[R] question about cleaning up data labels on a plot3d plot

[LMH]

Hello,

I am rather unfamiliar with R but need a 3D plot for something I am working on.

I was able to generate a plot with the following,

library(rgl)
setwd("G:/shared_data/R_projects/3D_plot")
df <- read.table("R_input_3D_PCA-3_RI9_60.txt", header = TRUE)
plot3d(df$PCA_Axis1, df$PCA_Axis2, df$PCA_Axis3, col="blue", size=10)

My data is tab delimited and looks like,

num  PCA_Axis1   PCA_Axis2   PCA_Axis3
11   -0.672164   -0.83449    -1.06511
12   -1.23009    1.57928     -0.066808
42   2.80029     0.533236    -0.197187
60   2.25999     -0.233224   -0.00267827
67   1.82422     -0.840649   0.156681

There are a total of 60 rows.

Adding,

text3d(df, text=df$num)

displays my index value on the plot, but the numbers are very hard to read. It looks 
like the the labels are behind the points. Is there any way to clean this up some? I 
guess I could color the points white so I only see the numbers.

I also have 2 or three different sub groups within the data. Is there any way to have 
these different groups appear in different colors? I could create multiple 
data.frames if that would help. I am not sure you can display data from multiple 
frames on the same plot.

Suggestions would be appreciated,

LMH