Produce interactive visualization of time integrated footprint

stilt-footprint-map-example.r

#!/usr/bin/env Rscript

library(htmlwidgets)
library(leaflet)
library(raster)
library(viridis)

path <- 'example-footprint.nc'
footprint <- brick(path)
footprint
# class      : RasterBrick 
# dimensions : 300, 300, 90000, 6  (nrow, ncol, ncell, nlayers)
# resolution : 0.01, 0.01  (x, y)
# extent     : -114, -111, 39, 42  (xmin, xmax, ymin, ymax)
# crs        : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0 
# source     : /Users/benfasoli/Desktop/stilt/example-footprint.nc 
# names      : X1449684000, X1449687600, X1449691200, X1449694800, X1449698400, X1449702000 
# z-value    : 1449684000, 1449687600, 1449691200, 1449694800, 1449698400, 1449702000 
# varname    : foot 

footprint_timeint <- sum(footprint)

# Set zero footprint values to NA to hide from displaying
mask <- footprint_timeint == 0
footprint_timeint[mask] <- NA
# Uncomment to display entire domain
# footprint_timeint[mask] <- quantile(values(footprint_timeint), 0.01, na.rm = T)

# Log10 transform for visualizations
footprint_timeint_log10 <- log10(footprint_timeint)
footprint_timeint_log10
# class      : RasterLayer 
# dimensions : 46, 60, 2760  (nrow, ncol, ncell)
# resolution : 0.3, 0.3  (x, y)
# extent     : -123, -105, 33, 46.8  (xmin, xmax, ymin, ymax)
# crs        : +proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0 
# source     : memory
# names      : layer 
# values     : -8.396288, 0.1152478  (min, max)


# Leaflet legends default to what would normally be considered upside-down,
# where smallest value is at top and largest at bottom. Reverse the order and
# add back in the negative sign in the addLegend() call
footprint_timeint_log10 <- -footprint_timeint_log10

colors <- colorNumeric(viridis::viridis(256), 
                       domain = values(footprint_timeint_log10),
                       na.color = '#00000000', 
                       reverse = T)

map <- leaflet() %>%
  addProviderTiles('CartoDB.Positron') %>%
  addRasterImage(footprint_timeint_log10, opacity = 0.5, colors = colors) %>%
  addLegend(position = 'bottomright',
            pal = colors,
            values = values(footprint_timeint_log10),
            title = 'log10',
            labFormat = labelFormat(prefix = '-'))

saveWidget(map, 'example-map.html')
map