oseiskar/black-hole — reverse-engineered prompt

Build me a browser based interactive black hole simulation that shows realistic gravitational lensing around a Schwarzschild black hole. I want it to run in WebGL and use GPU shaders for the ray tracing so the scene feels smooth on a decent computer.

The user should be able to open a simple web page and watch a black hole bend the light from a starry background, with an accretion disk and an optional orbiting planet to make the motion easier to understand. Add a small GUI where I can change simulation quality, time scale, and toggle relativistic effects like Doppler shift, light travel time, Lorentz contraction, and other visual contributions.

Keep the units simple, with the Schwarzschild radius treated as 1 and light speed as 1 by default. Make it visually impressive but also include short notes in the app explaining that some textures and colors are illustrative rather than fully physically exact. Look up current WebGL and three.js docs online if you need to.