#30DayMapChallenge 2021 - Day 10 - Raster - 3D Kāpiti Island with rayshader

kapiti_bw.R

# Make a black and white elevation map of Kāpiti Island, New Zealand
# adapting https://github.com/AmitLevinson/30daymapchallenge/blob/main/2021/09_monochrome/monochrome.R
# for #30DayMapChallenge 2021 - Day 10 - Raster
#  -- David Friggens, November 2021

library(elevatr)
library(rayshader)
library(sf)
library(dplyr)

# Luckily the island is its own Statistical Area 2, & I have those from
# datafinder.stats.govt.nz
ki_outline <- 
  read_sf("statsnz/statistical-area-2-2021-clipped-generalised.gpkg") %>% 
  filter(SA22021_V1_00_NAME_ASCII == "Kapiti Island")
ki_outline <- 
  ki_outline %>% 
  st_transform(crs = 4326L) %>% 
  select(geom) %>% 
  st_cast("POLYGON") %>% 
  slice(4) # Just take the main island and ignore the pesky tiny ones

# Get elevation data
ki_raster <-
  get_elev_raster(
    locations = ki_outline,
    z = 12,
    clip = "locations")

# Convert to matrix for rayshader plotting
ki_matrix = raster_to_matrix(ki_raster)

# The biggest issue I had getting this working was figuring out that my island
# way up in the air was due to the zscale being too low
ki_matrix %>% 
  sphere_shade(texture = "bw") %>% 
  plot_3d(ki_matrix, zscale = 10, fov = 0, theta = 0, zoom = 0.9, phi = 45, windowsize = c(1000, 800))

render_snapshot("Day_10/Day_10_raster_kapiti",
                title_text = "K\u0101piti Island",
                title_offset = c(220,300),
                title_color = "black",
                title_size = 40,
                title_font = "Poppins",
                vignette = 0.1)