In mikey-harper/ggmapstyles: Integrates ggmap with additional Google Maps styles through SnazzyMaps

knitr::opts_chunk$set(
                      collapse = TRUE,
                      comment = "#>",
                      fig.path = "man/figures/README-",
                      echo = FALSE,
                      fig.align = "center",
                      out.width = "100%"
)

library(ggmap)
library(ggmapstyles)
library(tidyverse)
library(rvest)

options(scipen = 999)

ggmapstyles

---

knitr::include_graphics("ggmapstylesCover.png")

Overview

ggmapstyles is an R package which extends the ggmap package. This package simplifes the process of creating custom designs for Google Maps, and provides a range of tools for quickly loading themes from Snazzy Maps by simply copying a website URL.

# Counts how many styles have been released
countStyles <- 
  xml2::read_html("https://snazzymaps.com/press") %>%
  html_nodes(xpath = '//*[@class="figure-stat-value"]') %>%
  .[2] %>%
  str_replace('<div class="figure-stat-value">', "") %>%
  str_replace('\n</div>', "") %>%
  str_replace(",", "") %>%
  as.numeric()

# Find the nearest thousand of the value
countStyles <- (floor(countStyles/1000)*1000)

Say goodbye to the standard Google Maps background, and easily choose from one of over r countStyles custom themes! If you cannot find a style you like, it is easy to sign up and create your own customised layers.

This package is still in development. If you find any errors, or have any suggestions for improvements, please open an Issue.

A selection of some of the styles available are shown below:

# List maps to include
urls <- c("https://snazzymaps.com/style/35/avocado-world",
          "https://snazzymaps.com/style/98/purple-rain",
          "https://snazzymaps.com/style/84/pastel-tones",
          "https://snazzymaps.com/style/64/old-dry-mud",
          "https://snazzymaps.com/style/8097/wy",
          "https://snazzymaps.com/style/23/bates-green",
          "https://snazzymaps.com/style/127403/no-label-bright-colors",
          "https://snazzymaps.com/style/83/muted-blue",
          "https://snazzymaps.com/style/127403/no-label-bright-colors",
          "https://snazzymaps.com/style/14/vintage",
          "https://snazzymaps.com/style/68/aqua",
          "https://snazzymaps.com/style/126378/vintage-old-golden-brown",
          "https://snazzymaps.com/style/72/transport-for-london",
          "https://snazzymaps.com/style/6296/darkdetail",
          "https://snazzymaps.com/style/21/hopper",
          "https://snazzymaps.com/style/40/vitamin-c")

# Create Plot
plotGrid <-
  lapply(urls, function(x)
ggmap(get_snazzymap(center = "Southampton, UK", mapRef = x, maptype = "roadmap")) +
  annotate(geom = "label", x = -0.97, y = 50.64, 
           label = paste0("Style ID: ", basename(dirname(x))), 
           hjust = 1, vjust = 0, label.r = unit(0, "lines"), label.size = 0) +
  theme_void() +
  theme(plot.title = element_text(hjust = 0.5, margin = margin(0.5, 0, 0.5, 0, unit = "cm") ))
)

# Plot the results
gridExtra::grid.arrange(grobs = plotGrid, ncol = 4)

Installation

You can install the development version of the package through Github:

devtools::install_github("dr-harper/ggmapstyles")

Google recently changed their API requirements, so you will need to register with Google first. A useful guide is found in the ggmaps package: https://github.com/dkahle/ggmap

Usage

You can browse Snazzy Maps to find a style you like. A number of functions have been developed to simplify the usage of Snazzymaps within existing workflows.

The main function to use within the package is get_snazzymap. This is a wrapper of the get_googlemap function, with the style of the map being set by mapRef:

library(ggmapstyles)
basemap <- get_snazzymap("Southampton, UK", mapRef = "https://snazzymaps.com/style/83/muted-blue")
ggmap(basemap)

The mapRef parameter can accept the Snazzy Map reference in a number of different ways:

• Full URL: mapRef = "https://snazzymaps.com/style/83/muted-blue"
• ID & Name: mapRef = "83/muted-blue"
• ID: mapRef = 83

You can also supply additional arguments to the get_snazzymap function which are provided to get_googlemap. For example, the zoom can be changed as follows:

basemap <- get_snazzymap("Southampton, UK", mapRef = "98/purple-rain", zoom = 15)
ggmap(basemap)

It's useful to note that the maptype argument of get_googlemap still defaults to returning a terrain map. This may make the Snazzymaps styling look different from expected, and different from the appearance on the Snazzymaps site, where the default is a roadmap. This is mostly useful for styling terrain or roadmaps; some, but not all, styling will show up with hybrid maps as well.

# default: terrain
terrain <- ggmap(get_snazzymap("Southampton, UK", mapRef = "23/bates-green")) +
  ggtitle("Terrain")
roadmap <- ggmap(get_snazzymap("Southampton, UK", mapRef = "23/bates-green", maptype = "roadmap")) +
  ggtitle("Roadmap")
hybrid <- ggmap(get_snazzymap("Southampton, UK", mapRef = "23/bates-green", maptype = "hybrid")) +
  ggtitle("Hybrid")

gridExtra::grid.arrange(terrain, roadmap, hybrid, ncol = 3)

If you would rather use the style argument within the get_googlemap, you can create a formatted string using the ggmap_style_sm function:

style_string <- ggmap_style_sm("84/pastel-tones")
style_string

This string can then easily be reused within any other ggmap function which takes a style argument. This approach is recommended if you want to plot multiple maps with the same basemap:

plot1 <- ggmap(get_googlemap("Southampton, UK", style = style_string)) + labs(title = "Southampton")
plot2 <- ggmap(get_googlemap("London, UK", style = style_string)) + labs(title = "London")
plot3 <- ggmap(get_googlemap("Bristol, UK", style = style_string)) + labs(title = "Bristol")

gridExtra::grid.arrange(plot1, plot2, plot3, ncol = 3)

Cached Styles

16 map styles are supplied within the package. These can be accessed by using the map_styles() function, and the following styles are available:

knitr::kable(ggmapstyles::list_styles())

There are several ways you can use this function to refer to a style:

• By name: map_style("Blue Essence")
• By ID: map_style(ID = "40")
• Pick one style at random: map_style(random = TRUE): this also prints a message so that you know which style to reuse.

# search by name
map_style("Blue Essence")

# search by ID
map_style(ID = "40")

# Use directly within ggmap function
ggmap::get_googlemap("Southampton", style = map_style("apple-like"))

Additional Reading

This cheatsheet into ggmap is useful for picking up some of the basics of ggmap.

mikey-harper/ggmapstyles documentation built on July 21, 2019, 7 p.m.