ol_geom_point: OpenLayers Point Layer

In cemarks/ROpenLayers: Geo-visualization Using OperLayers and ArcGIS

OpenLayers Point Layer

Description

Function to create a points layer to add to an OpenLayers Map object.

Usage

ol_geom_point(point.obj, mapping = ol_aes(), name = NULL, df = NULL,
  toggle.control = FALSE, fill = "#00FF00", fill.opacity = 1,
  marker = "pin", size = 0.5, label = NULL, label.params = list(),
  tooltip = NULL, tooltip.params = list())

Arguments

point.obj	SpatialPointsDataframe, SpatialPoints, or a matrix containing columns of point longitudes and latitudes, respectively.
mapping	list created by ol_aes. Used for aestheic mapping.
name	character Layer name.
df	data.frame with same number of rows as point.obj coordinate matrix.
toggle.control	logical indicating whether this layer will have a visibility toggle.
fill	character color string, or vector of color strings. Used only if no fill aesthetic is provided in mapping
fill.opacity	numeric in [0,1]. Controls circle opacity if no opacity provided in fill or fill aesthetic.
marker	character. The 'pin' marker draws map pointers similar to most web map applications. The 'dot' or 'point' markers render as cicular points on the map. Other marker types are not supported by this method.
size	numeric point icon size scalar or vector scalars. Used only if no size aesthetic is provided in mapping. A value of 1 translates to an icon width of 40 pixels for "pin" markers, or 20 pixels for "dot" markers.
label	character vector of point feature labels.
label.params, tooltip.params	named lists (e.g., list(property=value)) of label and tooltip position and format parameters. See ol_geom_polygon documentation.
tooltip	character vector of point feature tooltip popups.

Details

This function stores the data required to generate an OpenLayers vector layer with features using Point geometries. See OpenLayers Point Documentation for details.

Value

A list object of class Layer.SpatialPoint.

Aesthetics

• fill

• size

See Also

ol_aes, ol_map, ol_geom_polygon, ol_geom_circle, ol_geom_line, ol_geom_icon

Examples

point.matrix <- matrix(
    c(
        -80.885+runif(10),
        25.282618+runif(10)
    ),
    ncol=2
)
point.df <- data.frame(
    pt.type=sample(c("A","B"),10,replace=TRUE),
    pt.value=runif(10)*10
)
miami.map <- ol_map(
    center=c(-80.385790,25.782618),
    zoom=9
) +
    streetmap()
miami.points <- ol_geom_point(
    point.matrix,
    df=point.df,
    mapping=ol_aes(fill=pt.type,size=pt.value),
    name="Random Points of Interest",
    marker="pin",
    toggle.control=TRUE,
    tooltip=point.df$pt.type
)
size.scale <- ol_scale_size_continuous(
    display=TRUE,
    draw.fill='green'
)
fill.scale <- ol_scale_fill_discrete(
    c(B='red',A='green'),
    display=TRUE
)
miami.points.map <- miami.map +
    miami.points +
    size.scale +
    fill.scale

## Not run: 
# Output to file and view
ol_map2HTML(
  miami.points.map,
  'Miami_points.html'
)
browseURL('Miami_points.html')

## End(Not run)

cemarks/ROpenLayers documentation built on March 31, 2022, 12:05 p.m.