What is rgb formula for a gradient going from white to blue?

Question

I want to have a button that has numbers in the range 0 ... 255. I'd like the color of the button to be white when it's zero and blue (RGB = (0,0,255)) when it is 255. How can I accomplish this? At first I tried to make it RGB = (0,0,0) in the beginning, but it will only make it black.

How can I accomplish this?

Answer 1

Simple linear interpolation between white (255,255,255) and blue (0,0,255) will do.

Answer 2

A gradient from blue to white would start with:

0,0,255

with values of the R and G increasing at the same rate: 1,1,255 ... 10,10,255 ... 255,255,255

The colors between the 2 will start to appear pastel blue, then greyish blue.