docs: function(from, to, styles, ctx){
  
              var x = from.x
                  ,y = from.y
                  ;
  
              ctx = ctx || this.ctx;
  
              ctx.beginPath();
              this.setStyle( styles, ctx );
  
              ctx.moveTo(x, y);
  
              x = to.x;
              y = to.y;
  
              ctx.lineTo(x, y);
  
              ctx.stroke();
              ctx.fill();
          }