stat-density2d - stat_density2d_filled: possible to assign own density?

Question

When plotting with stat_density in ggplot:

# Create the KDE surface
kde <- ggplot(data = db) +
  stat_density2d_filled(
    data = as.data.frame(st_coordinates(db)), 
    aes(x = X, y = Y, alpha = ..level..),
    n = 16
  ) +
  scale_color_viridis_c() +
  theme_bw()

Is there a possibility to use my own density computed elsewhere (outside the stat_density2d function)?