[Inkscape-devel] path from "style" to name of href and image contents?

24 Aug 2012


      Sorry to be dense but I still have not found an easy way to locate this 
sort of information, and I end
up wandering around in circles every time I venture into the source 
code looking for it.
There are three kinds of fills that have to go through a print method:  
paint, pattern, and image.  The first
is already handled and can be detected with isColor().  The information 
needed for the other two are somewhere
a hop skip and a jump down from "style".  In the svg these are in 
<defs> like this:
<pattern
        y="0"
        x="0"
        height="6"
        width="6"
        patternUnits="userSpaceOnUse"
        id="EMFhatch0_3F7FFF">
       <path
          id="path3933"
          style="fill:none;stroke:#3F7FFF"
          d="M 0 0 6 0" />
     </pattern>
and
<pattern
        height="4"
        width="4"
        y="0"
        x="0"
        patternUnits="userSpaceOnUse"
        id="EMFimage1">
       <image
          id="image3992"
          height="4"
          width="4"
          y="0"
          x="0"
xlink:href="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAAECAIAAAAmkwkpAAAAFUlEQVQImWMMDQ1lgAEmBiTAglMGAEruAgjcYZR9AAAAAElFTkSuQmCC" 
/>
     </pattern>
In the print driver "style" is the only link to this information.  
Presumably the path starts out with style->fill.value.href->getObject(). 
Where does one go from there?
All I need is:
1.  The type of the object for the fill (pattern or image).
2.  For a pattern, the name of the object (the part that corresponds to 
"EMFimage1" and "EMFhatch0_3F7FFF" above).
3.  For the image case, the width, height, and bitmap.  The bitmap can 
be either an RGB array or
the png string as in the SVG.
What incantations are need to pull these values out???
Thank you,
David Mathog
mathog@...1176...
Manager, Sequence Analysis Facility, Biology Division, Caltech