Package 'ridges'

Bounding box of Wilder Kaiser

Description

A dataset containing the bounding box coordinates of the Wilder Kaiser mountain range.

Usage

bb_wilder_kaiser

Format

A numeric vector with 4 elements:

xmin

Minimum longitude

ymin

Minimum latitude

xmax

Maximum longitude

ymax

Maximum latitude

Source

OpenStreetMap data

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Calculate ridgeline data from elevation

Description

Takes elevation data and calculates the data needed for plotting ridgelines by sampling the elevation at regular y-intervals. You will only need this function if you want to create your own custom plots from the ground up.

Usage

calculate_ridgelines(elevation = NULL, n_lines = 30)

Arguments

elevation	A raster object containing elevation data, or NULL to use last elevation
n_lines	Number of ridgelines to calculate

Value

A data frame containing the ridgeline data with columns x, y, elevation, and group

See Also

plot_ridgelines

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Draw a bounding box on an interactive map in a web browser

Description

Opens an interactive map interface in your web browser where you can draw a rectangular bounding box to select an area of interest. Use the rectangle tool in the top-right corner to draw the box, then click 'Submit' to return the selection.

Usage

draw_bb(start_place_name = NULL, terrain = TRUE, provider = NULL)

Arguments

start_place_name	Optional address or place name to initially center the map on. This helps you quickly navigate to your area of interest.
terrain	Logical, whether to use OpenTopoMap tiles (default: TRUE)
provider	Optional custom tile provider. If specified, overrides the terrain parameter. See leaflet::providers for available providers.

Value

A bounding box object (sf::bbox) that can be used with get_elevation()

Examples

## Not run: 
# Open map centered on default location
bb <- draw_bb()

# Open map centered on a specific location
bb_innsbruck <- draw_bb("Innsbruck, Austria")

# Use the returned bounding box to get elevation data
elevation <- get_elevation(bb_innsbruck)

## End(Not run)
#

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Elevation data of Wilder Kaiser

Description

A dataset containing elevation data for the Wilder Kaiser mountain range.

Usage

ele_wilder_kaiser

Format

A raster object containing elevation data

Source

SRTM elevation data

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Export individual SVG files for each ridgeline

Description

Creates separate SVG files for each ridgeline slice, maintaining the same scaling and proportions as plot_ridgelines().

Usage

export_ridgeline_svgs(
  elevation = NULL,
  output_dir = "export",
  n_lines = 30,
  scale_factor = 10,
  line_color = "black",
  fill_color = NULL,
  linewidth = 0.5,
  width = 800,
  height = 200,
  closed = TRUE
)

Arguments

elevation	A raster object containing elevation data, as returned by get_elevation()
output_dir	Directory where SVG files will be saved (default: "export")
n_lines	Number of ridgelines to generate (default: 30)
scale_factor	Scaling factor for the height of ridgelines (default: 10)
line_color	Color of the ridgelines (default: "black")
fill_color	Color to fill closed shapes (default: same as line_color). Only used when closed = TRUE
linewidth	Width of the ridgelines (default: 0.5)
width	SVG width in pixels (default: 800)
height	SVG height in pixels (default: 200)
closed	Logical; if TRUE, creates closed shapes by adding a baseline (default: FALSE)

Value

Invisibly returns the paths to the created SVG files

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Get elevation data for a bounding box

Description

Retrieves elevation data for a specified geographic area using the elevatr package. The data is returned as a raster object that can be used with the plotting functions in this package.

Usage

get_elevation(bb = NULL, z = 9)

Arguments

bb	A bounding box object (sf::bbox) or NULL to use the last drawn bounding box
z	Zoom level for elevation data (1-14, higher means more detail). Default is 9, which provides a good balance between detail and download size.

Value

A raster object containing elevation data

Examples

# Using the included Wilder Kaiser bounding box
elevation <- get_elevation(bb_wilder_kaiser)
plot_elevation()

# Using a higher zoom level for more detail
detailed_elevation <- get_elevation(bb_wilder_kaiser, z = 12)
plot_elevation()

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Plot elevation data as contour lines

Description

Creates a visualization of elevation data using contour lines. This function provides a way to visualize terrain elevation changes through isolines.

Usage

plot_contours(
  elevation = NULL,
  interval = 100,
  line_color = "black",
  linewidth = 0.25,
  color_by_elevation = "none",
  low_color = "darkblue",
  high_color = "darkred",
  fill_alpha = 1
)

Arguments

elevation	A raster object containing elevation data, as returned by get_elevation()
interval	Elevation interval between contour lines in meters (default: 100)
line_color	Color of the contour lines (default: "black")
linewidth	Width of the contour lines (default: 0.25)
color_by_elevation	How to color elevation: "none", "lines", "fill", or "both" (default: "none")
low_color	Color for lowest elevations when coloring by elevation (default: "darkblue")
high_color	Color for highest elevations when coloring by elevation (default: "darkred")
fill_alpha	Alpha transparency for fill color (default: 1)

Value

A ggplot object that can be further customized using ggplot2 functions

Examples

# Create a basic contour plot
plot_contours(ele_wilder_kaiser)

# Customize contour interval and appearance
plot_contours(ele_wilder_kaiser,
  interval = 50,
  line_color = "darkred",
  linewidth = 0.1
)

# Color contours by elevation
plot_contours(ele_wilder_kaiser, color_by_elevation = "lines")

# Color fill by elevation
plot_contours(ele_wilder_kaiser, color_by_elevation = "fill")

# Color both lines and fill by elevation
plot_contours(ele_wilder_kaiser, color_by_elevation = "both")

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Plot elevation data as a heatmap

Description

Creates a heatmap visualization of elevation data. This function provides a quick way to visualize the terrain in your area of interest.

Usage

plot_elevation(elevation = NULL, low_color = "darkblue", high_color = "white")

Arguments

elevation	A raster object containing elevation data, as returned by get_elevation()
low_color	Color for lowest elevations (default: "darkblue")
high_color	Color for highest elevations (default: "white")

Value

A ggplot object that can be further customized using ggplot2 functions

Examples

# Create a basic elevation plot
plot_elevation(ele_wilder_kaiser)

# Customize colors
plot_elevation(ele_wilder_kaiser, low_color = "darkgreen", high_color = "yellow")

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Plot elevation data as ridgelines

Description

Creates topographical elevation ridgeline plots, inspired by the iconic Joy Division album cover.

Usage

plot_ridgelines(
  elevation = NULL,
  n_lines = 30,
  scale_factor = 10,
  line_color = "white",
  fill_color = "#FFFFFF1A",
  linewidth = 0.5,
  background_color = "black"
)

Arguments

elevation	A raster object containing elevation data, as returned by get_elevation()
n_lines	Number of ridgelines to draw (default: 30). More lines create a denser visualization but may increase plotting time.
scale_factor	Scaling factor for the height of ridgelines (default: 10). Higher values make the elevation differences more pronounced.
line_color	Color of the ridgelines (default: "white")
fill_color	Fill color below the lines (default: "#FFFFFF1A", semi-transparent white)
linewidth	Width of the ridgelines (default: 0.5)
background_color	Background color of the plot (default: "black")

Value

A ggplot object that can be further customized using ggplot2 functions

Examples

# Default style (white on black)
plot_ridgelines(ele_wilder_kaiser)

# No fill, just lines
plot_ridgelines(
  ele_wilder_kaiser,
  fill_color = NA,
  scale_factor = 12
)

# Classic black on white style
plot_ridgelines(
  ele_wilder_kaiser,
  line_color = "#000000",
  fill_color = "white",
  background_color = "white",
  scale_factor = 8
)

# Get creative!
plot_ridgelines(
  ele_wilder_kaiser,
  n_lines = 35,
  line_color = "#FF4081",
  fill_color = "#FF408133",
  background_color = "#1A237E"
)

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