Select a rectangle in an RGL scene

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

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

Arguments

button

Which button to use for selection.

dev, subscene

The RGL device and subscene to work with

proj

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

region

Corners of a rectangular region in the display.

Details

select3d selects 3-dimensional regions by allowing the user to use a mouse to draw a rectangle showing the projection of the region onto the screen. It returns 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.

Value

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.

Author

Ming Chen / Duncan Murdoch

See also

selectpoints3d, locator

Examples

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

if (interactive() && !in_pkgdown_example()) {
 x <- rnorm(1000)
 y <- rnorm(1000)
 z <- rnorm(1000)
 open3d()
 points3d(x, y, z)
 f <- select3d()
 if (!is.null(f)) {
   keep <- f(x, y, z)
   pop3d()
   points3d(x[keep], y[keep], z[keep], color = 'red')
   points3d(x[!keep], y[!keep], z[!keep])
 }
}