Green out to Gray in

Green is map, gray is just like single value. As far as I know, only controls can be plugged into greys.

I think they should have a script type that can output a grey control, like there's map script, and curve script, there should be a single value script too.

They really only need 2 very simple components to plug into grey inputs.

A 'curve to grey' and a 'map to grey'.

Curve to grey would just have a curve input and a 0-1 slider and it just takes the height of the curve at the point the slider says.

Map to gray would have 1 sliders for co-ordinates and it just takes brightness at that point.

They would probably also need checkboxes to switch between floating point or integer, and would be nice to have remapping like with controls, in fact they'd probably need remapping so they can plug into the dropdown box type inputs, which have a limited number of inputs or checkbox inputs that only have 2 options.

that would be great if it possible

Taking your example of assemble HSB to Perlin noise stretch, the question becomes how do you create the B channel. If you were to create the B channel with a slider, you could plug the same slider into the Perlin noise stretch input.

ThreeDee, I want to use all kinds of math on the input slider, then feed it to components. The stretch on the perlin was just an example for a gray input.
Right now there doesn't seem to be a way to manipulate the slider values.

Just as an example, suppose I have an IntSlider with a range of 1 to 100. I want to be able to take it's value, call it X, and run it through ((((X+1)^2) / 2) + 1) and then use the result as a gray node input.

I still have much to learn ThreeDee, so some of these work arounds are new to me. I will have to dig into the wiki and some snippets.

Anyway, it's cool that we have all those RGB math components, I just wish there was a Value Math set too.