mathematics - Moving an object in a circular path

I want to move one object (dot) in a circular path. How should I change the X and Y coordinates to accomplish this?

Answer

You can do that using simple math:

X := originX + cos(angle)*radius;
Y := originY + sin(angle)*radius;

(originX, originY) is the center of your circle. radius is its radius. That's it.

This works because the sine and cosine are mathematically related to the unit circle.

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