Dimming of unselected points by both plotly and crosstalk makes points progressively fade away.

When I use crosstalk, selecting a rectangle multiple times causes other points to progressively dim away.

remotes::install_github("plotly/plotly.R")

library(plotly)

shared_data <- highlight_key(mtcars)
p <- ggplot(shared_data)+aes(cyl, mpg)+geom_point()

# Unselected points progressively fade as multiple selections are made
ggplotly(p) |>
    highlight(on="plotly_selected",off="plotly_deselect")

I suspect this is some strange interaction between the usual dimming of unselected points by plotly and the dimming of unselected points via the crosstalk selection. A workaround that seems to fix the problem is to disable the usual plotly dimming, so the only dimming of points is done via crosstalk.

# Workaround:
ggplotly(p) |>
    style(unselected=list(marker=list(opacity=1))) |>
    highlight(on="plotly_selected",off="plotly_deselect")

PS I'm very excited by the possibilties crosstalk offers. I had a wow moment when I realised it worked with GGally::ggpairs.

Inizia con l’esempio riproducibile in R che usa highlight_key(), ggplot(), ggplotly() e highlight() con plotly_selected. Selezioni rettangolari ripetute non dovrebbero rendere progressivamente più scuri i punti non selezionati e il workaround style(unselected=list(marker=list(opacity=1))) non dovrebbe più essere necessario.