R: GetMap bbox

GetMap.bbox {RgoogleMaps} | R Documentation

## GetMap bbox

### Description

Wrapper function for GetMap. Query the Google server for a static map tile, defined primarily by its lat/lon range and/or center and/or zoom. Multiple additional arguments allow the user to customize the map tile.

### Usage

    GetMap.bbox(lonR, latR, center, size = c(640, 640), destfile = "MyTile.png",
        MINIMUMSIZE = FALSE, RETURNIMAGE = TRUE, GRAYSCALE = FALSE,
        NEWMAP = TRUE, zoom, verbose = 0, SCALE = 1, ...)

### Arguments

`lonR` | longitude range
`latR` | latitude range
`center` | optional center
`size` | desired size of the map tile image. defaults to maximum size returned by the Gogle server, which is 640x640 pixels
`destfile` | File to load the map image from or save to, depending on `NEWMAP`.
`MINIMUMSIZE` | reduce the size of the map to its minimum size that still fits the lat/lon ranges ?
`RETURNIMAGE` | return image yes/no default: TRUE
`GRAYSCALE` | Boolean toggle; if TRUE the colored map tile is rendered into a black & white image, see RGB2GRAY
`NEWMAP` | if TRUE, query the Google server and save to `destfile`, if FALSE load from destfile.
`zoom` | Google maps zoom level. optional
`verbose` | level of verbosity
`SCALE` | use the API's scale parameter to return higher-resolution map images. The scale value is multiplied with the size to determine the actual output size of the image in pixels, without changing the coverage area of the map
`...` | extra arguments to GetMap

### Value

map tile

### Author(s)

Markus Loecher

### Examples

     mymarkers <- cbind.data.frame(lat = c(38.898648,38.889112, 38.880940),
              lon = c(-77.037692, -77.050273, -77.03660), size =  c('tiny','tiny','tiny'),
              col = c('blue', 'green', 'red'), char = c('','',''));

    ##get the bounding box:
      bb <- qbbox(lat = mymarkers[,"lat"], lon = mymarkers[,"lon"]);

    ##download the map:
      MyMap <- GetMap.bbox(bb$lonR, bb$latR, destfile = "DC.png", GRAYSCALE =TRUE,
                    markers = mymarkers);
     ##The function qbbox() basically computes a bounding box for the given lat,lon
       #points with a few additional options such as quantile boxes, additional buffers, etc.
      bb <- qbbox(c(40.702147,40.711614,40.718217),c(-74.015794,-74.012318,-73.998284),
                TYPE = "all", margin = list(m=rep(5,4), TYPE = c("perc", "abs")[1]));
     ##download the map:
    MyMap <- GetMap.bbox(bb$lonR, bb$latR,destfile = "MyTile3.png", maptype = "satellite")

[Package RgoogleMaps version 1.4.1 Index]