document.querySelector("head").appendChild(style);
  }
  amendCssOnce = 0;
}
var tooltipObj = document.createElement("span");
tooltipObj.className = "tl-tooltip";
tooltipObj.style.visibility = "hidden";
document.getElementsByClassName("content")[0].appendChild(tooltipObj);

function TimelineGraph(tx){
  var topObj = document.getElementById("timelineTable"+tx.iTableId);
  amendCss(tx.circleNodes, tx.showArrowheads);
  var canvasDiv;
  var railPitch;
  var mergeOffset;

    var y = to.y + node.h;
    var arrowSpace = from.y - y + (!from.id || from.r!=to.r ? node.h/2 : 0);
    var arw = arrowSpace < arrow.h*1.5 ? arrowSmall : arrow;
    var x = to.x + (node.w-line.w)/2;
    var y0 = from.y + node.h/2;
    var y1 = Math.ceil(to.y + node.h + arw.h/2);
    var n = drawLine(line,color,x,y0,null,y1);


    addToolTip(n,id)
    x = to.x + (node.w-arw.w)/2;
    n = drawBox(arw.cls,null,x,y);
    if(color) n.style.borderBottomColor = color;
    addToolTip(n,id)
  }
  function drawDotted(from,to,color,id){
    var x = to.x + (node.w-line.w)/2;
    var y0 = from.y + node.h/2;
    var y1 = Math.ceil(to.y + node.h);
    var n = drawLine(dotLine,null,x,y0,null,y1)
    if( color ) n.style.borderColor = color
    addToolTip(n,id)
  }
  function addToolTip(n,id){
    if( id ){
      n.onmouseenter = tooltipEnter
      n.onmouseleave = tooltipLeave
      n.onclick = tooltipClick
      n.setAttribute("data-ix",id-tx.iTopRow)
    }
  }
  /* Draw thin horizontal or vertical lines representing merges */
  function drawMergeLine(x0,y0,x1,y1){
    drawLine(mLine,null,x0,y0,x1,y1);
  }
  function drawCherrypickLine(x0,y0,x1,y1){
    drawLine(cpLine,null,x0,y0,x1,y1);

    if( p.u>0 ) drawUpArrow(p,tx.rowinfo[p.u-tx.iTopRow],p.fg,p.id);
    if( p.sb>0 ) drawDotted(p,tx.rowinfo[p.sb-tx.iTopRow],p.fg,p.id);
    var cls = node.cls;
    if( p.hasOwnProperty('mi') && p.mi.length ) cls += " merge";
    if( p.f&1 ) cls += " leaf";
    var n = drawBox(cls,p.bg,p.x,p.y);
    n.id = "tln"+p.id;
    addToolTip(n,p.id)
    n.onclick = clickOnNode;
    n.style.zIndex = 10;
    if( !tx.omitDescenders ){
      if( p.u==0 ){
        if( p.hasOwnProperty('mo') && p.r==p.mo ){
          var ix = p.hasOwnProperty('cu') ? p.cu : p.mu;
          var top = tx.rowinfo[ix-tx.iTopRow]
          drawUpArrow(p,{x: p.x, y: top.y-node.h}, p.fg, p.id);
        }else if( p.y>100 ){
          drawUpArrow(p,{x: p.x, y: p.y-50}, p.fg, p.id);
        }else{
          drawUpArrow(p,{x: p.x, y: 0},p.fg, p.id);
        }
      }
      if( p.hasOwnProperty('d') ){
        if( p.y + 150 >= btm ){
          drawUpArrow({x: p.x, y: btm - node.h/2},p,p.fg,p.id);
        }else{
          drawUpArrow({x: p.x, y: p.y+50},p,p.fg,p.id);
          drawDotted({x: p.x, y: p.y+63},{x: p.x, y: p.y+50-node.h/2},p.fg,p.id);
        }
      }
    }
    if( p.hasOwnProperty('mo') ){
      var x0 = p.x + node.w/2;
      var x1 = p.mo*railPitch + node.w/2;
      var u = tx.rowinfo[p.mu-tx.iTopRow];

        location.href=tx.baseUrl + "/fdiff?v1="+selRow.h+"&v2="+p.h
      }else{
        location.href=tx.baseUrl + "/vdiff?from="+selRow.h+"&to="+p.h
      }
    }
  }
  function tooltipEnter(e){
    var ix = this.getAttribute("data-ix")
    tooltipObj.textContent = tx.rowinfo[ix].br
    tooltipObj.style.display = "inline"
    tooltipObj.style.position = "absolute"
    var x = e.x + 4 + window.pageXOffset
    tooltipObj.style.left = x+"px"
    var y = e.y + window.pageYOffset - tooltipObj.clientHeight - 4
    tooltipObj.style.top = y+"px"
    tooltipObj.style.visibility = "visible"
  }
  function tooltipClick(e){
    var ix = this.getAttribute("data-ix")
    var br = tx.rowinfo[ix].br
    var dest = "/timeline?r=" + encodeURIComponent(br)
    tooltipObj.style.display = "none"
    window.location.href = tx.baseUrl + dest
  }
  function tooltipLeave(e){
    tooltipObj.style.display = "none"
  }
  function changeDisplay(selector,value){
    var x = document.getElementsByClassName(selector);
    var n = x.length;
    for(var i=0; i<n; i++) {x[i].style.display = value;}