[as2] 等間隔のカクカク渦巻き(3)

import flash.geom.Point;

var result = createOrderMatrix( 9 , 9 );
for(var i=0;i<result.length;i++){
  trace( result[i] );
}

function createOrderMatrix( xlength:Number , ylength:Number ):Array
{
  var p:Point = new Point( 0 , 0 );
  var totalLength = xlength*ylength;
  var matrix = new Array( ylength );
  for(var i=0;i<ylength;i++){
    matrix[i] = new Array( xlength );
  }
  var xh = Math.floor(xlength/2);
  var yh = Math.floor(ylength/2);
  var xflag = true;
  var yflag = false;
  var xm:Number, ym:Number, nx:Number, ny:Number;
  xm = ym = nx = ny = 1;
  
  matrix[yh][xh] = 0;
  for(var i=1;i<totalLength;i++)
  {
    if( xflag ){
      p.x += xm/Math.abs(xm);
      if( nx == p.x ){
        xm = -(Math.abs(xm)/xm)*(Math.abs(xm)+1);
        nx += xm;
        yflag = true; xflag = false;
      }
    }
    else if( yflag ){
      p.y += ym/Math.abs(ym);
      if( ny == p.y ){
        ym = -(Math.abs(ym)/ym)*(Math.abs(ym)+1);
        ny += ym;
        yflag = false; xflag = true;
      }
    }
    if( p.x+xh >= 0 && p.x+xh < xlength &&
             p.y+yh >= 0 && p.y+yh < ylength ){
      matrix[p.y+yh][p.x+xh] = i;
    } else {
      i--;
    }
  }
  return matrix;
}

72,73,74,75,76,77,78,79,80
71,42,43,44,45,46,47,48,49
70,41,20,21,22,23,24,25,50
69,40,19,6,7,8,9,26,51
68,39,18,5,0,1,10,27,52
67,38,17,4,3,2,11,28,53
66,37,16,15,14,13,12,29,54
65,36,35,34,33,32,31,30,55
64,63,62,61,60,59,58,57,56