         chartArea.append("g")
             .attr("class", "axis")
             .attr("transform", "translate(#{margin.left}, #{margin.top+height-110})")
-            .call(@xAxis) 
+                .call(@xAxis) 
 
         chartArea.append("g")
             .attr("class", "axis")

            .attr("cx", Xm)
            .attr("cy", Ym)

        @line1 = @roofLine(-0.5, -0.5)
            .attr("x2", Xm)
            .attr("y2", Ym)

        @line2 = @roofLine(0.5, 0.5)
            .attr("x2", Xm)
            .attr("y2", Ym)


        x = Trans.X2x @pos.x
        y = Trans.fn x, plot.xm, plot.ym
        @limit =  Trans.y2Y y
        @bin = Math.floor((y+1)*20/2)  
 
    collision: -> @pos.y > @limit

