i think the easiest would be to use webdev resources...
You could also do it without if you copy three.js lib into injectables head.txt
And than use some markdown to inject the js.
Somethign similar like i did here:
But you gotta be careful on how you construct the markdown so that it does NOT refresh else you will have 0 performance (depending on complexity)
if you need to update the generated image you maybe can use a second markdown that adjusts some variables. but this will require quite some JS knowledge