I just tried the first example with Inkscape and it keeps full precision. It’s a pity it wasn’t included in this post.
Yes, Inkscape is the missing elephant from the room. It’s a wonderful cross-platform FOSS application that’s helped me in a number of projects whose native format actually is SVG.
I’m a little surprised you don’t see 14/15 digits from any of these, which would roughly line up with the use of double precision floats. 7/8 digits of precision is plausibly a sign that the software is hiding single precision floats. I guess that would make sense since f32 gets used everywhere in rendering.
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