[R] different colors for two wireframes in same plot

[marcg]

Hello R,

According to:

g <- expand.grid(x = 1:10, y = 5:15, gr = 1:2)
g$z <- log((g$x^g$g + g$y^2) * g$gr)
wireframe(z ~ x * y, data = g, groups = gr,
          scales = list(arrows = FALSE),
          drape = TRUE, colorkey = TRUE,
          screen = list(z = 30, x = -60))

i have two wireframes in one plot.

How could i change the color of the top - one to transparent (or only the grid). I want to give insight to the lower layer.

Could one make an if-statment like (if gr==1 do drape=F or color=none) if gr=2 do drape=T, colorkey=T)

Thanks for your help

Marc

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