Convert ellipses circles

[alexjlockwood]

The ability to convert circles and ellipses to paths has been requested a few times, for example in #652.

This pull request adds the ability to do just that.

LMK what you think!

[strarsis]

Is this similar to this PR?: #652

[alexjlockwood]

@strarsis Yeah, except instead of creating a new plugin it adds the functionality to the existing plugin.

[alexjlockwood]

Also, sorry... the tests are failing because of jshint errors (I ported it from a personal project I wrote in es6 and forgot to fix the hoisting stuff :P). Easy to fix... but I'll wait to hear back on whether or not you want me to continue following through on this.

[drewnoakes]

Is there anything blocking this PR other than the jshint errors? I would be happy to address those if it'll get a PR merged. Can add unit tests too.

[GreLI]

Well, in general <path>'ll be longer then <circle> and <ellipse>—that's why I didn't it initially. So, there should be an option, I think. Like convertCircles, disabled by default.

[drewnoakes]

Here's a concrete example of the increase in size, assuming integral parameters:

<circle cx="100" cy="100" r="50"/>

<path d="M100 50a50 50 0 1 0 0 100 50 50 0 1 0 0-100z"/>

There might be cases where converting circles to paths allows further path merging to occur, resulting in a net gain. I haven't seen any mention of optimisation heuristics/backtracking though.

So adding a default-disabled option seems harmless, but I'm not sure whether it'd ever make sense to turn it on.

[GreLI]

Yes it might, but that is not certain.

[geekbleek]

I have a number of use cases for converting circles and ellipses - ultimately because I'm not trying to optimize file size - I'm trying to optimize compatibility of all my SVG files. If I can help with this PR please let me know!

[GreLI]

Few issues are here:

• it should be optional
• there're errors in code, it doesn't work
• lack of tests.

[strarsis]

@alexjlockwood: There are jshint errors which prevent the tests to pass:
https://travis-ci.org/svg/svgo/jobs/219732094#L246

[alexjlockwood]

Sorry about that, will try to fix that up now. :)

[alexjlockwood]

Blah... looks like I accidentally deleted my svgo fork. Is it possible to update the pull request if I've done that? Or will I have to create a new one...

[GreLI]

No idea, I'm afraid you have to make a new PR.

[alexjlockwood]

Going to close this and continue the work here: #818