Subject: bug#74055: 31.0.50; color-lighten-name not lightening black

From: Mattias Engdegård <[email-masked]>
Date: Tue, 29 Oct 2024 13:54:45 +0100

28 okt. 2024 kl. 18.24 skrev Eli Zaretskii <[email-masked]>:

> Maybe there are widely-accepted de-facto standards for that?

Perhaps the documentation should said 'percentage points' instead of just 'percent' to be unambiguous, since the lightness value is relative to the white-point.

I'd say the old model (percentage points) is better because it results in changes that are perceptually more uniform. For example, with the current code,

  (color-lighten-name C 5)

has much less effect when C is a dark colour than for a light one. Therefore the change was probably a mistake in hindsight.

> Or maybe we should support more than one interpretation, by way of
> some user option?

Don't think so -- only really a good solution for user preferences, not for an API.