoxShifter();
boxShifter.shiftBoxUnchecked(derived, -pageStart + contentStart);
// now remove all the content that will not be visible at all ..
if (startBlockLevelBox(derived))
{
// not processing the header and footer area: they are 'out-of-context' bands
processBoxChilds(derived);
}
finishBlockLevelBox(derived);
// Then add the header at the top - it starts at (0,0) and thus it is
// ok to leave it unshifted.
// finally, move the footer at the bottom (to the page's bottom, please!)
final PageAreaRenderBox footerArea = derived.getFooterArea();
final long footerPosition = pagebox.getPageHeight() -
(footerArea.getY() + footerArea.getHeight());
final long footerShift = footerPosition - footerArea.getY();
boxShifter.shiftBoxUnchecked(footerArea, footerShift);
// the renderer is responsible for painting the page-header and footer ..
return derived;
}
protected void processParagraphChilds(final ParagraphRenderBox box)
{
processBoxChilds(box);
}
/**
* Invisible nodes may need special treatment here.
*
* @param box
* @return
*/
protected boolean startBlockLevelBox(final RenderBox box)
{
RenderNode node = box.getFirstChild();
while (node != null)
{
if (node.isIgnorableForRendering())
{
node = node.getNext();
}
if ((node.getY() + node.getHeight()) <= contentStart)
{
final RenderNode next = node.getNext();
box.remove(node);
node = next;
}
else if (node.getY() >= contentEnd)
{
final RenderNode next = node.getNext();
box.remove(node);
node = next;
}
else
{
node = node.getNext();
}
}
return true;
}
}