Unreal has a function called "construct" (or something similar, been a while) where the setting of a public variable (export in Godot) will update the object in the editor viewport. Effectively, it's a script that runs while the object is being edited, so you can add variables or logic that will show before you run the game. Is this possible in Godot?
I add an export variable called "is_red". If true, the sprite turns red. When I run the game, the change will show, but is there a way to show that change in the editor when I select the variable in the inspector?