It would be nice to have explanations and comparisons of the techniques that are employed for the current behavior and the new behavior. The color gradient criticism feels valid from an aesthetic standpoint but the problem seems to be that a simple linear interpolation doesn't provide the desired color properties. This raises the question as to what exactly are the desired color properties from a technical standpoint and when is each technique applicable. Say we changed all color interpolations from an interpolation in RGB space to HSV space (as I imagine the color gradients suggested are achieved), would this have any unforeseen consequences?
thrdbndndn|3 years ago
The value of your nominal R,G,B number is the result of using the original "intensity" (brightness or similar) and then raise it to the power of gamma (typically 1/2.2). The purpose of this is to give more "bits" around lower end (darker end) where human eyes are more sensitive [1]. If we don't do gamma and have relatively low bit depth (like your typical 8-bit), it's very easy to produce banding at dark gradient areas.
Up to this point, there is nothing wrong.
However, if you want to average two colors (which affects almost all the operations that can happen on bitmap images, including gradient, blending, resizing, blurring, etc...), the correct way, just like real-world physics, is to average them in original linear form/value; but most of applications/implementations, as shown in this page, are just averaging their nominal "gamma'd" values.
[1] There is often a common belief to say that the introducing of gamma space historically was because of how CRT screen used to work (the relationship between electricity intensity and brightness etc.). But most of in-depth articles about this topic say that's just a coincidence.
hummusandsushi|3 years ago