Add border to improve apperance on dark background

[ojab]

Before/after comparison on Mac OS X dock w/ dark theme: https://imgur.com/a/atI6l

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This change is

[highfive]

Thanks for the pull request, and welcome! The Servo team is excited to review your changes, and you should hear from @mbrubeck (or someone else) soon.

[mbrubeck]

I'm no graphic designer, but my first impression is that this is a little too bold. Would a soft glow work, like a light-colored drop shadow?

[highfive]

New code was committed to pull request.

[ojab]

Updated the PR, new image is the bottom one: https://imgur.com/a/QJfKN.

[ojab]

…and removed border on doge (so only sprocket has border), last one is top one: http://imgur.com/a/JkclL.

[highfive]

New code was committed to pull request.

[mbrubeck]

I think I'd prefer a glow or drop-shadow that is behind the logo, so that it doesn't change the look at all on a white background. Right now it makes the Rust "gear" look a little fuzzy-edged at certain sizes especially on light backgrounds, and creates some odd effects where the white lines stop, like here:

Here's an example with a white drop-shadow against a dark background:

The same thing might work well with a sharper outline placed behind the image, for a less glowy effect.

[larsbergstrom]

I like @mbrubeck's suggestion, provided that it also looks good on a light background.

Adding @zmike, the original creator of the icon, for his thoughts.

[zmike]

After examining the issue further and with a number of unmentioned background colors (e.g., black http://i.imgur.com/HstiKls.png), I think this is a good solution:

DELETED

It's a bit more subtle than the other images posted here, allowing the emphasis to remain on the logo itself rather than having the eyes drawn to the outline effect.

EDIT: I deleted the first one because I noticed some artifacts from the original logo that I wanted to clean up. The updated version:

http://i.imgur.com/uDgaEyT.png

[jdm]

We should make a decision here :)

[mbrubeck]

As the randomly-selected reviewer, I propose checking in @zmike's version. It's very similar to @ojab's latest, but fixes some minor artifacts and fuzziness. Any objections?

And by the way, thank you @ojab for filing this issue; any of these are a big improvement on dark backgrounds!

[ojab]

@zmike's version is too subtle and barely visible on HiDPI screen w/ native resolution (i. e. not 2x) here, but I assume that it's not so common setup
It looks better in default setup, so I think that it's the right choice.

[mbrubeck]

@zmike, want to file a new PR for that?

[Coder206]

Please keep me posted on this. I am planning on implementing this on Windows, a requirement is to have it converted to ".ico", so I would like to use this new icon :)