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However, the project was abandoned after the pattern section due to both time constraints and some lack of interest. After the release of Inkscape 0.46, some of what is discussed in this tome is already obsolete.
Nevertheless, it should make for an interesting read, as this is one of the rare pieces of literature that C-chan published within his forum (wall-o-text posts notwithstanding).
For the source, you can access a special Tutorials folder located here: [link]
It not only contains the source for this Inkscape tutorial, but it also contains source art for some of the examples used in the tutorial, as well as other random tutorials from his forum era.
What an odd question... cel-shading in Inkscape is perhaps the easiest thing to do as far as proper-shading is concerned.
True, gradients are built into the base path, but don't look natural IMHO... I really truly only use gradients in rare instances where the colour shift can be gradual and well-disguised. ^^
In order to imitate cel-shading, you simply need to superimpose one solid (or semi-transparent) path over another solid path. Which one gets superimposed depends on how you choose to imitate a cel-shaded image. You can either make the base paths the lighter colour and superimpose the darker "shaded" paths above (the traditional approach in raster images masked in GIMP or Photoshop), or you can make the base paths the darker shaded colour and superimpose the lighter paths on top.
I forget which approaches I used in the following examples but feel free to download the SVG files and study them in Inkcape for an idea of what I mean....
and I mean a lot
Of working with anime studio.
For a more traditional drawing program, MyPaint is another good one I use. THAT one would require a drawing tablet, though.
But thank you, though. Wish you were around when I made it. -v-