Droplines from points in 3D scatterplot?

Thanks for your response! It’s indeed possible to get the lines to show when I highlight the point with my cursor, but what I’d like is permanent lines from each point down to the x-y plane. For example, when using scatterplot3d(), this can be done by simply adding the line type=“h” like in this example:

library(scatterplot3d)
with(mtcars, {
  scatterplot3d(disp, wt, mpg,           # x y and z axis
                color="blue", pch=19,    # filled blue circles
                type="h",                # lines to the horizontal plane
                main="3-D Scatterplot Example",
                xlab="Displacement (cu. in.)",
                ylab="Weight (lb/1000)",
                zlab="Miles/(US) Gallon")
})

But plotly looks so much better and is more versatile than scatterplot3d()… Any suggestions? Thanks!