Add a 2D plot or a legend in the background of an RGL window.

bgplot3d(expression, bg.color = getr3dDefaults("bg", "color"), ...)



Any plotting commands to produce a plot.


The color to use for the background.


Arguments to pass to the bg3d or legend function.


The bgplot3d function opens a png device and executes expression, producing a plot there. This plot is then used as a bitmap background for the current RGL subscene.

The legend3d function draws a standard 2D legend to the background of the current subscene by calling bgplot3d to open a device, and setting up a plot region there to fill the whole display.


The bgplot3d function invisibly returns the ID of the background object that was created, with attribute "value" holding the value returned when the expression was evaluated.

The legend3d function does similarly. The "value" attribute is the result of the call to legend. The scaling of the coordinates runs from 0 to 1 in X and Y.


Duncan Murdoch


Because the background plots are drawn as bitmaps, they do not resize very gracefully. It's best to size your window first, then draw the background at that size.

See also

bg3d for other background options.


x <- rnorm(100)
y <- rnorm(100)
z <- rnorm(100)
# Needs to be a bigger window than the default
par3d(windowRect = c(100, 100, 612, 612))
parent <- currentSubscene3d()
mfrow3d(2, 2)
plot3d(x, y, z)
next3d(reuse = FALSE)
bgplot3d(plot(y, z))
next3d(reuse = FALSE)
bgplot3d(plot(x, z))
next3d(reuse = FALSE)
legend3d("center", c("2D Points", "3D Points"), pch = c(1, 16))