Find coordinates of parallel lines within a circle sector

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Geometry is not my strongest subject and I can't find solution to my problem.

I'm writing algorithm that finds coordinates in a circle sector. There is $n$ amount of parallel lines, each with equal distance from each other, within circle sector. Below I attach image for reference:

Reference image...

Problem: Find coordinates of $(x_n,y_n)$ and $(p_n,q_n)$

Known variables:

$P$ - point (0, 0). Point P is the origin of the circle

$\alpha$ - triangle angle

$d$ - distance between parallel lines

$r$ - circle radius

So far I found formula for $x_n$ and $y_n$:

Values for $x_n$:

  1. $x_1$ = $\frac{d}{sin\alpha}$
  2. $x_n = n*x_1$

Values for $y_n$:

$y_n = 0$

I don't know how to find coordinates of $(p_n, q_n)$. I've been trying to solve this for a few hours now and I still can't find solution. Thank you in advance!

PS: Solidworks is only software that know how to use to show geometry. I don't know how to use interactive geometry software. Sorry for the inconvinience

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The problem is easier if you rotate the figure so that the oblique radius becomes horizontal. Then you intersect the circle of equation

$$u^2+v^2=r^2$$

with the horizontals

$$v_k=-kd.$$

The intersection points are thus

$$\left(\sqrt{r^2-v_k^2},v_k\right).$$

Now you can rotate to bring the figure back in the original position. It is convenient to use complex numbers and compute

$$p_k+iq_k=(u_k+iv_k)(\cos\alpha+i\sin\alpha).$$

enter image description here

The $(x_k,y_k)$ are easier.