#include "defs.h"

/* chose routine for sort on nearest */

DPIN chosen(strt, prev)
	DPIN strt; 
	PIN prev;
{
	INT	bdist, bx=0, by=0;
	L_INT	xsum, ysum;
	REG DPIN dv;
	DPIN	best, prepin;
	REG PIN pp;
	REG INT del;
	DPIN1	dtmp;
	PIN1	tmp;

	if (prev == 0)
	{
		bdist = 0;
		xsum = 0;
		ysum = 0;
		for (dv = strt; dv < &pinvec[npins]; dv++)
		{
			pp = dv->pinp;
			bdist++;
			xsum += pp->x;
			ysum += pp->y;
		}
		tmp->x = xsum / bdist;
		tmp->y = ysum / bdist;
		dtmp->pinp = tmp;
		prepin = dtmp;
	}
	best = 0;
	for (dv = strt; dv < &pinvec[npins]; dv++)
	{
		del = distance(prepin,dv);
		pp = dv->pinp;
		if (best)
		{
			if (prev)
			{
				if (del > bdist) continue;
			}
			else if (del < bdist) continue;
			if (del == bdist)
			{
				if (pp->x > bx) continue;
				if (pp->x == bx && pp->y > by)
					continue;
			}
		}
		best = dv;
		bdist = del;
		bx = pp->x;
		by = pp->y;
	}
	return(best);
}