I’d like to apply some color grading, and a makeshift vignette effect to this scene I have. Do I do that directly in the draw function? This is how I typically draw UI, however, I’ve been unable to draw and set a background color with transparency that way. I presumed I’d be able to use background() with a color that has a low alpha, and still see the things I have rendered in the scene. I’d love to be able to use setcontext directly on the camera’s render texture, but I’m sure that’s not allowed 
@arismoko background() clears the backbuffer entirely which is why it’s not working for you. In your case I’d suggest rendering a fullscreen rectangle with the correct colour instead as that won’t erase any work done already.
As for vignette, the best way would probably be using a shader.
Thank you! I’ll try that out (:
@arismoko Fantastic 
This works perfectly! I was trying to make my 3d snake game look like it was made on a gameboy, and using a rectangle at 0,0 with the dimensions of the screen and a green color does the trick! @Steppers