how can I split the screen into two screens and make Gdx.input.setInputProcessor () accept two processors?

I want to draw in the first screen portion, and manipulate the buttons in the second part.

This is what I tried:

if (mouse.x <600) {
Gdx.input.setInputProcessor (new InputProcessor () {

Override
public boolean touchup (int arg0, int arg1, int arg2, int arg3) {
return false;
}
.
.
.
.
.
}
if (mouse.x> = 600) {
Gdx.input.setInputProcessor (stage);
}

the problem is that I have the ability to go from the first part to the second but I’m not allowed to go from the second to the first, it blocks the mouse coordinates in x = 600 This is what I tried