These are low level functions to set or get user-defined axis labelling callbacks in R.

rgl.setAxisCallback(axis, draw = NULL,
dev = cur3d(), subscene = currentSubscene3d(dev))
rgl.getAxisCallback(axis, dev = cur3d(), subscene = currentSubscene3d(dev))

## Arguments

axis

Which axis? Can be value from 1:3.

draw

The function to draw the axis. See Details below.

dev, subscene

The RGL device and subscene to work with.

## Details

This function only works if a bounding box decoration (set by bbox3d, for example) exists. When it tries to label the axis specified in rgl.setAxisCallback, it will call draw, which is assumed to be a function with header function(margin).

The margin argument will be a single string like "x++", indicating that RGL is drawing the x axis, and suggests putting it on the edge represented by the high values of the other two axes. The function may use par3d("bbox") to determine the current size of the bounding box and should draw an appropriate axis. See mtext3d for a discussion of drawing in the margins.

The box outlining the plot region will always be drawn, but can be made invisible by setting front = "cull", back = "cull" in the call to bbox3d.

## Value

Called for the side effect of setting the callback. The set function returns NULL invisibly.

setAxisCallbacks to work with rglwidget.

Duncan Murdoch

## Examples

datelabels <- local({

id <- 0
bbox <- NULL

function(margin) {
# Only need to redraw when the bbox changes
if (!identical(bbox, par3d("bbox"))) {
if (id > 0)
pop3d(id = id)
axis <- match(substr(margin, 1, 1), c("x", "y", "z"))
range <- as.Date(par3d("bbox")[2*axis + (-1):0],
origin = "1970-01-01")
where <- pretty(range)
where <- where[range[1] <= where & where <= range[2]]
id <<- mtext3d(format(where, format="%b %d"), margin, at = where, line = 1)
bbox <<- par3d("bbox")
}
}
})

# This doesn't work in WebGL displays

if (!in_pkgdown_example()) {
xyz <- cbind(Sys.Date() + rnorm(10, mean = 10),
rnorm(10), rnorm(10))
open3d()
# The default plots dates numerically:
plot3d(xyz, xlab = "Date", ylab = "y", zlab = "z")

rgl.setAxisCallback(1, datelabels)
# Repeat the data 5 days later
points3d(xyz + rep(c(5, 0, 0), each = 10))
# Make the plot square again
aspect3d(1,1,1)
}