tiler

Create geographic and non-geographic map tiles

The tiler package provides a tile generator function for creating map tile sets for use with packages such as leaflet. In addition to generating map tiles based on a common raster layer source, it also handles the non-geographic edge case, producing map tiles from arbitrary images. These map tiles, which have a a non-geographic simple coordinate reference system, can also be used with leaflet when applying the simple CRS option.

Map tiles can be created from an input file with any of the following extensions: tif, grd and nc for spatial maps and png, jpg and bmp for basic images.

Motivation

This package helps R users who wish to create geographic and non-geographic map tiles easily and seamlessly with only a single line of R code. The intent is to do this with a package that has

• minimal heavy package dependencies.
• minimal extraneous general features and functions that do not have to do with tile generation.
• to create tiles without having to code directly in other software, interact directly with Python, or make calls at the command line; allowing the R user to remain comfortably within the familiar R environment.
• to support the creation on map tiles from raw images for users who wish to create non-standard maps, which may also be followed by georeferencing locations of interest in the simplified coordinate reference system of the map image.

Installation

Install tiler from CRAN with

install.packages("tiler")

Install the development version from GitHub with

# install.packages("remotes")
remotes::install_github("ropensci/tiler")

For non-geographic tiles, using a png file is recommended for quality and file size. jpg may yield a lower quality result, while a large, high resolution bmp file may have an enormous file size compared to png.

jpg and bmp are optionally supported by tiler. This means they are not installed and imported with tiler. It is assumed the user will provide png images. If using jpg or bmp and the packages jpeg or bmp are not installed, respectively, tile() will print a message to the console notifying of the required package installations.

System requirements

This package requires Python and the gdal library for Python. Windows users are recommended to install OSGeo4W as an easy way to obtain the required gdal support for Python in Windows. See tiler_options() or the package vignette for more information.

Please note that the tiler project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.