Incomplete SVG path specfication

[respatialized]

Incomplete SVG path specfication

[postspectacular]

Hi @respatialized - thank you so much for taking the time to create such a detailed issue & proposal to extend that current (half-baked) functionality! Most (if not all) of these things mentioned are already addressed by the newer TypeScript version of this library (not really the same, more of a rewrite) and should be pretty trivial to port to Clojure:

https://github.com/thi-ng/umbrella/blob/develop/packages/geom/src/path-from-svg.ts

That path parser implementation (~150 lines) too has no extra dependencies other than some constants, small utils and various vector ops (the latter should all be avail in the Clojure version too), all from the same thi.ng/umbrella monorepo:

• https://github.com/thi-ng/umbrella/blob/develop/packages/geom/src/path-builder.ts
• https://github.com/thi-ng/umbrella/blob/develop/packages/math/src/angle.ts#L72
• https://github.com/thi-ng/umbrella/blob/develop/packages/strings/src/groups.ts#L15
• https://github.com/thi-ng/umbrella/tree/develop/packages/vectors

I'd maybe start with this. The parser is currently undocumented (can prioritize that if it'd help you to get started), but it's been used in production since 2019 and was tested this with hundreds of SVG production files created by different tools (Illustrator, Inkscape, svgo optimizer, handwritten files, W3C)... FWIW I too started with a BNF, but had lots of issues dealing with most of the optimized SVG files and so ended up with this handwritten parser instead...

[respatialized]

Great, thanks for pointing me in the right direction! I definitely have more than enough to go on now.

[respatialized]

@postspectacular One question/clarification before I refine a concrete implementation further: the current implementation of parse-svg-coords is lazy, yielding a sequence of segments. For API compatibility, I assume this means that my new implementation should also be lazy, correct?

[respatialized]

@postspectacular I have a draft PR that implements more complete parsing of SVG paths, but I think there are a few unresolved questions about scope that I would appreciate some thoughts on!

#98