FLASH MX Actionscript - Rotating Picture Gallery

Hi there ppls, i have obtained the following actionscript, it all works nicely...what happens basically there are numerous pictures that rotate in a 3d gallery....the rotation occurs horizontal, however I need it to rotate vertical here is the code:

walls = new array();
rad = Math.PI/180;
// number of items
max = 6;
// width of items
width = 50;
rat = width/100;
radius = (width*max)/Math.PI;
astep = -360/max;
dist = radius*2+50;
for (i=0; i<max; i++) {
      walls[i] = new Object();
      walls[i].y = 0;
      walls[i].x1 = Math.sin(astep*i*rad)*radius+Math.sin((astep*i+90)*rad)*width/2;
      walls[i].z1 = Math.cos(astep*i*rad)*radius+Math.cos((astep*i+90)*rad)*width/2;
      walls[i].x2 = Math.sin(astep*i*rad)*radius+Math.sin((astep*i-90)*rad)*width/2;
      walls[i].z2 = Math.cos(astep*i*rad)*radius+Math.cos((astep*i-90)*rad)*width/2;
}
//
function clicked (n) {
      _root.menu._xscale = _root.menu._yscale=20;
      _root.menu._x = 50;
      _root.menu._y = 200;
      _root.menu.gotoAndStop(2);
      _root.name_section = "section::" add n
}
function menuback () {
      _root.menu._xscale = _root.menu._yscale=100;
      _root.menu._x = 160;
      _root.menu._y = 120;
      _root.menu.gotoAndStop(1);
      _root.name_section = "main"
}
//
function Redraw (ya) {
      xa = 0;
      var cosYangle = Math.cos(ya*rad);
      var sinYangle = Math.sin(ya*rad);
      var cosXangle = Math.cos(xa*rad);
      var sinXangle = Math.sin(xa*rad);
      // rotation
      for (i=0; i<max; i++) {
            x = walls[i].x1;
            z = walls[i].z1;
            y = walls[i].y1;
            var tempz = (z*cosYangle)-(x*sinYangle);
            var tx = (z*sinYangle)+(x*cosYangle);
            var tz = (y*sinXangle)+(tempz*cosXangle);
            var ty = (y*cosXangle)-(tempz*sinXangle);
            var zratio = dist/(tz+dist);
            walls[i].sx1 = +tx*zratio;
            walls[i].sy1 = -ty*zratio;
            walls[i].size1 = 50*zratio;
            x = walls[i].x2;
            z = walls[i].z2;
            y = walls[i].y2;
            var tempz = (z*cosYangle)-(x*sinYangle);
            var tx = (z*sinYangle)+(x*cosYangle);
            var tz = (y*sinXangle)+(tempz*cosXangle);
            var ty = (y*cosXangle)-(tempz*sinXangle);
            var zratio = dist/(tz+dist);
            walls[i].sx2 = +tx*zratio;
            walls[i].sy2 = +ty*zratio;
            walls[i].size2 = 50*zratio;
      }
      // visualisation
      for (i=0; i<max; i++) {
            name = "sh" add i;
            _root.menu.ins.attachMovie("shape", name, i+1);
            _root.menu.ins[name].pic.gotoAndStop(i%7);
            _root.menu.ins[name].pic.name = i;
            _root.menu.ins[name].n = i;
            if (walls[i].size1<walls[i].size2) {
                  ratio = int((walls[i].size1/walls[i].size2)*1000);
                  _root.menu.ins[name]._x = walls[i].sx2/(r+1);
                  _root.menu.ins[name]._y = -walls[i].sy2/(r+1);
                  _root.menu.ins[name]._yscale = walls[i].size2/(r+1);
                  _root.menu.ins[name]._xscale = (walls[i].sx1-walls[i].sx2)/(r+1);
                  _root.menu.ins[name].pic._xscale = -100;
            } else {
                  ratio = int((walls[i].size2/walls[i].size1)*1000);
                  _root.menu.ins[name]._x = walls[i].sx1/(r+1);
                  _root.menu.ins[name]._y = -walls[i].sy1/(r+1);
                  _root.menu.ins[name]._yscale = walls[i].size1/(r+1);
                  _root.menu.ins[name]._xscale = (walls[i].sx2-walls[i].sx1)/(r+1);
            }
            _root.menu.ins[name]._alpha = 50;
            _root.menu.ins[name].gotoAndStop(1000-ratio);
      }
}
stop ();