dynamic visualisation of maps with leaflet and shiny

[adokter]

Suggestion to introduce new ppi method mapview(), which mirrors map() but allows users to pan and zoom. This is quite easily implemented with leaflet and shiny

Here an example to plot a ppi object (named ppi_int) which plots

• radar stations with metadata pop-up
• day/night terminator
• animal density and legend

# plot data using leaflet:
library(viridis)
library(leaflet)
library(shiny)
library(htmltools)
load("~/git/mosaic_aws/basemap.RData")
r <- raster(ppi_int$data)
pal <- colorNumeric("viridis",c(0,7),
                    na.color = "transparent")
previewColors(pal,seq(0,7))
leaflet() %>%
  # Base groups
  addTiles(group = "OSM (default)") %>%
  addProviderTiles(providers$Stamen.Toner, group = "Toner") %>%
  addProviderTiles(providers$Stamen.TonerLite, group = "Toner Lite") %>%
  addRasterImage(r, colors = pal, opacity = 0.8, group="VID") %>%
  addTerminator(time=grid[i], group="daylight") %>%
  addLayersControl(
    baseGroups = c("OSM (default)", "Toner", "Toner Lite"),
    overlayGroups = c("VID","daylight","radars", "legend"),
    options = layersControlOptions(collapsed = FALSE)) %>%
  hideGroup("daylight") %>%
  hideGroup("radars") %>%
  addMarkers(~lon, ~lat, data=radarInfo, popup = ~paste(sep= "<br/>", paste("radar: ",radar), paste("height: ",height), paste("antenna: ",antenna)), group="radars") %>%
  addLegend(pal = pal, values = c(0,7), title = "log(VID)", group="legend")

[adokter]

[bart1]

A quick note here, I developed starsTileServer to do this (https://gitlab.com/bartk/starsTileServer/). It might be slightly more complex but can produce more scalable results the addRasterImage functions