How to assume spiral parameters?

Question

Could someone help me in understanding what paramaters assume to have such spiral as in this question:Draw equidistant points on a spiral?

I don't understant this parameter: rotation- Overall rotation of the spiral. ('0'=no rotation, '1'=360 degrees, '180/360'=180 degrees) I would be grateful if someone write some sets of parameters (sides,coils,rotation) to get spiral.

It's code in Matlab:

    clc 
clear all
centerX = 0
centerY = 0
radius = 10
coils = 30
rotation = 360
chord = 2
delta = 1

thetaMax = coils * 2 * pi;


awayStep = radius / thetaMax;

i = 1

for theta = (chord / awayStep):thetaMax; 


     away = awayStep * theta;


    around = theta + rotation;


     x(i) = centerX + cos ( around ) * away;
     y(i) = centerY + sin ( around ) * away;
    i = i + 1




    theta = theta + (chord / away);
    theta2 = theta + delta 
    away2 = away + awayStep * delta 
    delta = 2 * chord / ( away + away2 )
    delta = 2 * chord / ( 2*away + awayStep * delta )
     2*(away + awayStep * delta ) * delta == 2 * chord 
     awayStep * delta * 2 + 2*away * delta - 2 * chord == 0
    a= awayStep; b = 2*away; c = -2*chord

   delta = ( -2 * away + sqrt ( 4 * away * away + 8 * awayStep * chord ) ) / ( 2 * awayStep );

theta = theta +  delta;
end

v = [0 x]
w = [0 y]
scatter(v,w)

Thank you in advance