Re: [docbook-apps] docbook + svg + epub3 -- how to do?

[Bob Stayton <bobs@sagehill.net>]

Regarding manually embedding <item> entries, you can automate that 
somewhat.   There is an empty placeholder template in the epub3 
stylesheet named 'user.manifest.items'.  If that template is customized 
to generate <item> elements in the correct namespace, then they are 
included in the .opf file inside the <manifest> element.

Bob Stayton
Sagehill Enterprises
bobs@sagehill.net

On 3/5/2014 12:47 PM, Robert Nagle wrote:
> Thanks, Bob for the clarification.
>
> The image I am trying to use consists of an svg file and an embedded jpg.
> I assume that if I manually made <item> entries for the 8 or 9 embedded
> .jpg  images inside the .opf file
> , it would still pass epubcheck. (Based on my reading of the recently
> revised Kindle Formatting Guide, it should render properly on Kindle
> devices and  I suspect, ibooks).
>
> Robert Nagle
>
>
> On Wed, Mar 5, 2014 at 11:44 AM, Bob Stayton <bobs@sagehill.net> wrote:
>
> > Hi Robert,
> > SVG is supported pretty well in the epub3 stylesheet.
> >
> > While you can put SVG code inside an imagedata element, most people keep
> > the SVG in a separate file and reference the file with a fileref attribute
> > on the imagedata.  If you use a fileref, the epub3 stylesheet will do the
> > following:
> >
> > 1.  Output an XHTML <img> element whose src attribute references the svg
> > filename.
> >
> > 2.  For each svg image found in the document, it will add an <item>
> > element to the .opf metadata file.
> >
> > 3.  It will add a properties="svg" attribute to the <item> element in the
> > .opf file for the XHTML output file containing the svg.
> >
> > As with other image files, the stylesheet will not copy the svg file to
> > the output directory.  Most people use a Makefile or Ant task for that
> > purpose.
> >
> > The stylesheet does not open any SVG code and investigate it for embedded
> > image files.
> >
> > There currently is no support for a fallback mechanism for browsers that
> > don't support svg.  In DocBook 5.1 (forthcoming), there will be support for
> > multiple imagedata elements inside an imageobject, which would allow you to
> > specify a backup image that the stylesheet could reference.
> >
> > Hope this helps.
> >
> > Bob Stayton
> > Sagehill Enterprises
> > bobs@sagehill.net
> >
> >
> > On 3/5/2014 2:17 AM, Robert Nagle wrote:
> >
> > > Hi, there, I am working on an ebook where I want to use svg for images. I
> > > see that SVG support in Kindle has improved recently, and plus my images
> > > might future-proof better if I use svg.
> > >
> > > I suspect that svg and docbook play well together.  But I don't know
> > > really
> > > what's going on.  I see that there's an example of svg inside an imagedata
> > > element here: http://docbook.org/tdg51/en/html/_any.svg.html
> > >
> > > How would the epub3 stylesheets render the example (generally I mean).
> > > Does
> > > it just pass the svg code as is  into the xhtml?
> > >
> > > Is there any way to do a fallback rendering if the browser or tablet
> > > doesn't support svg?
> > >
> > > Also, if I use the example below as my svg, when you run the epub3 XSLT,
> > > which of these files (if any) will appear in package.opf file?
> > >
> > > Robert Nagle
> > >
> > >
> > > <svg id="ch1-title-image" viewBox="0 0 1000 500"
> > > preserveAspectRatio="xMidYMin meet">
> > >      <defs>
> > >         <desc>
> > >             Chapter 1
> > >         </desc>
> > >         <clipPath id="inset-ch1">
> > >             <use xlink:href="images/ChapterBorder.svg#inset-border"/>
> > >         </clipPath>
> > >      <defs>
> > >
> > >      <image xlink:href="images/Ch1.jpeg"
> > >             x="350" y="100" width="300" height="200"
> > >             clip-path = "url(#inset-ch1)" />
> > >
> > >      <use xlink:href="images/ChapterBorder.svg"
> > >            x="0" y="0" width="1000" height="500" />
> > >
> > >      <text x="500" y="400" text-anchor="middle" font-size="60">
> > >          The Lamp in the Window
> > >      </text>
> > > </svg>