Hello zaneta!
Welcome to our forum and thanks for contacting us with your question!
I have prepared a little bit different demo for you with the usage of custom code written by Rafal. I have changed the marker to triangle and also I extended it to use another custom property "size" in
dial object, which controls the size of triangle dial. Besides this, the main logic is same as in your demo.
Demo: https://jsfiddle.net/BlackLabel/yo9ewavp/
Let me know if you have any further questions.
Kind regards!