Looks reasonably efficient for what it is, but looping over every comet for every pixel is pretty expensive. Claude has done its due diligence with stuff like // Cheapest check first: vertical distance but what you have here is essentially a ray tracer.
It would probably be faster to iterate over the comets and draw into a framebuffer array in beforeRender then just look up the value in render3D. You could even get the tails for free by attenuating the framebuffer as I do for ‘motion blur’ in these patterns: LEDaliClock matrix pattern - #10 by sorceror and Yet another approach to text rendering (WIP) - #23 by sorceror .
I would be interested to hear what Claude can make of this idea!