first of all, you need to convert Decart (Cartesian) coordinates (X,Y,Z) to Spherical coordinates (r,phi, theta). Spherical - is a 3D variant of polar coordinates.
then, you have to sort your array of spherical coordinates by "phi" (phi[i] < phi[i+1] = counterclockwise. phi[i] > phi[i+1] = clockwise. if you have two points with the same phi, compare "r" and "theta" values).
and when sort is done, you can convert polar coordinates of your sorted array back to decart.
/*
DECART
AcGePoint3d::x - X
AcGePoint3d::y - Y
AcGePoint3d::z - Z
SPHERICAL
AcGePoint3d::x - r
AcGePoint3d::y - phi
AcGePoint3d::z - theta
*/
AcGePoint3d Decart2Spherical(AcGePoint3d c)
{
AcGePoint3d p;
p.x=sqrt(c.x*c.x+c.y*c.y+c.z*c.z);
p.y=acos(c.x/sqrt(c.x*c.x+c.y*c.y))*(c.y>=0?1:-1);
p.z=acos(c.z/p.x);
return p;
}
AcGePoint3d Spherical2Decart(AcGePoint3d p)
{
decart d;
d.x=p.x*cos(p.y)*sin(p.z);
d.y=p.x*sin(p.y)*sin(p.z);
d.z=p.x*cos(p.z);
return d;
}
almost forgot. may be, before convertation you will need to subtract "A" coords from the rest points, to make "A" a zero point and append "A" after Spheriacal2Decart. In most cases it's unnecessary, but who knows 🙂
