R6Map | R Documentation |
Create interactive visualizations of spatial EE objects
(ee$Geometry, ee$Image, ee$Feature, and ee$FeatureCollection)
using leaflet
.
R6Map
uses the Earth Engine method
getMapId to fetch and return an ID dictionary used to create
layers in a leaflet
object. Users can specify visualization
parameters to Map$addLayer by using the visParams argument. Each Earth
Engine spatial object has a specific format. For
ee$Image
, the
parameters available are:
Parameter | Description | Type |
bands | Comma-delimited list of three band (RGB) | list |
min | Value(s) to map to 0 | number or list of three numbers, one for each band |
max | Value(s) to map to 1 | number or list of three numbers, one for each band |
gain | Value(s) by which to multiply each pixel value | number or list of three numbers, one for each band |
bias | Value(s) to add to each Digital Number value | number or list of three numbers, one for each band |
gamma | Gamma correction factor(s) | number or list of three numbers, one for each band |
palette | List of CSS-style color strings (single-band only) | comma-separated list of hex strings |
opacity | The opacity of the layer (from 0 to 1) | number |
If you add an ee$Image
to Map$addLayer without any additional
parameters. By default it assigns the first three bands to red,
green, and blue bands, respectively. The default stretch is based on the
min-max range. On the other hand, the available parameters for
ee$Geometry
, ee$Feature
, and ee$FeatureCollection
are:
color: A hex string in the format RRGGBB specifying the color to use for drawing the features. By default #000000.
pointRadius: The radius of the point markers. By default 3.
strokeWidth: The width of lines and polygon borders. By default 3.
Object of class leaflet
and EarthEngineMap
, with the
following extra parameters: tokens, name, opacity, shown, min, max, palette,
position, and legend. Use the $ method to retrieve the data (e.g., m$rgee$min).
lon
The longitude of the center, in degrees.
lat
The latitude of the center, in degrees.
zoom
The zoom level, from 1 to 24.
save_maps
Should R6Map
save the previous maps?. If TRUE, Map
will work in an OOP style. Otherwise it will be a functional programming
style.
previous_map_left
Container on maps in the left side.
previous_map_right
Container on maps in the right side.
new()
Constructor of R6Map.
R6Map$new(lon = 0, lat = 0, zoom = 1, save_maps = TRUE)
lon
The longitude of the center, in degrees. By default -76.942478.
lat
The latitude of the center, in degrees. By default -12.172116.
zoom
The zoom level, from 1 to 24. By default 18.
save_maps
Should R6Map
save previous maps?.
A new EarthEngineMap
object.
reset()
Reset to initial arguments.
R6Map$reset(lon = 0, lat = 0, zoom = 1, save_maps = TRUE)
lon
The longitude of the center, in degrees. By default -76.942478.
lat
The latitude of the center, in degrees. By default -12.172116.
zoom
The zoom level, from 1 to 24. By default 18.
save_maps
Should R6Map
save previous maps?.
A new EarthEngineMap
object.
\dontrun{ library(rgee) ee_Initialize() # Load an Image image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318") # Create Map <- R6Map$new() Map$centerObject(image) # Simple display: Map just will Map$addLayer( eeObject = image, visParams = list(min=0, max = 10000, bands = c("B4", "B3", "B2")), name = "l8_01" ) Map # display map Map$reset() # Reset arguments Map }
print()
Display a EarthEngineMap
object.
R6Map$print()
An EarthEngineMap
object.
setCenter()
Centers the map view at the given coordinates with the given zoom level. If no zoom level is provided, it uses 10 by default.
R6Map$setCenter(lon = 0, lat = 0, zoom = 10)
lon
The longitude of the center, in degrees. By default -76.942478.
lat
The latitude of the center, in degrees. By default -12.172116.
zoom
The zoom level, from 1 to 24. By default 18.
No return value, called to set initial coordinates and zoom.
\dontrun{ library(rgee) ee_Initialize() Map <- R6Map$new() Map$setCenter(lon = -76, lat = 0, zoom = 5) Map # Map$lat # Map$lon # Map$zoom }
setZoom()
Sets the zoom level of the map.
R6Map$setZoom(zoom = 10)
zoom
The zoom level, from 1 to 24. By default 10.
No return value, called to set zoom.
\dontrun{ library(rgee) ee_Initialize() Map <- R6Map$new() Map$setZoom(zoom = 4) Map # Map$lat # Map$lon # Map$zoom }
centerObject()
Centers the map view on a given object. If no zoom level is provided, it will be predicted according to the bounds of the Earth Engine object specified.
R6Map$centerObject( eeObject, zoom = NULL, maxError = ee$ErrorMargin(1), titiler_server = "https://api.cogeo.xyz/" )
eeObject
Earth Engine spatial object.
zoom
The zoom level, from 1 to 24. By default NULL.
maxError
Max error when input image must be reprojected to an explicitly requested result projection or geodesic state.
titiler_server
TiTiler endpoint. Defaults to "https://api.cogeo.xyz/".
No return value, called to set zoom.
\dontrun{ library(rgee) ee_Initialize() Map <- R6Map$new() image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318") Map$centerObject(image) Map }
addLayer()
Adds a given Earth Engine spatial object to the map as a layer
R6Map$addLayer( eeObject, visParams = NULL, name = NULL, shown = TRUE, opacity = 1, position = NULL, titiler_viz_convert = TRUE, titiler_server = "https://api.cogeo.xyz/" )
eeObject
The Earth Engine spatial object to display in the interactive map.
visParams
List of parameters for visualization. See details.
name
The name of layers.
shown
A flag indicating whether layers should be on by default.
opacity
The layer's opacity is represented as a number between 0 and 1. Defaults to 1.
position
Character. Activate panel creation. If "left" the map will be displayed in the left panel. Otherwise, if it is "right" the map will be displayed in the right panel. By default NULL (No panel will be created).
titiler_viz_convert
Logical. If it is TRUE, Map$addLayer will transform the visParams to titiler style. Ignored if eeObject is not a COG file.
titiler_server
TiTiler endpoint. Defaults to "https://api.cogeo.xyz/".
An EarthEngineMap
object.
\dontrun{ library(rgee) ee_Initialize() # Load an Image image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318") # Create Map <- R6Map$new() Map$centerObject(image) # Simple display: Map just will Map$addLayer( eeObject = image, visParams = list(min=0, max = 10000, bands = c("B4", "B3", "B2")), name = "l8_01" ) Map$addLayer( eeObject = image, visParams = list(min=0, max = 20000, bands = c("B4", "B3", "B2")), name = "l8_02" ) # Simple display: Map just will (if the position is not specified it will # be saved on the right side) Map$reset() # Reset Map to the initial arguments. Map$centerObject(image) Map$addLayer( eeObject = image, visParams = list(min=0, max=10000, bands = c("B4", "B3", "B2")), name = "l8_left", position = "left" ) Map$addLayer( eeObject = image, visParams = list(min=0, max=20000, bands = c("B4", "B3", "B2")), name = "l8_right" ) Map$reset() }
addLayers()
Adds a given ee$ImageCollection to the map as multiple layers.
R6Map$addLayers( eeObject, visParams = NULL, nmax = 5, name = NULL, shown = TRUE, position = NULL, opacity = 1 )
eeObject
ee$ImageCollection to display in the interactive map.
visParams
List of parameters for visualization. See details.
nmax
Numeric. The maximum number of images to display. By default 5.
name
The name of layers.
shown
A flag indicating whether layers should be on by default.
position
Character. Activate panel creation. If "left" the map will be displayed in the left panel. Otherwise, if it is "right" the map will be displayed in the right panel. By default NULL (No panel will be created).
opacity
The layer's opacity is represented as a number between 0 and 1. Defaults to 1.
A EarthEngineMap
object.
\dontrun{ library(sf) library(rgee) ee_Initialize() Map <- R6Map$new() nc <- st_read(system.file("shape/nc.shp", package = "sf")) %>% st_transform(4326) %>% sf_as_ee() ee_s2 <- ee$ImageCollection("COPERNICUS/S2")$ filterDate("2016-01-01", "2016-01-31")$ filterBounds(nc) ee_s2 <- ee$ImageCollection(ee_s2$toList(2)) Map$centerObject(nc$geometry()) Map$addLayers(eeObject = ee_s2,position = "right") # digging up the metadata Map$previous_map_right$rgee$tokens Map$reset() }
addLegend()
Adds a color legend to an EarthEngineMap.
R6Map$addLegend( visParams, name = "Legend", position = c("bottomright", "topright", "bottomleft", "topleft"), color_mapping = "numeric", opacity = 1, ... )
visParams
List of parameters for visualization.
name
The title of the legend.
position
Character. The position of the legend. By default bottomright.
color_mapping
Map data values (numeric or factor/character) to colors according to a given palette. Use "numeric" ("discrete") for continuous (categorical) data. For display characters use "character" and add to visParams the element "values" containing the desired character names.
opacity
The legend's opacity is represented as a number between 0 and 1. Defaults to 1.
...
Extra legend creator arguments. See addLegend.
A EarthEngineMap
object.
\dontrun{ library(leaflet) library(rgee) ee_Initialize() Map$reset() # Load MODIS ImageCollection imgcol <- ee$ImageCollection$Dataset$MODIS_006_MOD13Q1 # Parameters for visualization labels <- c("good", "marginal", "snow", "cloud") cols <- c("#999999", "#00BFC4", "#F8766D", "#C77CFF") vis_qc <- list(min = 0, max = 3, palette = cols, bands = "SummaryQA", values = labels) # Create interactive map m_qc <- Map$addLayer(imgcol$median(), vis_qc, "QC") # continous palette Map$addLegend(vis_qc) # categorical palette Map$addLegend(vis_qc, name = "Legend1", color_mapping = "discrete") # character palette Map$addLegend(vis_qc, name = "Legend2", color_mapping = "character") }
clone()
The objects of this class are cloneable with this method.
R6Map$clone(deep = FALSE)
deep
Whether to make a deep clone.
## ------------------------------------------------
## Method `R6Map$reset`
## ------------------------------------------------
## Not run:
library(rgee)
ee_Initialize()
# Load an Image
image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318")
# Create
Map <- R6Map$new()
Map$centerObject(image)
# Simple display: Map just will
Map$addLayer(
eeObject = image,
visParams = list(min=0, max = 10000, bands = c("B4", "B3", "B2")),
name = "l8_01"
)
Map # display map
Map$reset() # Reset arguments
Map
## End(Not run)
## ------------------------------------------------
## Method `R6Map$setCenter`
## ------------------------------------------------
## Not run:
library(rgee)
ee_Initialize()
Map <- R6Map$new()
Map$setCenter(lon = -76, lat = 0, zoom = 5)
Map
# Map$lat
# Map$lon
# Map$zoom
## End(Not run)
## ------------------------------------------------
## Method `R6Map$setZoom`
## ------------------------------------------------
## Not run:
library(rgee)
ee_Initialize()
Map <- R6Map$new()
Map$setZoom(zoom = 4)
Map
# Map$lat
# Map$lon
# Map$zoom
## End(Not run)
## ------------------------------------------------
## Method `R6Map$centerObject`
## ------------------------------------------------
## Not run:
library(rgee)
ee_Initialize()
Map <- R6Map$new()
image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318")
Map$centerObject(image)
Map
## End(Not run)
## ------------------------------------------------
## Method `R6Map$addLayer`
## ------------------------------------------------
## Not run:
library(rgee)
ee_Initialize()
# Load an Image
image <- ee$Image("LANDSAT/LC08/C01/T1/LC08_044034_20140318")
# Create
Map <- R6Map$new()
Map$centerObject(image)
# Simple display: Map just will
Map$addLayer(
eeObject = image,
visParams = list(min=0, max = 10000, bands = c("B4", "B3", "B2")),
name = "l8_01"
)
Map$addLayer(
eeObject = image,
visParams = list(min=0, max = 20000, bands = c("B4", "B3", "B2")),
name = "l8_02"
)
# Simple display: Map just will (if the position is not specified it will
# be saved on the right side)
Map$reset() # Reset Map to the initial arguments.
Map$centerObject(image)
Map$addLayer(
eeObject = image,
visParams = list(min=0, max=10000, bands = c("B4", "B3", "B2")),
name = "l8_left",
position = "left"
)
Map$addLayer(
eeObject = image,
visParams = list(min=0, max=20000, bands = c("B4", "B3", "B2")),
name = "l8_right"
)
Map$reset()
## End(Not run)
## ------------------------------------------------
## Method `R6Map$addLayers`
## ------------------------------------------------
## Not run:
library(sf)
library(rgee)
ee_Initialize()
Map <- R6Map$new()
nc <- st_read(system.file("shape/nc.shp", package = "sf")) %>%
st_transform(4326) %>%
sf_as_ee()
ee_s2 <- ee$ImageCollection("COPERNICUS/S2")$
filterDate("2016-01-01", "2016-01-31")$
filterBounds(nc)
ee_s2 <- ee$ImageCollection(ee_s2$toList(2))
Map$centerObject(nc$geometry())
Map$addLayers(eeObject = ee_s2,position = "right")
# digging up the metadata
Map$previous_map_right$rgee$tokens
Map$reset()
## End(Not run)
## ------------------------------------------------
## Method `R6Map$addLegend`
## ------------------------------------------------
## Not run:
library(leaflet)
library(rgee)
ee_Initialize()
Map$reset()
# Load MODIS ImageCollection
imgcol <- ee$ImageCollection$Dataset$MODIS_006_MOD13Q1
# Parameters for visualization
labels <- c("good", "marginal", "snow", "cloud")
cols <- c("#999999", "#00BFC4", "#F8766D", "#C77CFF")
vis_qc <- list(min = 0, max = 3, palette = cols, bands = "SummaryQA", values = labels)
# Create interactive map
m_qc <- Map$addLayer(imgcol$median(), vis_qc, "QC")
# continous palette
Map$addLegend(vis_qc)
# categorical palette
Map$addLegend(vis_qc, name = "Legend1", color_mapping = "discrete")
# character palette
Map$addLegend(vis_qc, name = "Legend2", color_mapping = "character")
## End(Not run)
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