WaveTrend with Crosses [LazyBear]

//
// @author LazyBear
//
// If you use this code in its original/modified form, do drop me a note. 
//
study(title="WaveTrend with Crosses [LazyBear]", shorttitle="WT_CROSS_LB")
n1 = input(10, "Channel Length")
n2 = input(21, "Average Length")
obLevel1 = input(60, "Over Bought Level 1")
obLevel2 = input(53, "Over Bought Level 2")
osLevel1 = input(-60, "Over Sold Level 1")
osLevel2 = input(-53, "Over Sold Level 2")
 
ap = hlc3 
esa = ema(ap, n1)
d = ema(abs(ap - esa), n1)
ci = (ap - esa) / (0.015 * d)
tci = ema(ci, n2)
 
wt1 = tci
wt2 = sma(wt1,4)

plot(0, color=gray)
plot(obLevel1, color=red)
plot(osLevel1, color=green)
plot(obLevel2, color=red)
plot(osLevel2, color=green)

plot(wt1, color=green)
plot(wt2, color=red)
plot(wt1-wt2, color=blue, style=area, transp=80)
plot(cross(wt1, wt2) ? wt2 : na, color = black , style = circles, linewidth = 3)
plot(cross(wt1, wt2) ? wt2 : na, color = (wt2 - wt1 > 0 ? red : lime) , style = circles, linewidth = 2)
barcolor(cross(wt1, wt2) ? (wt2 - wt1 > 0 ? aqua : yellow) : na)