Re: DOCBOOK-APPS: Is bottom baseline alignment of inlinemediaobjectpossible ?

[Bob Stayton <bobs at caldera dot com>]

On Sun, Dec 01, 2002 at 05:18:28PM -0600, Paul Grosso wrote:
> At 21:32 2002 11 28 -0800, Bob Stayton wrote:
> >On Thu, Nov 28, 2002 at 12:36:35PM +0100, Alain NAKACHE wrote:
> >> . . .
> >> and here is a schema of the result with XLST 1.57.0 + FOP 0.24 :
> >> 
> >> . +-+  Blahhhh, Blahhh, Blahhh, Blahhh, Blahhh,
> >>    | |
> >>    +-+
> >>    Blahhh, ....
> >> . +-+ Blahhhh, Blahhh, Blahhh, Blahhh, Blahhh,
> >>    | |
> >>    +-+
> >>    Blahhh, ....
> >> 
> >> With DSSSL + JadeTex i obtained this result :
> >> 
> >>    +-+
> >>    | |
> >> . +-+  Blahhhh, Blahhh, Blahhh, Blahhh, Blahhh,
> >>    Blahhh, ....
> >>    +-+
> >>    | |
> >> . +-+  Blahhhh, Blahhh, Blahhh, Blahhh, Blahhh,
> >>    Blahhh, ....
> >> 
> >> Is it possible to obtain the same result as DSSSL rendering with XSLT ?
> >
> >Yes, but not with FOP it seems.  The default alignment for
> >XSL-FO is for the bottom of the graphics block to be on the
> >baseline of the text, as your DSSSL example produces.  The
> >DocBook XSL stylesheets are putting out the correct XSL-FO,
> >but FOP isn't getting it right.  When I process the same
> >file with RenderX's XEP, I get the correct baseline
> >alignment that you want.
> 
> 
> When I run Alain's source through XSLT (using the 1.50 stylesheets),
> I get the following for the first fo:list-item (with various irrelevant
> properties elided and the results pretty-printed):
> 
> <fo:list-item>
>   <fo:list-item-label end-indent="label-end()">
>     <fo:block>&#x2022;</fo:block>
>   </fo:list-item-label>
>   <fo:list-item-body start-indent="body-start()">
>     <fo:block>
>       <fo:external-graphic src="url(...)"/>Blahhhh, Blahhh, Blahhh, Blahhh, 
>       Blahhh, Blahhh, ....   
>     </fo:block>
>   </fo:list-item-body>
> </fo:list-item>
> 
> I agree that the list-item-body should look as you two say it should,
> but I'm missing why the result shouldn't look more like:
> 
> . +-+
>   | |
>   +-+  Blahhhh, Blahhh, Blahhh, Blahhh, Blahhh,
>   Blahhh, ....
> 
> with the list-item-label (the bullet) aligning nearer the top of the graphic.
> 
> 6.8.3 fo:list-item says [1]:
> 
>   The children of each normal area returned by an fo:list-item
>   formatting object returned by the fo:list-item-label and fo:list-item-body
>   objects are positioned in the block-progression-direction with respect to
>   each other according to the relative-align trait.
> 
> and 7.13.6 "relative-align" [2] indicates that the initial value
> for relative-align is before which means:
> 
>   the before-edge of the first area descendant generated by the
>   fo:list-item-label is placed coincident with the before-edge of
>   the area generated by the fo:list-item.  Similarly the before-edge
>   of the first area descendant generated by the fo:list-item-body is
>   placed coincident with the before-edge of the area generated by the
>   fo:list-item. 
> 
> Assuming a line-stacking-strategy of max-height (which is the default),
> doesn't that all mean that the result should have the bullet aligned
> nearer the top of the graphic?
> 
> paul
> 
> [1] http://www.w3.org/TR/xsl/slice6.html#fo_list-item
> [2] http://www.w3.org/TR/xsl/slice7.html#relative-align
> 


Ah, I didn't notice the bullet location.
Yes, you are correct that it should appear at the top
with this FO input.  In XEP output, the bullet is at the top.
I tried setting relative-align="baseline", but
neither FOP nor XEP support that property value yet
(FOP omits it from its supported property list, and XEP
admits that it does not).

-- 

Bob Stayton                                 400 Encinal Street
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