Any ideas about how I could make this rotate when dragged around the circle?

Question

I want to make it so you can click on the red circle and move it around the big black circle and I want the black line to rotate with the red circle, if you get what I mean. I can't figure out a way to determine how many degrees to rotate the parent based on cursor position though, any ideas?

https://code.sololearn.com/Wk4U4j1uyOE2/?ref=app

Answer 1

Karak10 You can find in web the needed info about vectors.
These examples help you to understanding the aplication of the theory in a code:

https://code.sololearn.com/cbwAWWo1vUn4/?ref=app

https://code.sololearn.com/W4teuZ25JqTM/?ref=app

Answer 2

I think Math.atan2() method is what I am looking for, I didn't have time to check it yet but I will try tomorrow. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/atan2

Answer 3

JaScript I think I made it, it's not exactly the project I was trying to make, it is a test, but I will have no problem making the main project now that I know how to get the angle based on the mouse position, all I have to do is change the events and make it rotate whenever the red ball is dragged.

https://code.sololearn.com/WA19A20A7A18/?ref=app

Answer 4

360 or 2pi. You can work with a vector.

Answer 5

JaScript I don't know how though
Edit: nevermind, I did some research, I had learned to work with vectors in school in the past, I just didn't realize what vectors are because I'm not a native english speaker and in my language they are called different, I need to study them a little again to remember them since its been a while I have worked with them but I think I will find a way to make what I want.

Answer 6

Your code is cool Karak10 .
I tried it with a touchscreen and it works very well.