This function allows the user to use the mouse to select a region in an RGL scene.

rgl.select3d(button = c("left", "middle", "right"),
             dev = cur3d(), subscene = currentSubscene3d(dev))
selectionFunction3d(proj, region = proj$region)



Which button to use for selection.

dev, subscene

The RGL device and subscene to work with


Button argument to pass to rgl.select3d


An object returned from rgl.projection containing details of the current projection.


Corners of a rectangular region in the display.


select3d and rgl.select3d select 3-dimensional regions by allowing the user to use a mouse to draw a rectangle showing the projection of the region onto the screen. They return a function which tests points for inclusion in the selected region.

selectionFunction3d constructs such a test function given coordinates and current transformation matrices.

If the scene is later moved or rotated, the selected region will remain the same, though no longer corresponding to a rectangle on the screen.


All of these return a function f(x, y, z) which tests whether each of the points (x, y, z) is in the selected region, returning a logical vector. This function accepts input in a wide variety of formats as it uses xyz.coords

to interpret its parameters.


Ming Chen / Duncan Murdoch


# Allow the user to select some points, and then redraw them
# in a different color

if (interactive()) {
 x <- rnorm(1000)
 y <- rnorm(1000)
 z <- rnorm(1000)
 points3d(x, y, z)
 f <- select3d()
 if (!is.null(f)) {
   keep <- f(x, y, z)
   points3d(x[keep], y[keep], z[keep], color = 'red')
   points3d(x[!keep], y[!keep], z[!keep])