Question

I am drawing an imaginary circle around the middle of a button.

The radius of the circle is the Height/2 if Height>Width or Width/2 if Width>Height.
Now i have to calculate which coordinates (in pixels) are in this circle.
The idea is that if e.g. the mouse cursor hovers over that circle, something happens.

Answer 1

You are inside the circle when this equation is satisfied:

Math.pow(mouse_pos_x-center_circle_x,2)+Math.pow(mouse_pos_y-center_circle_y,2)<Math.pow(radius,2)