r - ggplot2 3D Bar Plot -

i know sounds basic, have been searching literally more hour without success. i'm trying plot 3d bar plot in 'r' using 'ggplot2' package. dataframe looks this:

 x   y     z t1   5   high t1   2   low t1   4   med t2   8   high t2   1   low t2   3   med t3  50   high t3  12   med t3  35   low 

and want plot on it:

any more appreciated!!

as mentioned in comments, 3d plots aren't choice (when other options available) since tend give distorted/obscured view of data.

that said, here's how can plot data desired latticeextra:

d <- read.table(text=' x   y     z t1   5   high t1   2   low t1   4   med t2   8   high t2   1   low t2   3   med t3  50   high t3  12   med t3  35   low', header=true)  library(latticeextra)  cloud(y~x+z, d, panel.3d.cloud=panel.3dbars, col.facet='grey',        xbase=0.4, ybase=0.4, scales=list(arrows=false, col=1),        par.settings = list(axis.line = list(col = "transparent")))