In-Game paint scheme system

Hi, it’s the first time I ask something on the forums,

It’s the first time I use the node editor for materials and I managed to create a system that can let me choose a paint scheme inside blender. I’m trying to find a way to do this inside the game engine.

(Maybe you’ll understand what I’ve did with this)

Is it possible have an input for the nodes indirectly from a script inside the game engine?

Sorry if it’s unclear, English isn’t my main language, I do my best.

It’s called object colour.

Simply look for the check box ‘object color’ in the materials settings, then go to the object tab, and change the color!

Thanks for answering!
You have a good idea, if I want primary, secondary and tertiary color to have the same tint,

But what if I want to have different tints for primary, secondary and tertiary color ?