How to make a truck crane calculator with a dynamic slider image?

Question

JavaScript

Tell me how such calculation calculators are made
https://stpmsk.ru/calc-load-capacity-crane/
https://mskran.ru/raschet-avtokrana
It is clear that in javascript ......
The algorithm itself is of interest.
What scripts, ready-made libraries are used?
How is the image rendered?
How is the slider attached to the image?
How are truck cranes retrieved from the database? (as far as I understand, there is an interaction between javascript and php)
How to implement such a script on wordpress (maybe there are already ready-made plugins, or services constructors)?

Answer 1

nothing complicated, really: resizing elements (sliding part) are rendered in svg, complex elements (arrow base, limiters) are just pictures. well, then comes the geometry to determine the position by coordinates.