Draw only labels in the plotting region

NEWS.md

@@ -2,6 +2,9 @@
 ## New classes and methods
 * Add `export()` to create a Zip archive of all results in CSV format.
 
+## Internals
+* Compute the position and draw only the labels in the plotting region.
+
 # dimensio 0.9.0
 ## New classes and methods
 * Add `pcoa()` to compute principal coordinates analysis.

R/annotations.R

@@ -17,6 +17,8 @@
 #' @return
 #'  `label()` is called it for its side-effects: it results in a graphic
 #'  being displayed.
+#' @details
+#'  Only labels in the plotting region (given by `par("usr")`) will be drawn.
 #' @seealso [graphics::text()]
 #' @note
 #'  This function is modeled after [car::pointLabel()] (originally from the
@@ -34,6 +36,17 @@ label <- function(x, y = NULL, labels = seq_along(x$x),
   labels <- grDevices::as.graphicsAnnot(labels)
   if (length(labels) < length(x$x)) labels <- rep(labels, length(x$x))
 
+  ## Filter
+  xlim <- graphics::par("usr")[c(1, 2)]
+  ylim <- graphics::par("usr")[c(3, 4)]
+  x_filter <- x$x >= min(xlim) & x$x <= max(xlim)
+  y_filter <- x$y >= min(ylim) & x$y <= max(ylim)
+  xy_filter <- which(x_filter & y_filter)
+
+  x$x <- x$x[xy_filter]
+  x$y <- x$y[xy_filter]
+  labels <- labels[xy_filter]
+
   ## Compute label positions
   labs <- compute_labels(x = x$x, y = x$y, labels = labels)