I'm trying to invert the colors from the screen. I tried the shader system but I'm not really experiences with shaders or where i should put the shader. I searched something about a backbuffer copy, but didn't really understood it very well. If someone could help me on how is this done, or direct me to where i could learn this? I did tried searching for invert color shaders in GLSL and tried to replicate it in Godot, to no success.