Section 5.3.2 of the spec is really hard to understand. I combine it
with 5.1.4 about Inheritance. Then my guess is this:
<fo:block margin-left="1pc">A test file
<fo:inline-container start-indent="1.5pc">
<fo:block margin-left="1pc">A test file</fo:block>
</fo:inline-container>
</fo:block>
The computed value of start-indent on the outer block is 'start-indent
= inherited_value_of(start-indent) + margin-corresponding +
padding-corresponding + border-corresponding-width' = 0 + 1pc + 0 +
0. The computed value of start-indent on the inner block is
'start-indent = inherited_value_of(start-indent) +
margin-corresponding + padding-corresponding +
border-corresponding-width' = 1.5pc + 1pc + 0 + 0.
In this case:
<fo:block margin-left="1pc">A test file
<fo:inline-container>
<fo:block margin-left="1pc">A test file</fo:block>
</fo:inline-container>
</fo:block>
the computed value of start-indent on the outer block is 'start-indent
= inherited_value_of(start-indent) + margin-corresponding +
padding-corresponding + border-corresponding-width' = 0 + 1pc + 0 +
0. The computed value of start-indent on the inner block is
'start-indent = inherited_value_of(start-indent) +
margin-corresponding + padding-corresponding +
border-corresponding-width' = 1pc + 1pc + 0 + 0. The inherited value
uses the calculated value (sect. 5.1.4). That is the value that should
be returned by
pList.getParentPropertyList().get(Constants.PR_START_INDENT).getLength().
The inherited value should not be stored, but used in the computation
of the property value. This should be implemented by the property
maker.
When I run the above examples in a debugger, I find that the computed
start-indent values CommonMarginBlock.startIndent are exactly like I
argue above they should be. There does not seem to be a need to add
the inherited value later; the property maker already has done so. See
IndentPropertyMaker.compute(PropertyList). It uses
propertyList.getInherited(baseMaker.propId).getNumeric()) to get the
inherited value. Earlier FOP developers understood this part well.
If you find wrong results, then the problem must be elsewhere.
Is there a book or treatise on these subjects, where we can read how a
knowledgeable author interprets these difficult parts of the spec?
Regards, Simon
On Fri, Jan 07, 2005 at 09:26:15AM +0100, Jeremias Maerki wrote:
> Finn or Simon,
>
> would you please check if it is acceptable to put the inherited values
> directly into the CommonMarginBlock? It might have been cleaner to
> always get the value via the parent FO but I think in this case it helps
> simplifying the code in TraitSetter and BlockLayoutManager.
>
> On 07.01.2005 09:21:21 jeremias wrote:
> > jeremias 2005/01/07 00:21:21
> >
> > Modified: src/java/org/apache/fop/fo/properties CommonMarginBlock.java
> > src/java/org/apache/fop/layoutmgr TraitSetter.java
> > BlockLayoutManager.java
> > Log:
> > Bugfix for start-indent calculation for nested blocks. The inherited
> > start-indent wasn't taken into account as described in 5.3.2 of the spec.
> > Minor style and javadoc improvements on the way.
>
> <snip/>
>
> > Revision Changes Path
> > 1.5 +34 -2
> > xml-fop/src/java/org/apache/fop/fo/properties/CommonMarginBlock.java
> >
> > Index: CommonMarginBlock.java
> > ===================================================================
> > RCS file:
> > /home/cvs/xml-fop/src/java/org/apache/fop/fo/properties/CommonMarginBlock.java,v
> > retrieving revision 1.4
> > retrieving revision 1.5
> > diff -u -r1.4 -r1.5
> > --- CommonMarginBlock.java 28 Oct 2004 10:00:24 -0000 1.4
> > +++ CommonMarginBlock.java 7 Jan 2005 08:21:21 -0000 1.5
> > @@ -1,5 +1,5 @@
> > /*
> > - * Copyright 1999-2004 The Apache Software Foundation.
> > + * Copyright 1999-2005 The Apache Software Foundation.
> > *
> > * Licensed under the Apache License, Version 2.0 (the "License");
> > * you may not use this file except in compliance with the License.
> > @@ -70,6 +70,16 @@
> > public Length endIndent;
> >
> > /**
> > + * The inherited "start-indent" property.
> > + */
> > + public Length inheritedStartIndent;
> > +
> > + /**
> > + * The inherited "end-indent" property.
> > + */
> > + public Length inheritedEndIndent;
> > +
> > + /**
> > * Create a CommonMarginBlock object.
> > * @param pList The PropertyList with propery values.
> > */
> > @@ -84,5 +94,27 @@
> >
> > startIndent = pList.get(Constants.PR_START_INDENT).getLength();
> > endIndent = pList.get(Constants.PR_END_INDENT).getLength();
> > +
> > + if (!pList.getFObj().generatesReferenceAreas()) {
> > + inheritedStartIndent = pList.getParentPropertyList()
> > + .get(Constants.PR_START_INDENT).getLength();
> > + inheritedEndIndent = pList.getParentPropertyList()
> > + .get(Constants.PR_END_INDENT).getLength();
> > + }
> > + }
>
> <snip/>
>
>
>
> Jeremias Maerki
>
--
Simon Pepping
home page: http://www.leverkruid.nl
