package com.well.www.user.xanthian.java.layouts;import java.util.*;import com.well.www.user.xanthian.java.structures.*;import com.well.www.user.xanthian.java.tools.*;import com.well.www.user.xanthian.java.ui.*;public class PolySpiralLayout{/*** Arbitrarily, use some polygon as our spiraling object.  Even numbers** of corners are easy, odd numbers are sadistic, because the traveller** can't just do trips in and trips out along the spiral arms in matched** pairs.*/ final static int CORNERS_IN_POLYGON = 5;  public static void layout  (    double cities[][],    int cityX,    int cityY,    double width,    double height  )  {    int numCities = cities.length;    double radius = Math.min ( width, height ) / 2.0D;    TravellerStatus.setCircumference( radius * 2.0D * Math.PI );/*** Arbitrarily, use an eight degree spin per spiral depth increase,** trying to make it harder for the algorithm to decide between doing** two arms at once or arm by arm in the outer fringes.  Ten degrees** seems to lead to attempting to walk two arms at once, five degrees to** one arm at at time.  Eight degrees is also sadistic, because when,** for large numbers of cities, the outer part beome more easily** connectable as rays rather than spiral arms, using eight degrees** produces 45 of those rays, an odd number, maikng them harder to join** into a tour.*/    final double ANGULAR_INCREASE = 2.0D * Math.PI / 45.0D;    double polygonAngle = 2.0D * Math.PI / (double) CORNERS_IN_POLYGON;    double center_x = width / 2.0D;    double center_y = height / 2.0D;    int naturalProblemSize =      (numCities + CORNERS_IN_POLYGON - 1) / CORNERS_IN_POLYGON;/*** The spiral gets too crowded going all the way to the center (though it** sure is pretty); just go 19/20ths of the way instead.*/    final int spiralingSize = ( naturalProblemSize * 20 ) / 19;    int currentCityNumber = 0;    for ( int i = 0; i < naturalProblemSize; i++ )    {      double currentRadius =        radius        *        (double) ( spiralingSize - i )        /        (double) spiralingSize;      for ( int j = 0; j < CORNERS_IN_POLYGON; j++ )      {        if ( currentCityNumber < numCities )        {          double currentAngle =            ( ( (double ) j)  * polygonAngle )            +            ( ( (double) i ) * ANGULAR_INCREASE );          cities[currentCityNumber][cityX] =            center_x + (currentRadius * Math.cos(currentAngle));          cities[currentCityNumber][cityY] =            center_y + (currentRadius * Math.sin(currentAngle));        }        currentCityNumber++;      }    }    TravellerStatus.setExactSolutionIsKnown( false );    PerturbLayout.layout( cities, cityX, cityY, width, height );  }}