Numeric values for sprite

I am following this example: three.js examples
This is code of the example: three.js/examples/webgl_geometry_colors_lookuptable.html at 134ff886792734a75c0a9b30aa816d19270f8526 · mrdoob/three.js · GitHub
As you can see there is a sprite without numeric values. I want to it like this:

How can i add this numeric values on sprite?

But you mean literally? Like, how to add labels next to the sprite?

Or how to adjust gradient of linear interpolation (ie. which color appears at which stage / stop)

I’m actually asking for the best and simplest way to do this. I have min and max numeric values. Using these values, I want to sort these values from top to bottom on the right side of the sprite.