Maybe, I kind of like the darker look, I could add a toggle key for the old background, or maybe I could try something with filters and have the background react to various conditions.

@JetLennit a mouse click will launch a ball now. @dan11 contrast between ball and background is greater so it should be easier to see. @NikZ Added a rule that says if the ball is tiny its orbit is to degenerate to center so hopefully no infinite orbits will happen near center. :D

Oh yeah the spacebar thing, I do not really intend for that to be permanent, I want the ball to stick to the paddle before launch. I did not know if this idea would work out; that is partially the reason why it is so rough around the edges.

I'll see what I can do, left and right arrow will not be sufficient, maybe make the arrow keys zip the paddle to the 0,90,180,270 degree positions, WASD to gradually move to the 0,90,180,270 positions.

One tiny bug, I accidentally double clicked the '.' twice and it will stop the simulation from running. It is pretty cool to see it put the numbers in the display now. You could have a lot of fun with this - maybe evolve it into a graphing calculator? :D