# Elevation and GPS Data Visualisation

## Documentation for package ‘geoviz’ version 0.2.2

- DESCRIPTION file.
- User guides, package vignettes and other documentation.

## Help Pages

add_gps_to_rayshader | Adds a GPS trace to a 'rayshader' scene
crop_raster_square | Crops a raster and returns a smaller square raster
crop_raster_track | Crops a raster into a rectangle surrounding a set of lat long points
dplyr_data | .data to allow column name use in dplyr
drybrush | Simulates a dry brushing effect. Differs from elevation_transparency() in that colour is applied based on local altitude peaks, not across the whole raster
elevation_shade | Produces an elevation shaded image from a raster
elevation_transparency | Turns overlay images transparent based on altitude. Can be used to create an image overlay that will only apply to valleys, or only to hills.
example_igc | Returns an example IGC file using read_igc()
example_raster | Returns an example digital elevation model raster file()
get_slippy_map | Obtains and merges map tiles from various sources using the 'slippymath' package
ggslippy | Adds a layer created using slippy_overlay() or slippy_raster() to a 'ggplot2' chart
latlong_to_rayshader_coords | Converts WGS84 lat long points into 'rayshader' coordinates. Useful for adding arbitrary points and text to a 'rayshader' scene.
mapbox_dem | Gets Digital Elevation Model (DEM) data from 'mapbox'
mapzen_dem | Gets Digital Elevation Model (DEM) data from 'mapzen' via 'Amazon Public Datasets'
mosaic_files | Stitches together files into a single raster Requires a target directory of files that can be read with raster::raster(), e.g. .asc files, or a directory of .zip files containing these files
raster_zscale | Approximates the zscale of a raster Digital Elevation Model for 'rayshader'
read_igc | Load an IGC file
slippy_overlay | Creates an overlay image from 'Mapbox' or 'Stamen' Maps using the 'slippymath' package
slippy_raster | Creates a square raster centred on any lat long point, or a rectangular raster surrounding a set of lat long points from 'Mapbox', 'Mapzen' or 'Stamen' Maps using the 'slippymath' package