function(event, g, contextB) {
      // prevents mouse drags from selecting page text.
      if (event.preventDefault) {
        event.preventDefault();  // Firefox, Chrome, etc.
      } else {
        event.returnValue = false;  // IE
        event.cancelBubble = true;
      }

      var canvasPos = utils.findPos(g.canvas_);
      contextB.px = canvasPos.x;
      contextB.py = canvasPos.y;
      contextB.dragStartX = utils.dragGetX_(event, contextB);
      contextB.dragStartY = utils.dragGetY_(event, contextB);
      contextB.cancelNextDblclick = false;
      contextB.tarp.cover();
    }
function(event, g, contextB) {
      
      if (event.preventDefault) {
        event.preventDefault();  
      } else {
        event.returnValue = false;  
        event.cancelBubble = true;
      }

      var canvasPos = utils.findPos(g.canvas_);
      contextB.px = canvasPos.x;
      contextB.py = canvasPos.y;
      contextB.dragStartX = utils.dragGetX_(event, contextB);
      contextB.dragStartY = utils.dragGetY_(event, contextB);
      contextB.cancelNextDblclick = false;
      contextB.tarp.cover();
    }
function ( event , g , contextB ) { // prevents mouse drags from selecting page text. if ( event . preventDefault ) { event . preventDefault ( ) ; // Firefox, Chrome, etc. } else { event . returnValue = false ; // IE event . cancelBubble = true ; } var canvasPos = utils . findPos ( g . canvas_ ) ; contextB . px = canvasPos . x ; contextB . py = canvasPos . y ; contextB . dragStartX = utils . dragGetX_ ( event , contextB ) ; contextB . dragStartY = utils . dragGetY_ ( event , contextB ) ; contextB . cancelNextDblclick = false ; contextB . tarp . cover ( ) ; }
contextB is the same thing as this context object but renamed.
contextB is the same thing as this context object but renamed .