[sph]

If one works with shaders, you get the best of both worlds just by dividing by 10:

  vec3 color = vec3(1.0, 0.3, 0.9);

One decimal digit ought to be enough for anyone.

[lpghatguy]

Take care here though, because shaders are almost always working in linear sRGB colors, while color codes are almost always defined in gamma-encoded sRGB.

This property makes it mildly annoying to copy color constants between different contexts.

[amelius]

Also if you divide by 10 your maximum is 0.9, not 1.0.

So you still need a calculator to map between the two.