#303 Thumbnails of SVGs rendered incorrectly

[William Kendrick]

When accessing "New" and choosing a starter image, I noticed that a few -- e.g. the Elephant -- are rendered incorrectly in the thumbnail shown in the "New" dialog. (See elephant-t.png, the source SVG elephant.svg, and an example of what it looks like when loaded in Tux Paint, elephant-tp.jpg)

This thumbnail is constructed using ImageMagick convert (directly; not by invoking Inkscape) during the make build process.

This is using ImageMagick packaged for Ubuntu 24.04.4 LTS as of 2026-05-23. convert --version output:

Version: ImageMagick 6.9.12-98 Q16 x86_64 18038 https://legacy.imagemagick.org
Copyright: (C) 1999 ImageMagick Studio LLC
License: https://imagemagick.org/script/license.php
Features: Cipher DPC Modules OpenMP(4.5) 
Delegates (built-in): bzlib djvu fftw fontconfig freetype heic jbig jng jp2 jpeg lcms lqr ltdl lzma openexr pangocairo png raw tiff webp wmf x xml zlib

The SVG originated in 2009, with some tweaks by @perepujal in 2020 (https://sourceforge.net/p/tuxpaint/tuxpaint/ci/db09aacf4b/). I don't recall it ever appearing like this until I noticed today, so I assume it's a bug with my version of ImageMagick.

That said, I assume it might affect others building Tux Paint from source, so finding a work-around for issues like this would be helpful.

[William Kendrick]

For what it's worth, we seem to use rsvg-convert[*] for the SVG->PNG conversion (for PNG alternatives to SVG images) in the tuxpaint-stamps project. (Then follow it up with convert -trim to trim any border/whitepsace.)

I'll ask the tuxpaint-maintainers list what people think of changing tools, and who else might be noticing this bug.

[*] From the librsvg2-bin package in Ubuntu, part of the Librsvg project (https://wiki.gnome.org/Projects/LibRsvg -- note: wiki to be deprecated; see also https://gitlab.gnome.org/GNOME/librsvg)

[William Kendrick]

Thread: https://sourceforge.net/p/tuxpaint/mailman/tuxpaint-maintainers/thread/ahF9Q6O8dkSuX6yr%40bill-t480s/#msg59338138