raster_global_human_settlement.R

#idée : https://pudding.cool/2018/12/3d-cities-story/index.html
# how to https://docs.google.com/document/d/1Us_1QBHShdMe8-laKhGh_mjkXxOw-74-9mxJAx_DvKE/edit


# GHS population grid 2015 aux 250m téléchargé ici
#https://ghslsys.jrc.ec.europa.eu/datasets.php#2016public
# alternative à 100m vs 100 m ,world pop , mais pas  canada :A http://www.worldpop.org.uk/data/get_data/


# comment importer un raster- https://geocompr.robinlovelace.net/read-write.html
# raster rstudio leaflet https://rstudio.github.io/leaflet/raster.html
library(raster)
library(sf)
library(leaflet)
library(dplyr)
raster_filepath = system.file(here::here("Rapport/201808/data/raw/GHS_POP_GPW42015_GLOBE_R2015A_54009_250_v1_0", "GHS_POP_GPW42015_GLOBE_R2015A_54009_25_v1_0.tif"))

r = raster(here::here("Rapport/201808/data/raw/GHS_POP_GPW42015_GLOBE_R2015A_54009_250_v1_0", "GHS_POP_GPW42015_GLOBE_R2015A_54009_250_v1_0.tif"))
crs(r)


e <- as(extent(1000000,10000100,0,100), 'SpatialPolygons')

crs(e) <- crs(r)
r2 <- crop(r, e)


pal <- colorNumeric(c("red", "blue"), values(r2),
                    na.color = "transparent")

leaflet()%>%
  addRasterImage(r2, colors = pal) %>% 
  addLegend(pal = pal, values = values(r2))


r2
leaflet()%>%
  addRasterImage(r2, colors = pal, opacity = 0.8) %>%
  addLegend(pal = pal, values = values(r2),
            title = "dentity") %>%
   addTiles()





#https://stackoverflow.com/questions/33227182/how-to-set-use-ggplot2-to-map-a-raster

library(rgdal)
library(rasterVis)
library(RColorBrewer)

colr <- colorRampPalette(brewer.pal(11, 'RdYlBu'))


levelplot(r, 
          margin=FALSE,                       # suppress marginal graphics
          colorkey=list(
            space='bottom',                   # plot legend at bottom
            labels=list(at=-5:5, font=4)      # legend ticks and labels 
          ),    
          par.settings=list(
            axis.line=list(col='transparent') # suppress axes and legend outline
          ),
          scales=list(draw=FALSE),            # suppress axis labels
          col.regions=colr,                   # colour ramp
          at=seq(-5, 5, len=101)) 




levelplot(r2)