info343/lectures/s5/resources/wz_jsgraphics.js

/* This notice must be untouched at all times.

wz_jsgraphics.js    v. 3.00
The latest version is available at
http://www.walterzorn.com
or http://www.devira.com
or http://www.walterzorn.de

Copyright (c) 2002-2004 Walter Zorn. All rights reserved.
Created 3. 11. 2002 by Walter Zorn (Web: http://www.walterzorn.com )
Last modified: 4. 2. 2007

Performance optimizations for Internet Explorer
by Thomas Frank and John Holdsworth.
fillPolygon method implemented by Matthieu Haller.

High Performance JavaScript Graphics Library.
Provides methods
- to draw lines, rectangles, ellipses, polygons
   with specifiable line thickness,
- to fill rectangles, polygons, ellipses and arcs
- to draw text.
NOTE: Operations, functions and branching have rather been optimized
to efficiency and speed than to shortness of source code.

LICENSE: LGPL

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License (LGPL) as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA,
or see http://www.gnu.org/copyleft/lesser.html
*/


var jg_ok, jg_ie, jg_fast, jg_dom, jg_moz;


function chkDHTM(x, i)
{
   x = document.body || null;
   jg_ie = x && typeof x.insertAdjacentHTML != "undefined" && document.createElement;
   jg_dom = (x && !jg_ie &&
      typeof x.appendChild != "undefined" &&
      typeof document.createRange != "undefined" &&
      typeof (i = document.createRange()).setStartBefore != "undefined" &&
      typeof i.createContextualFragment != "undefined");
   jg_fast = jg_ie && document.all && !window.opera;
   jg_moz = jg_dom && typeof x.style.MozOpacity != "undefined";
   jg_ok = !!(jg_ie || jg_dom);
}

function pntCnvDom()
{
   var x = this.wnd.document.createRange();
   x.setStartBefore(this.cnv);
   x = x.createContextualFragment(jg_fast? this.htmRpc() : this.htm);
   if(this.cnv) this.cnv.appendChild(x);
   this.htm = "";
}

function pntCnvIe()
{
   if(this.cnv) this.cnv.insertAdjacentHTML("BeforeEnd", jg_fast? this.htmRpc() : this.htm);
   this.htm = "";
}

function pntDoc()
{
   this.wnd.document.write(jg_fast? this.htmRpc() : this.htm);
   this.htm = '';
}

function pntN()
{
   ;
}

function mkDiv(x, y, w, h)
{
   this.htm += '<div style="position:absolute;'+
      'left:' + x + 'px;'+
      'top:' + y + 'px;'+
      'width:' + w + 'px;'+
      'height:' + h + 'px;'+
      'clip:rect(0,'+w+'px,'+h+'px,0);'+
      'background-color:' + this.color +
      (!jg_moz? ';overflow:hidden' : '')+
      ';"><\/div>';
}

function mkDivIe(x, y, w, h)
{
   this.htm += '%%'+this.color+';'+x+';'+y+';'+w+';'+h+';';
}

function mkDivPrt(x, y, w, h)
{
   this.htm += '<div style="position:absolute;'+
      'border-left:' + w + 'px solid ' + this.color + ';'+
      'left:' + x + 'px;'+
      'top:' + y + 'px;'+
      'width:0px;'+
      'height:' + h + 'px;'+
      'clip:rect(0,'+w+'px,'+h+'px,0);'+
      'background-color:' + this.color +
      (!jg_moz? ';overflow:hidden' : '')+
      ';"><\/div>';
}

var regex =  /%%([^;]+);([^;]+);([^;]+);([^;]+);([^;]+);/g;
function htmRpc()
{
   return this.htm.replace(
      regex,
      '<div style="overflow:hidden;position:absolute;background-color:'+
      '$1;left:$2;top:$3;width:$4;height:$5"></div>\n');
}

function htmPrtRpc()
{
   return this.htm.replace(
      regex,
      '<div style="overflow:hidden;position:absolute;background-color:'+
      '$1;left:$2;top:$3;width:$4;height:$5;border-left:$4px solid $1"></div>\n');
}

function mkLin(x1, y1, x2, y2)
{
   if(x1 > x2)
   {
      var _x2 = x2;
      var _y2 = y2;
      x2 = x1;
      y2 = y1;
      x1 = _x2;
      y1 = _y2;
   }
   var dx = x2-x1, dy = Math.abs(y2-y1),
   x = x1, y = y1,
   yIncr = (y1 > y2)? -1 : 1;

   if(dx >= dy)
   {
      var pr = dy<<1,
      pru = pr - (dx<<1),
      p = pr-dx,
      ox = x;
      while(dx > 0)
      {--dx;
         ++x;
         if(p > 0)
         {
            this.mkDiv(ox, y, x-ox, 1);
            y += yIncr;
            p += pru;
            ox = x;
         }
         else p += pr;
      }
      this.mkDiv(ox, y, x2-ox+1, 1);
   }

   else
   {
      var pr = dx<<1,
      pru = pr - (dy<<1),
      p = pr-dy,
      oy = y;
      if(y2 <= y1)
      {
         while(dy > 0)
         {--dy;
            if(p > 0)
            {
               this.mkDiv(x++, y, 1, oy-y+1);
               y += yIncr;
               p += pru;
               oy = y;
            }
            else
            {
               y += yIncr;
               p += pr;
            }
         }
         this.mkDiv(x2, y2, 1, oy-y2+1);
      }
      else
      {
         while(dy > 0)
         {--dy;
            y += yIncr;
            if(p > 0)
            {
               this.mkDiv(x++, oy, 1, y-oy);
               p += pru;
               oy = y;
            }
            else p += pr;
         }
         this.mkDiv(x2, oy, 1, y2-oy+1);
      }
   }
}

function mkLin2D(x1, y1, x2, y2)
{
   if(x1 > x2)
   {
      var _x2 = x2;
      var _y2 = y2;
      x2 = x1;
      y2 = y1;
      x1 = _x2;
      y1 = _y2;
   }
   var dx = x2-x1, dy = Math.abs(y2-y1),
   x = x1, y = y1,
   yIncr = (y1 > y2)? -1 : 1;

   var s = this.stroke;
   if(dx >= dy)
   {
      if(dx > 0 && s-3 > 0)
      {
         var _s = (s*dx*Math.sqrt(1+dy*dy/(dx*dx))-dx-(s>>1)*dy) / dx;
         _s = (!(s-4)? Math.ceil(_s) : Math.round(_s)) + 1;
      }
      else var _s = s;
      var ad = Math.ceil(s/2);

      var pr = dy<<1,
      pru = pr - (dx<<1),
      p = pr-dx,
      ox = x;
      while(dx > 0)
      {--dx;
         ++x;
         if(p > 0)
         {
            this.mkDiv(ox, y, x-ox+ad, _s);
            y += yIncr;
            p += pru;
            ox = x;
         }
         else p += pr;
      }
      this.mkDiv(ox, y, x2-ox+ad+1, _s);
   }

   else
   {
      if(s-3 > 0)
      {
         var _s = (s*dy*Math.sqrt(1+dx*dx/(dy*dy))-(s>>1)*dx-dy) / dy;
         _s = (!(s-4)? Math.ceil(_s) : Math.round(_s)) + 1;
      }
      else var _s = s;
      var ad = Math.round(s/2);

      var pr = dx<<1,
      pru = pr - (dy<<1),
      p = pr-dy,
      oy = y;
      if(y2 <= y1)
      {
         ++ad;
         while(dy > 0)
         {--dy;
            if(p > 0)
            {
               this.mkDiv(x++, y, _s, oy-y+ad);
               y += yIncr;
               p += pru;
               oy = y;
            }
            else
            {
               y += yIncr;
               p += pr;
            }
         }
         this.mkDiv(x2, y2, _s, oy-y2+ad);
      }
      else
      {
         while(dy > 0)
         {--dy;
            y += yIncr;
            if(p > 0)
            {
               this.mkDiv(x++, oy, _s, y-oy+ad);
               p += pru;
               oy = y;
            }
            else p += pr;
         }
         this.mkDiv(x2, oy, _s, y2-oy+ad+1);
      }
   }
}

function mkLinDott(x1, y1, x2, y2)
{
   if(x1 > x2)
   {
      var _x2 = x2;
      var _y2 = y2;
      x2 = x1;
      y2 = y1;
      x1 = _x2;
      y1 = _y2;
   }
   var dx = x2-x1, dy = Math.abs(y2-y1),
   x = x1, y = y1,
   yIncr = (y1 > y2)? -1 : 1,
   drw = true;
   if(dx >= dy)
   {
      var pr = dy<<1,
      pru = pr - (dx<<1),
      p = pr-dx;
      while(dx > 0)
      {--dx;
         if(drw) this.mkDiv(x, y, 1, 1);
         drw = !drw;
         if(p > 0)
         {
            y += yIncr;
            p += pru;
         }
         else p += pr;
         ++x;
      }
   }
   else
   {
      var pr = dx<<1,
      pru = pr - (dy<<1),
      p = pr-dy;
      while(dy > 0)
      {--dy;
         if(drw) this.mkDiv(x, y, 1, 1);
         drw = !drw;
         y += yIncr;
         if(p > 0)
         {
            ++x;
            p += pru;
         }
         else p += pr;
      }
   }
   if(drw) this.mkDiv(x, y, 1, 1);
}

function mkOv(left, top, width, height)
{
   var a = (++width)>>1, b = (++height)>>1,
   wod = width&1, hod = height&1,
   cx = left+a, cy = top+b,
   x = 0, y = b,
   ox = 0, oy = b,
   aa2 = (a*a)<<1, aa4 = aa2<<1, bb2 = (b*b)<<1, bb4 = bb2<<1,
   st = (aa2>>1)*(1-(b<<1)) + bb2,
   tt = (bb2>>1) - aa2*((b<<1)-1),
   w, h;
   while(y > 0)
   {
      if(st < 0)
      {
         st += bb2*((x<<1)+3);
         tt += bb4*(++x);
      }
      else if(tt < 0)
      {
         st += bb2*((x<<1)+3) - aa4*(y-1);
         tt += bb4*(++x) - aa2*(((y--)<<1)-3);
         w = x-ox;
         h = oy-y;
         if((w&2) && (h&2))
         {
            this.mkOvQds(cx, cy, x-2, y+2, 1, 1, wod, hod);
            this.mkOvQds(cx, cy, x-1, y+1, 1, 1, wod, hod);
         }
         else this.mkOvQds(cx, cy, x-1, oy, w, h, wod, hod);
         ox = x;
         oy = y;
      }
      else
      {
         tt -= aa2*((y<<1)-3);
         st -= aa4*(--y);
      }
   }
   w = a-ox+1;
   h = (oy<<1)+hod;
   y = cy-oy;
   this.mkDiv(cx-a, y, w, h);
   this.mkDiv(cx+ox+wod-1, y, w, h);
}

function mkOv2D(left, top, width, height)
{
   var s = this.stroke;
   width += s+1;
   height += s+1;
   var a = width>>1, b = height>>1,
   wod = width&1, hod = height&1,
   cx = left+a, cy = top+b,
   x = 0, y = b,
   aa2 = (a*a)<<1, aa4 = aa2<<1, bb2 = (b*b)<<1, bb4 = bb2<<1,
   st = (aa2>>1)*(1-(b<<1)) + bb2,
   tt = (bb2>>1) - aa2*((b<<1)-1);

   if(s-4 < 0 && (!(s-2) || width-51 > 0 && height-51 > 0))
   {
      var ox = 0, oy = b,
      w, h,
      pxw;
      while(y > 0)
      {
         if(st < 0)
         {
            st += bb2*((x<<1)+3);
            tt += bb4*(++x);
         }
         else if(tt < 0)
         {
            st += bb2*((x<<1)+3) - aa4*(y-1);
            tt += bb4*(++x) - aa2*(((y--)<<1)-3);
            w = x-ox;
            h = oy-y;

            if(w-1)
            {
               pxw = w+1+(s&1);
               h = s;
            }
            else if(h-1)
            {
               pxw = s;
               h += 1+(s&1);
            }
            else pxw = h = s;
            this.mkOvQds(cx, cy, x-1, oy, pxw, h, wod, hod);
            ox = x;
            oy = y;
         }
         else
         {
            tt -= aa2*((y<<1)-3);
            st -= aa4*(--y);
         }
      }
      this.mkDiv(cx-a, cy-oy, s, (oy<<1)+hod);
      this.mkDiv(cx+a+wod-s, cy-oy, s, (oy<<1)+hod);
   }

   else
   {
      var _a = (width-(s<<1))>>1,
      _b = (height-(s<<1))>>1,
      _x = 0, _y = _b,
      _aa2 = (_a*_a)<<1, _aa4 = _aa2<<1, _bb2 = (_b*_b)<<1, _bb4 = _bb2<<1,
      _st = (_aa2>>1)*(1-(_b<<1)) + _bb2,
      _tt = (_bb2>>1) - _aa2*((_b<<1)-1),

      pxl = new Array(),
      pxt = new Array(),
      _pxb = new Array();
      pxl[0] = 0;
      pxt[0] = b;
      _pxb[0] = _b-1;
      while(y > 0)
      {
         if(st < 0)
         {
            pxl[pxl.length] = x;
            pxt[pxt.length] = y;
            st += bb2*((x<<1)+3);
            tt += bb4*(++x);
         }
         else if(tt < 0)
         {
            pxl[pxl.length] = x;
            st += bb2*((x<<1)+3) - aa4*(y-1);
            tt += bb4*(++x) - aa2*(((y--)<<1)-3);
            pxt[pxt.length] = y;
         }
         else
         {
            tt -= aa2*((y<<1)-3);
            st -= aa4*(--y);
         }

         if(_y > 0)
         {
            if(_st < 0)
            {
               _st += _bb2*((_x<<1)+3);
               _tt += _bb4*(++_x);
               _pxb[_pxb.length] = _y-1;
            }
            else if(_tt < 0)
            {
               _st += _bb2*((_x<<1)+3) - _aa4*(_y-1);
               _tt += _bb4*(++_x) - _aa2*(((_y--)<<1)-3);
               _pxb[_pxb.length] = _y-1;
            }
            else
            {
               _tt -= _aa2*((_y<<1)-3);
               _st -= _aa4*(--_y);
               _pxb[_pxb.length-1]--;
            }
         }
      }

      var ox = -wod, oy = b,
      _oy = _pxb[0],
      l = pxl.length,
      w, h;
      for(var i = 0; i < l; i++)
      {
         if(typeof _pxb[i] != "undefined")
         {
            if(_pxb[i] < _oy || pxt[i] < oy)
            {
               x = pxl[i];
               this.mkOvQds(cx, cy, x, oy, x-ox, oy-_oy, wod, hod);
               ox = x;
               oy = pxt[i];
               _oy = _pxb[i];
            }
         }
         else
         {
            x = pxl[i];
            this.mkDiv(cx-x, cy-oy, 1, (oy<<1)+hod);
            this.mkDiv(cx+ox+wod, cy-oy, 1, (oy<<1)+hod);
            ox = x;
            oy = pxt[i];
         }
      }
      this.mkDiv(cx-a, cy-oy, 1, (oy<<1)+hod);
      this.mkDiv(cx+ox+wod, cy-oy, 1, (oy<<1)+hod);
   }
}

function mkOvDott(left, top, width, height)
{
   var a = (++width)>>1, b = (++height)>>1,
   wod = width&1, hod = height&1, hodu = hod^1,
   cx = left+a, cy = top+b,
   x = 0, y = b,
   aa2 = (a*a)<<1, aa4 = aa2<<1, bb2 = (b*b)<<1, bb4 = bb2<<1,
   st = (aa2>>1)*(1-(b<<1)) + bb2,
   tt = (bb2>>1) - aa2*((b<<1)-1),
   drw = true;
   while(y > 0)
   {
      if(st < 0)
      {
         st += bb2*((x<<1)+3);
         tt += bb4*(++x);
      }
      else if(tt < 0)
      {
         st += bb2*((x<<1)+3) - aa4*(y-1);
         tt += bb4*(++x) - aa2*(((y--)<<1)-3);
      }
      else
      {
         tt -= aa2*((y<<1)-3);
         st -= aa4*(--y);
      }
      if(drw && y >= hodu) this.mkOvQds(cx, cy, x, y, 1, 1, wod, hod);
      drw = !drw;
   }
}

function mkRect(x, y, w, h)
{
   var s = this.stroke;
   this.mkDiv(x, y, w, s);
   this.mkDiv(x+w, y, s, h);
   this.mkDiv(x, y+h, w+s, s);
   this.mkDiv(x, y+s, s, h-s);
}

function mkRectDott(x, y, w, h)
{
   this.drawLine(x, y, x+w, y);
   this.drawLine(x+w, y, x+w, y+h);
   this.drawLine(x, y+h, x+w, y+h);
   this.drawLine(x, y, x, y+h);
}

function jsgFont()
{
   this.PLAIN = 'font-weight:normal;';
   this.BOLD = 'font-weight:bold;';
   this.ITALIC = 'font-style:italic;';
   this.ITALIC_BOLD = this.ITALIC + this.BOLD;
   this.BOLD_ITALIC = this.ITALIC_BOLD;
}
var Font = new jsgFont();

function jsgStroke()
{
   this.DOTTED = -1;
}
var Stroke = new jsgStroke();

function jsGraphics(cnv, wnd)
{
   this.setColor = new Function('arg', 'this.color = arg.toLowerCase();');

   this.setStroke = function(x)
   {
      this.stroke = x;
      if(!(x+1))
      {
         this.drawLine = mkLinDott;
         this.mkOv = mkOvDott;
         this.drawRect = mkRectDott;
      }
      else if(x-1 > 0)
      {
         this.drawLine = mkLin2D;
         this.mkOv = mkOv2D;
         this.drawRect = mkRect;
      }
      else
      {
         this.drawLine = mkLin;
         this.mkOv = mkOv;
         this.drawRect = mkRect;
      }
   };

   this.setPrintable = function(arg)
   {
      this.printable = arg;
      if(jg_fast)
      {
         this.mkDiv = mkDivIe;
         this.htmRpc = arg? htmPrtRpc : htmRpc;
      }
      else this.mkDiv = arg? mkDivPrt : mkDiv;
   };

   this.setFont = function(fam, sz, sty)
   {
      this.ftFam = fam;
      this.ftSz = sz;
      this.ftSty = sty || Font.PLAIN;
   };

   this.drawPolyline = this.drawPolyLine = function(x, y)
   {
      for (var i=x.length - 1; i;)
      {--i;
         this.drawLine(x[i], y[i], x[i+1], y[i+1]);
      }
   };

   this.fillRect = function(x, y, w, h)
   {
      this.mkDiv(x, y, w, h);
   };

   this.drawPolygon = function(x, y)
   {
      this.drawPolyline(x, y);
      this.drawLine(x[x.length-1], y[x.length-1], x[0], y[0]);
   };

   this.drawEllipse = this.drawOval = function(x, y, w, h)
   {
      this.mkOv(x, y, w, h);
   };

   this.fillEllipse = this.fillOval = function(left, top, w, h)
   {
      var a = w>>1, b = h>>1,
      wod = w&1, hod = h&1,
      cx = left+a, cy = top+b,
      x = 0, y = b, oy = b,
      aa2 = (a*a)<<1, aa4 = aa2<<1, bb2 = (b*b)<<1, bb4 = bb2<<1,
      st = (aa2>>1)*(1-(b<<1)) + bb2,
      tt = (bb2>>1) - aa2*((b<<1)-1),
      xl, dw, dh;
      if(w) while(y > 0)
      {
         if(st < 0)
         {
            st += bb2*((x<<1)+3);
            tt += bb4*(++x);
         }
         else if(tt < 0)
         {
            st += bb2*((x<<1)+3) - aa4*(y-1);
            xl = cx-x;
            dw = (x<<1)+wod;
            tt += bb4*(++x) - aa2*(((y--)<<1)-3);
            dh = oy-y;
            this.mkDiv(xl, cy-oy, dw, dh);
            this.mkDiv(xl, cy+y+hod, dw, dh);
            oy = y;
         }
         else
         {
            tt -= aa2*((y<<1)-3);
            st -= aa4*(--y);
         }
      }
      this.mkDiv(cx-a, cy-oy, w, (oy<<1)+hod);
   };

   this.fillArc = function(iL, iT, iW, iH, fAngA, fAngZ)
   {
      var a = iW>>1, b = iH>>1,
      iOdds = (iW&1) | ((iH&1) << 16),
      cx = iL+a, cy = iT+b,
      x = 0, y = b, ox = x, oy = y,
      aa2 = (a*a)<<1, aa4 = aa2<<1, bb2 = (b*b)<<1, bb4 = bb2<<1,
      st = (aa2>>1)*(1-(b<<1)) + bb2,
      tt = (bb2>>1) - aa2*((b<<1)-1),
      // Vars for radial boundary lines
      xEndA, yEndA, xEndZ, yEndZ,
      iSects = (1 << (Math.floor((fAngA %= 360.0)/180.0) << 3))
            | (2 << (Math.floor((fAngZ %= 360.0)/180.0) << 3))
            | ((fAngA >= fAngZ) << 16),
      aBndA = new Array(b+1), aBndZ = new Array(b+1);
      
      // Set up radial boundary lines
      fAngA *= Math.PI/180.0;
      fAngZ *= Math.PI/180.0;
      xEndA = cx+Math.round(a*Math.cos(fAngA));
      yEndA = cy+Math.round(-b*Math.sin(fAngA));
      aBndA.mkLinVirt(cx, cy, xEndA, yEndA);
      xEndZ = cx+Math.round(a*Math.cos(fAngZ));
      yEndZ = cy+Math.round(-b*Math.sin(fAngZ));
      aBndZ.mkLinVirt(cx, cy, xEndZ, yEndZ);

      while(y > 0)
      {
         if(st < 0) // Advance x
         {
            st += bb2*((x<<1)+3);
            tt += bb4*(++x);
         }
         else if(tt < 0) // Advance x and y
         {
            st += bb2*((x<<1)+3) - aa4*(y-1);
            ox = x;
            tt += bb4*(++x) - aa2*(((y--)<<1)-3);
            this.mkArcDiv(ox, y, oy, cx, cy, iOdds, aBndA, aBndZ, iSects);
            oy = y;
         }
         else // Advance y
         {
            tt -= aa2*((y<<1)-3);
            st -= aa4*(--y);
            if(y && (aBndA[y] != aBndA[y-1] || aBndZ[y] != aBndZ[y-1]))
            {
               this.mkArcDiv(x, y, oy, cx, cy, iOdds, aBndA, aBndZ, iSects);
               ox = x;
               oy = y;
            }
         }
      }
      this.mkArcDiv(x, 0, oy, cx, cy, iOdds, aBndA, aBndZ, iSects);
      if(iOdds >> 16) // Odd height
      {
         if(iSects >> 16) // Start-angle > end-angle
         {
            var xl = (yEndA <= cy || yEndZ > cy)? (cx - x) : cx;
            this.mkDiv(xl, cy, x + cx - xl + (iOdds & 0xffff), 1);
         }
         else if((iSects & 0x01) && yEndZ > cy)
            this.mkDiv(cx - x, cy, x, 1);
      }
   };

/* fillPolygon method, implemented by Matthieu Haller.
This javascript function is an adaptation of the gdImageFilledPolygon for Walter Zorn lib.
C source of GD 1.8.4 found at http://www.boutell.com/gd/

THANKS to Kirsten Schulz for the polygon fixes!

The intersection finding technique of this code could be improved
by remembering the previous intertersection, and by using the slope.
That could help to adjust intersections to produce a nice
interior_extrema. */
   this.fillPolygon = function(array_x, array_y)
   {
      var i;
      var y;
      var miny, maxy;
      var x1, y1;
      var x2, y2;
      var ind1, ind2;
      var ints;

      var n = array_x.length;
      if(!n) return;

      miny = array_y[0];
      maxy = array_y[0];
      for(i = 1; i < n; i++)
      {
         if(array_y[i] < miny)
            miny = array_y[i];

         if(array_y[i] > maxy)
            maxy = array_y[i];
      }
      for(y = miny; y <= maxy; y++)
      {
         var polyInts = new Array();
         ints = 0;
         for(i = 0; i < n; i++)
         {
            if(!i)
            {
               ind1 = n-1;
               ind2 = 0;
            }
            else
            {
               ind1 = i-1;
               ind2 = i;
            }
            y1 = array_y[ind1];
            y2 = array_y[ind2];
            if(y1 < y2)
            {
               x1 = array_x[ind1];
               x2 = array_x[ind2];
            }
            else if(y1 > y2)
            {
               y2 = array_y[ind1];
               y1 = array_y[ind2];
               x2 = array_x[ind1];
               x1 = array_x[ind2];
            }
            else continue;

             //  Modified 11. 2. 2004 Walter Zorn
            if((y >= y1) && (y < y2))
               polyInts[ints++] = Math.round((y-y1) * (x2-x1) / (y2-y1) + x1);

            else if((y == maxy) && (y > y1) && (y <= y2))
               polyInts[ints++] = Math.round((y-y1) * (x2-x1) / (y2-y1) + x1);
         }
         polyInts.sort(CompInt);
         for(i = 0; i < ints; i+=2)
            this.mkDiv(polyInts[i], y, polyInts[i+1]-polyInts[i]+1, 1);
      }
   };

   this.drawString = function(txt, x, y)
   {
      this.htm += '<div style="position:absolute;white-space:nowrap;'+
         'left:' + x + 'px;'+
         'top:' + y + 'px;'+
         'font-family:' +  this.ftFam + ';'+
         'font-size:' + this.ftSz + ';'+
         'color:' + this.color + ';' + this.ftSty + '">'+
         txt +
         '<\/div>';
   };

/* drawStringRect() added by Rick Blommers.
Allows to specify the size of the text rectangle and to align the
text both horizontally (e.g. right) and vertically within that rectangle */
   this.drawStringRect = function(txt, x, y, width, halign)
   {
      this.htm += '<div style="position:absolute;overflow:hidden;'+
         'left:' + x + 'px;'+
         'top:' + y + 'px;'+
         'width:'+width +'px;'+
         'text-align:'+halign+';'+
         'font-family:' +  this.ftFam + ';'+
         'font-size:' + this.ftSz + ';'+
         'color:' + this.color + ';' + this.ftSty + '">'+
         txt +
         '<\/div>';
   };

   this.drawImage = function(imgSrc, x, y, w, h, a)
   {
      this.htm += '<div style="position:absolute;'+
         'left:' + x + 'px;'+
         'top:' + y + 'px;'+
         'width:' +  w + 'px;'+
         'height:' + h + 'px;">'+
         '<img src="' + imgSrc + '" width="' + w + '" height="' + h + '"' + (a? (' '+a) : '') + '>'+
         '<\/div>';
   };

   this.clear = function()
   {
      this.htm = "";
      if(this.cnv) this.cnv.innerHTML = "";
   };

   this.mkOvQds = function(cx, cy, x, y, w, h, wod, hod)
   {
      var xl = cx - x, xr = cx + x + wod - w, yt = cy - y, yb = cy + y + hod - h;
      if(xr > xl+w)
      {
         this.mkDiv(xr, yt, w, h);
         this.mkDiv(xr, yb, w, h);
      }
      else
         w = xr - xl + w;
      this.mkDiv(xl, yt, w, h);
      this.mkDiv(xl, yb, w, h);
   };
   
   this.mkArcDiv = function(x, y, oy, cx, cy, iOdds, aBndA, aBndZ, iSects)
   {
      var xrDef = cx + x + (iOdds & 0xffff), y2, h = oy - y, xl, xr, w;

      if(!h) h = 1;
      x = cx - x;

      if(iSects & 0xff0000) // Start-angle > end-angle
      {
         y2 = cy - y - h;
         if(iSects & 0x00ff)
         {
            if(iSects & 0x02)
            {
               xl = Math.max(x, aBndZ[y]);
               w = xrDef - xl;
               if(w > 0) this.mkDiv(xl, y2, w, h);
            }
            if(iSects & 0x01)
            {
               xr = Math.min(xrDef, aBndA[y]);
               w = xr - x;
               if(w > 0) this.mkDiv(x, y2, w, h);
            }
         }
         else
            this.mkDiv(x, y2, xrDef - x, h);
         y2 = cy + y + (iOdds >> 16);
         if(iSects & 0xff00)
         {
            if(iSects & 0x0100)
            {
               xl = Math.max(x, aBndA[y]);
               w = xrDef - xl;
               if(w > 0) this.mkDiv(xl, y2, w, h);
            }
            if(iSects & 0x0200)
            {
               xr = Math.min(xrDef, aBndZ[y]);
               w = xr - x;
               if(w > 0) this.mkDiv(x, y2, w, h);
            }
         }
         else
            this.mkDiv(x, y2, xrDef - x, h);
      }
      else
      {
         if(iSects & 0x00ff)
         {
            if(iSects & 0x02)
               xl = Math.max(x, aBndZ[y]);
            else
               xl = x;
            if(iSects & 0x01)
               xr = Math.min(xrDef, aBndA[y]);
            else
               xr = xrDef;
            y2 = cy - y - h;
            w = xr - xl;
            if(w > 0) this.mkDiv(xl, y2, w, h);
         }
         if(iSects & 0xff00)
         {
            if(iSects & 0x0100)
               xl = Math.max(x, aBndA[y]);
            else
               xl = x;
            if(iSects & 0x0200)
               xr = Math.min(xrDef, aBndZ[y]);
            else
               xr = xrDef;
            y2 = cy + y + (iOdds >> 16);
            w = xr - xl;
            if(w > 0) this.mkDiv(xl, y2, w, h);
         }
      }
   };

   this.setStroke(1);
   this.setFont("verdana,geneva,helvetica,sans-serif", "12px", Font.PLAIN);
   this.color = "#000000";
   this.htm = "";
   this.wnd = wnd || window;

   if(!jg_ok) chkDHTM();
   if(jg_ok)
   {
      if(cnv)
      {
         if(typeof(cnv) == "string")
            this.cont = document.all? (this.wnd.document.all[cnv] || null)
               : document.getElementById? (this.wnd.document.getElementById(cnv) || null)
               : null;
         else if(cnv == window.document)
            this.cont = document.getElementsByTagName("body")[0];
         // If cnv is a direct reference to a canvas DOM node
         // (option suggested by Andreas Luleich)
         else this.cont = cnv;
         // Create new canvas inside container DIV. Thus the drawing and clearing
         // methods won't interfere with the container's inner html.
         // Solution suggested by Vladimir.
         this.cnv = document.createElement("div");
         this.cont.appendChild(this.cnv);
         this.paint = jg_dom? pntCnvDom : pntCnvIe;
      }
      else
         this.paint = pntDoc;
   }
   else
      this.paint = pntN;

   this.setPrintable(false);
}

Array.prototype.mkLinVirt = function(x1, y1, x2, y2)
{
   var dx = Math.abs(x2-x1), dy = Math.abs(y2-y1),
   x = x1, y = y1,
   xIncr = (x1 > x2)? -1 : 1,
   yIncr = (y1 > y2)? -1 : 1,
   p,
   i = 0;
   if(dx >= dy)
   {
      var pr = dy<<1,
      pru = pr - (dx<<1);
      p = pr-dx;
      while(dx > 0)
      {--dx;
         if(p > 0)    //  Increment y
         {
            this[i++] = x;
            y += yIncr;
            p += pru;
         }
         else p += pr;
         x += xIncr;
      }
   }
   else
   {
      var pr = dx<<1,
      pru = pr - (dy<<1);
      p = pr-dy;
      while(dy > 0)
      {--dy;
         y += yIncr;
         this[i++] = x;
         if(p > 0)    //  Increment x
         {
            x += xIncr;
            p += pru;
         }
         else p += pr;
      }
   }
   for(var len = this.length, i = len-i; i;)
      this[len-(i--)] = x;
};

function CompInt(x, y)
{
   return(x - y);
}