Partial, an abstract Pebble watchface

Everywhere I go, people ask: How do you read your watch. Take a guess?

Density of time changes. If you are sprinting, milliseconds matter. If you are in a meeting, minutes matter. If you are on a holiday? Nothing should matter. Most of the watchfaces are too informative than they have to be, they are alarm clocks that disturb your peace, they urge you to rush. So here it is, Partial, a watchface that reminds you to relax, you don’t have to utilise every second.

How to read

The angle indicates the hour, e.g. it’s vertical at 12, horizontal at 3. The above example is showing 7 a.m. or 7 p.m.

The filling (area) of the half circle indicates percentage passed of the hour. At 00:01 will be a thin line, at 00:59 it will be a half circle. The above example is showing something around 40 minutues.


But how do I tell the time?

You don’t read it, you feel it. The good thing about half circle is that it’s hard to guess, trust me, you don’t need that much accuracy.

How do I tell if it’s 1am or 7am?

When it’s 1am, it fills the bottom half of the screen. When it’s 7am, it fills the upper half. But really, 6 hours is a long time, you can probably tell by instinct.

How do I tell if it’s a.m. or p.m.?

Just like a normal analog watchaface, you can’t.

Where can I get it

It is only available for Pebble, on the Rebble Appstore.

Alternatively, the source code is available on Github so you can build it yourself.

A little programming story. The area filled is the percentage passed of the hour, so to calculate the height of the filled area, I have to do integration. The area at a certain height is something like this: \int_{0}^{h} (1-x^2) dx Which means solving something like area = (\sqrt{1-x^2} * x + asin(x)) Which is too complicated for whatever does that mean. It turns out Pebble Time Round’s resolution is not very high, the radius is only 90 pixels, and the watchface only updates once a minute. Which means a simple brute force is good enough to find the correct answer.