How to smooth out extreme elevations?

[Hedonical]

Hi everyone,

I am trying to create a 3D map of Colorado, but the large elevation gains are showing up as dramatic spikes instead of continuous terrain gradients. Does anyone know the best way to smooth out the terrain either in ray shader or by altering the data itself? Attached is my minimal viable code with the plot I am currently working with. Any thoughts or help is greatly appreciated and thank you so much ahead of time!

# install pacman if it is not installed
if (!"pacman" %in% rownames(installed.packages())){
  install.packages("pacman")
}

# load the pacman library
library("pacman")

# the default cran version of rayshader also has errors, so we need to load it straight from the github
options(repos = c(
    tylermorganwall = 'https://tylermorganwall.r-universe.dev',
    CRAN = 'https://cloud.r-project.org'))
if (!"rayshader" %in% rownames(installed.packages())){
  install.packages("rayshader")
}
library(rayshader)

# also load raster before dplyr, since they have name conflicts
if (!"raster" %in% rownames(installed.packages())){
  install.packages("raster")
}
library(raster, include.only = c("raster"))

pacman::p_load("tidyverse", "tidygeocoder", "ggplot2", "sf", 
               "sp", "elevatr", "rayshader")

# load the state dataset
state <- map_data("state")
# select colorado from the dataset
state <- subset(state, region == "colorado")

# convert our longitude and latitude to a polygon which elevatr can use
state <- state %>%
  st_as_sf(coords = c("long", "lat"), crs = 4326) %>%
  summarise(geometry = st_combine(geometry)) %>%
  st_cast(to = 'POLYGON')

# now use elevatr package to find the elevation data of colorado
co_elevation_data <- elevatr::get_elev_raster(state,
                                              z = 9)

# convert the raster to a raster matrix that rayshader can use
co_elevation_matrix <- raster_to_matrix(co_elevation_data)

# since raster objects are so large, it is wise to downsize it for changes until the final version is ready to save
co_elevation_matrix_small <- resize_matrix(co_elevation_matrix, scale =  .25)

# define our map
ThreeD_Map <- co_elevation_matrix_small %>%
  # shade our map according to height
  height_shade() %>%
  # add a 3d texture overlay
  # we need to transpose this matrix so it is the same size as the later shadows
  # potential solution is rayimage::render_reorient(matrix, transpose = TRUE)
  add_overlay(sphere_shade(co_elevation_matrix_small,
                           texture = "desert", 
                           zscale = 4,
                           colorintensity = 5),
              alphalayer = 0.5) %>%
  # add a shadow
  # lamb shade creates an array of the shadow intensities and their locations
  # shadowmap is a value 0 to 1, 0 means full darkness, 1 is full light
   add_shadow(hillshade = lamb_shade(co_elevation_matrix_small, 
                         zscale = 4)) %>%
  # add a shadow to valley ridges, helps improve depth
  add_shadow(ambient_shade(co_elevation_matrix_small), 0) %>%
  # add another shadow that better captures ridges and drainage networks
  add_shadow(texture_shade(co_elevation_matrix_small,
                           detail = 8/10,
                           contrast = 9,
                           brightness = 11),
             0.1) %>% 
  plot_3d(co_elevation_matrix_small)

render_snapshot()

[danilyanedo7]

The zscale parameter controls the exaggeration of the terrain's elevation. A lower zscale exaggerates elevation differences, while a higher zscale reduces it. In your code, you have zscale = 4 in sphere_shade and lamb_shade. Try increasing this value to smooth the elevation transitions. For example zscale = 30, and try different values of scale until you are okay with it.