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tmap (version 1.11)

tm_view: Options for the interactive tmap viewer

Description

Set the options for the interactive tmap viewer. Some of these options can also be set with tm_layout, since they are style dependent (e.g., the choice of basemaps). The function tm_view overrides these options when specified.

Usage

tm_view(alpha = NA, colorNA = NA, basemaps = NA, basemaps.alpha = NA,
  projection = 3857, symbol.size.fixed = FALSE, dot.size.fixed = TRUE,
  text.size.variable = FALSE, set.bounds = FALSE, set.view = NA,
  set.zoom.limits = NA, legend.position = c("right", "top"),
  control.position = c("left", "top"), popup.all.data = NULL,
  bg.overlay = NULL, bg.overlay.alpha = NULL)

Arguments

alpha

transparency (opacity) parameter applied to whole map. By default, it is set to 0.7 if basemaps are used, and 1 otherwise.

colorNA

default color for missing values in interactive mode. If the color of missing values is not defined in the layer functions (e.g. tm_fill), then the default color is taken from the na value of the aes.color argument in tm_layout. This colorNA argument (if not NA itself) overrides that default value. For interactive maps, it can be useful to set colorNA to NULL, which means transparent.

basemaps

vector of one or more names of baselayer maps, or a logical value. See http://leaflet-extras.github.io/leaflet-providers/preview. Also supports URL's for tile servers, such as "http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png". By default (NA), the choice of basemap(s) will be determined by the basemaps argument of tm_layout, which is style dependent. Use TRUE to select a large set of recommended basemaps. Use FALSE to omit basemap tiles. If a named vector is provided, the names are used in the layer control legend.

basemaps.alpha

transparency (opacity) value for the basemaps. Can be a vector of values, one for each basemap.

projection

projection. Either a EPSG number, or a leaflet_crs object created with leafletCRS. By default, the Web Mercator (3857) is used, since the vast majority of basemaps are rendered accordingly. Other standards are EPSG numbers 4326 (WGS84) and 3395 (Mercator). If set to 0, the projection of the master shape is used (see tm_shape) provided that a EPSG number can be extracted.

symbol.size.fixed

should symbol sizes be fixed while zooming?

dot.size.fixed

should dot sizes be fixed while zooming?

text.size.variable

should text size variables be allowed in view mode? By default FALSE, since in many applications, the main reason to vary text size is to prevent occlusion in plot mode, which is often not a problem in view mode due to the ability to zoom in.

set.bounds

logical that determines whether maximum bounds are set, or a numeric vector of four values that specify the lng1, lat1, lng2, and lat2 coordinates (see setMaxBounds).

set.view

numeric vector or three that determines the view: lng, lat, and zoom (see setView).

set.zoom.limits

numeric vector of two that set the minimum and maximum zoom levels (see tileOptions).

legend.position

Character vector of two values, specifing the position of the legend. Use "left" or "right" for the first value and "top" or "bottom" for the second value. It overrides the value of legend.position of tm_layout, unless set to NA.

control.position

Character vector of two values, specifing the position of the layer control UI. Use "left" or "right" for the first value and "top" or "bottom" for the second value.

popup.all.data

not used anymore. As of version 1.6, the popups are specified by the argument popup.vars in the layer functions tm_fill, tm_symbols, and tm_lines.

bg.overlay

not used anymore as of version 1.7. Instead of an overlay, a background color is set, which is determined by bg.color of tm_layout, which is style dependent.

bg.overlay.alpha

not used anymore as of version 1.7. Instead of an overlay, a background color is set. The trade-off between background and basemaps can now be set by basemaps.alpha

See Also

tmap_mode and vignette("tmap-modes")

Examples

Run this code
# NOT RUN {
# world choropleth/bubble map of the world
data(World, metro)
metro$growth <- (metro$pop2020 - metro$pop2010) / (metro$pop2010 * 10) * 100

map1 <- tm_shape(metro) +
	tm_bubbles("pop2010", col = "growth", 
		border.col = "black", border.alpha = .5, 
		style="fixed", breaks=c(-Inf, seq(0, 6, by=2), Inf),
		palette="-RdYlBu", contrast=1, 
		title.size="Metro population", 
		title.col="Growth rate (%)", id="name", 
		    popup.vars=c("pop2010", "pop2020", "growth")) + 
	tm_legend(outside=TRUE)

current.mode <- tmap_mode("plot")

# plot map
map1

# view map with default view options
tmap_mode("view")
map1

# view map with changed view options
map1 + tm_view(alpha = 1, basemaps = "Stamen.Watercolor")

# restore current mode
tmap_mode(current.mode)
# }

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