Coordinates of point where arc ended?

Question

Here is what I have:

radius of circle = 100px

starting angle = 90 deg
ending angle = 0 deg
direction of arc = clockwise

Is there a way I can find coordinates of point where I ended drawing arc?

This is what it looks like.

Answer 1

Let the centre of the circle be at (a,b).

At any point on the circle, let$ \theta $ be the angle (measured in radians) made with the horizontal.

The angle in radians is just the angle in degrees rescaled. If D is the angle in degrees then $\theta = D / 360 * 2 \pi.$

So $\theta=0$ is the point (a+100,b),100px to the right of the centre of the circle.$ \theta =\pi/2$ is the point (a, b+100), 100px above the centre of the circle.

Any point on the circle is at $(a + 100 cos(\theta), b + 100 sin(\theta)).$