This function takes a latitude/longitude coordinate pair alongside a desired
distance to map and retrieves USGS (and optionally ESRI) map data, converts
said data into matrices, and runs the data through rayshader using
sensible defaults in order to return a 2D shaded map relief. It requires a
functioning internet connection in order to retrieve data.
automap(
lat = NULL,
lng = NULL,
distance = 10,
method = c("2d", "3d"),
img.width = 600,
img.height = 600,
overlay = NULL,
z = 9,
overlay.alpha = 0.75,
colorscale = "imhof4",
color.intensity = 1,
max.darken = 0.5,
sun.angle = 315,
sun.altitude = 45,
water.cutoff = 0.999,
water.min.area = length(heightmap)/400,
water.max.height = NULL,
solid = TRUE,
shadow = TRUE,
water = FALSE,
waterdepth = 0,
theta = 45,
phi = 45,
fov = 0,
zoom = 1,
save.file = c(FALSE, "tif", "png", TRUE),
from.file = c(FALSE, "tif", "png", TRUE),
tif.filename = NULL,
png.filename = NULL,
dist.unit = c("km", "miles", "m", "ft"),
coord.unit = c("degrees", "radians"),
sr_bbox = 4326,
sr_image = 4326,
print.map = TRUE
)The latitude for the map's centroid, in decimal degrees or radians.
The longitude for the map's centroid, in decimal degrees or radians.
The distance between the centroid and any corner of the (square) output map to include.
Should a 2d or 3d plot be produced?
Image width, in pixels
Image height, in pixels
ESRI overlay map to include, if any -- see
get_image_overlay for list of options. If specifying
a local file with from.file, any non NULL value will add your
local file as an overlay.
zscale, passed to various rayshader functions. Defined as the ratio between the x and y spacing (which are assumed to be equal) and the z axis. For contiguous United States, USGS data is generally available at a ~9 meter spacing, with elevation provided in meter increments, resulting in a z value of 9 returning roughly representative maps; decrease this value to exaggerate elevation features.
Alpha value for the optional overlay layer.
Color scale for land and water elements. If a vector of length 1, the same color scale will be applied for both land and water. If greater than length 1, values named "water" or "watercolor" will be used for water coloring, while "land" or "landcolor" will be used for land.
Intensity of color mapping -- higher values result in more intense colors.
Passed to add_shadow. The lower
limit for how much the image will be darkened. 0 is completely black, 1 means
the shadow map will have no effect.
Angle around the matrix from which lights originate. Values line up with compass directions -- so 0 is directly North, while the default 315 places the sun in the Northwest.
Angle in degrees from horizon from which light originates. Bounded [0, 90].
Passed to detect_water. Defined
therein as the lower limit of the z-component of the unit normal vector to
be classified as water.
Passed to detect_water. The
minimum possible area to consider a body of water.
Passed to detect_water. If
provided, the maximum height a point can be classified water.
Logical -- should the output be rendered as a solid
(TRUE) or just a surface (FALSE)?
Logical -- should shadows be rendered?
Logical -- should water be rendered?
Water level.
Rotation around z axis.
Azimuth angle.
Field of view angle.
Zoom factor.
Should the heightmap (= "tif"), overlay
(= "png"), or both (= TRUE) be saved? Default FALSE
saves neither.
Should the map be built from local .tif
and .png files, rather than downloaded data? Accepts logical
FALSE (no local files used) and TRUE (local files used for both
height maps and textures, if requested), as well as strings tif
(only use height map, redownload PNG) and png (only use texture,
redownload tif). Overrides save arguments if local files are used.
If save.tif is TRUE, filename to save the
.tif height map to. If from.file is TRUE, filename to
load the height map from.
If save.png is TRUE, filename to save the
.png texture to. If from.file is TRUE, filename to
load the texture from.
Units for the distance argument. All units are converted to kilometers, with some errors in the transition due to floating point arithmetic -- so if high accuracy is needed, convert units to kilometers beforehand.
Units for latitude and longitude, in either decimal degrees or radians.
Spatial reference code (ISO 19111) for bounding box
Spatial reference code (ISO 19111) for image
Logical -- should the output map be printed?
A rayshader map object, by default printed and returned invisibly.
Archuleta, C.M., Constance, E.W., Arundel, S.T., Lowe, A.J., Mantey, K.S., and Phillips, L.A., 2017, The National Map seamless digital elevation model specifications: U.S. Geological Survey Techniques and Methods, book 11, chap. B9, 39 p., https://doi.org/10.3133/tm11B9
# NOT RUN {
automap(44.121268, -73.903734)
automap(44.121268, -73.903734, overlay = "World_Imagery")
automap(44.121268, -73.903734, overlay = "World_Imagery", method = "3d")
# }
# NOT RUN {
# }
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