edit the slider before hitting start. hit start to render. I would recommend turbowarp: https://scratch.mit.edu/projects/1316649784/ How it works: -at each pixel, it shoots a "ray", a simulated beam of light. -the ray bends based on the laws of physics. -if it hits the event horizon, then it is painted black, because light can't escape, so no light could have traveled from there to the pixel. -if it hits the star it is painted yellow because the star could have emited that light so that it would hit the pixel. -after a certain amount of steps, if it hasn't hit either, it is painted blue.
I was researching how you simulate blackholes and found this meathod.