Continuous transitions (avoid snapping when interrupted mid-fade)

[HarryBouch96]

Hi,

I’ve noticed a behaviour with WLED transitions that feels unintuitive when using it in home automation scenarios.

Currently, if I send a colour change with a tt value (say, 5 seconds), it fades smoothly if I let it complete. But if I send another colour change while that fade is still in progress, the strip snaps immediately to the new colour and only then begins fading again (from that snapped target).

This means I get an alternating pattern of snap → fade → snap → fade if I’m driving the LEDs dynamically from Home Assistant

I understand that WLED is intentionally designed to be lightweight with no transition queueing, but when creating dynamic scenes in Home Assistant, the snapping behaviour looks more like a bug than a feature.

Would it be possible to add an optional mode (perhaps a toggle in LED Preferences or a JSON flag) where if a new transition is requested while a fade is still in progress, WLED computes the current interpolated LED colour at that exact moment, then begins a new fade from that colour to the new target? This way, transitions would appear continuous even when interrupted. For users who want the current "snap then fade” behaviour, the default could remain unchanged.

Thanks for all your work on WLED, it’s a really awesome project and has taught me so much!

[willmmiles]

It's quite complex to manage in the general case; -- the 0.16 code offers many transition styles, and handling all possible combinations in a reasonable way is non-trivial. That said, I do have some ideas on how to approach multi transition handling without too much wrangling in the code, and reasonable fallback behaviour under resource constraints (CPU or memory). I don't know if we'll get to this any time soon, but it is on my radar.

[blazoncek]

FYI the code is written such that allows seamles transition of color even if currently running transition is not over.

However, there are cases where this may not be feasible and in such case it will not transition correctly. There is also a possibility of a bug.