I want to generate colors that go well with a given UIColor (Triadic, Analogues, Complement etc).
I have read a lot of posts like this and this and this. In the last post, The answerer suggested going to easyrgb.com. So I went there. I learnt that I need to "rotate" the hue by some degrees if I want to generate those color schemes. For example, for Triadic colors, I need to rotate it by ± 120 degrees.
I know that I can get a color's hue by calling getHue(:saturation:brightness:), but how can I "rotate" it? Isn't the hue returned by the method a number? A number between 0 and 1? This makes no sense to me!
I think the first post might have the answer but the code is written in python. I only learnt a little bit of python so I don't quite know what this means:
h = [(h+d) % 1 for d in (-d, d)] # Rotation by d
From the comment, I see that this line somehow rotates the hue by d degrees. But I don't know what that syntax means.
Can anyone tell me how to rotate the hue, or translate the above code to swift?
The hue component ranges from 0.0 to 1.0, which corresponds to the angle from 0º to 360º in a color wheel (compare Wikipedia: HSL and HSV).
To "rotate" the hue component by n degrees, use:
let n = 120 // 120 degrees as an example
hue = fmod(hue + CGFloat(n)/360.0, 1.0)
The fmod() function is used to normalize the result of
the addition to the range 0.0 to 1.0.
The hue for the complementary color would be
let hueComplement = fmod(hue + 0.5, 1.0)