Tour Layer Configuration

Mainly used in the 2D (or 1D) tour interactive layer configuration

l_layer_callback(target, layer, ...)

Arguments

target	either a `l_tour` object or a loon widget
layer	the layer need to be modified
...	some useful info for the layer configuration (i.e. tours, projections, etc)

Value

this callback function does not return any object. As the slider bar is scrolled, for the specified layer, the callback function will be fired and the layer will be configured.

Details

It is a S3 method. The object class is determined by the layer **label**

Examples

if(interactive() && requireNamespace("tourr")) {
  # 1D tour
  p <- l_tour(iris[, -5], tour = tourr::grand_tour(1L))
  # add layer density
  l <- l_layer(l_getPlots(p),
               stats::density(p['x']),
               label = "density")

  # as we scroll the bar, the density curve does not change
  # unless the following function is executed
  l_layer_callback.density <- function(target, layer, ...) {

      layer <- loon::l_create_handle(c(l_getPlots(target), layer))
      den <- stats::density(target['x'])

      loon::l_configure(layer,
                        x = den$x,
                        y = den$y)

      invisible()
  }
}