Time 2 - "night mode" using RGB backlight?

[machinaeZER0]

Is there an existing issue for this?

• I have searched the existing issues

Proposed feature request

Given that the PT2 has an RGB backlight, it would be neat to have a "night mode" backlight toggle that used warmer hues in the evening (either through setting a time window or syncing to sunrise/sunset). Combined with the dynamic backlight setting, it feels like this would make for a very pleasant night viewing experience!

Alternatives

No response

Anything else?

No response

[saltedlolly]

Eric mentioned this is planned in the original announcement video.

[nick1udwig]

I'm putting together some PRs to implement this. Hope to have them posted soon!

[machinaeZER0]

Oh man, awesome!!

[nick1udwig]

PRs sent 🎉

[ericmigi]

cool! No guarantees we can take a look soon, but this is great to see thank yoU!

[smolikja]

I'd really love to see this feature make it into PebbleOS.

My main use case is essentially an f.lux / Night Shift mode for the Pebble Time 2 backlight. During the day I use a fairly warm/neutral backlight, but in complete darkness I'd like the backlight to become fully red.

One improvement I'd suggest over the current implementation in #1596 is a gradual transition rather than a hard switch at sunset/sunrise.

Ideally:

• the user chooses a Day Color and Night Color;
• the schedule can use local sunset/sunrise or custom times;
• the user can choose a transition duration, e.g. Instant / 30 / 60 / 90 / 120 minutes;
• the transition is centered around sunset and sunrise rather than starting only once sunset/sunrise occurs.

For example, with a 60-minute transition and sunset at 19:00, PebbleOS could gradually interpolate from the Day Color to the Night Color from 18:30 to 19:30, with sunset being the midpoint of the transition.

The same would happen in reverse around sunrise.

This also means PebbleOS would not need more detailed twilight data such as civil twilight start/end. The existing sunrise/sunset timestamps should be enough; the transition window can simply be derived from the selected duration.

For my own setup, I would use:

• Day Color: warm white / yellowish tint
• Night Color: pure red (#FF0000)
• Transition: approximately 60 minutes centered around sunset/sunrise

I think this would work particularly well together with Dynamic Backlight Intensity: the ambient sensor could continue controlling brightness while the day/night feature controls color.

Implementation-wise, it could be as simple as interpolating between the configured Day Color and Night Color according to the current position within the transition window. There should be no need to continuously update the backlight while it is off; PebbleOS could calculate the correct color when the backlight turns on and update it periodically only while needed.

Since #1596 already seems to contain most of the required system-level infrastructure, this feels like a natural extension of that work rather than a separate feature.

I'd be very interested in seeing #1596 revived and extended with this gradual transition behavior.