Creation of spring simulation

First, I tried asking GPT 4o mini to outright make a simulation of a spring pendulum attached to the cursor. What it gave me rendered nothing.
Second, I asked for something more simple. Just a ball that appears 50px below the cursor. That was fine on the first try.
After that, we tried a pendumlum, and that worked, but it just was transposed by the mouse and wasn't actually affected by the mouse movement.
Next I asked it to have the pendulum be properly influenced by the mouse, but even after a few different attempts at debugging itself, the best it could get was the right basic behavior but an improper pendulum angle update.
Everything GPT produced used no libraries and did all the math in the file.

Next I went to Copilot (unknown version) and asked for a rigidi pendulum attached to the cursor, and it worked (see the pendulum sim). It used matter-js for the physics.
I asked it to make the connection a spring, and it did that. I added a minor tweak to the spring coefficient and published that (see spring sim).

I think this was a lesson in using the right LLM for the job. Copilot seems better for entire code projects and knowing what libraries to use.
I will update here if I try writing this myself.

- Toady