Question

我正试图在R中创建加拿大的互动离线地图经过一些搜索后，RgoogleMaps和Leaflet似乎是最好的选择。我在这里遵循了代码：R Leaflet Offline Map Tiles Not Loading

这是我的代码：

setwd("C:/Users/user/Documents")
library(servr)
library(RgoogleMaps)

# Load the tiles in working_folder/mapTiles/OSM/
for (zoom in 2:13)
  GetMapTiles("Canada", zoom = zoom,
             nTiles = round(c(20,20)/(17-zoom)))


# Start serving working folder on port 8000 in demon mode
deamon_id <- servr::httd(port = 8000, daemon = TRUE)

# Plot with leaflet
library(leaflet)
m = leaflet() %>% 
  addTiles( urlTemplate = 
     "http:/localhost:8000/mapTiles/OMS/{z}_{x}_{y}.png")
m = m %>% leaflet::setView(-76, 45 , zoom = 5)
m = m %>% leaflet::addMarkers(-76, 45 )
m

# Stop serving
servr::daemon_stop(deamon_id)

Hovever，当我在地图上放大/缩小时，灰色瓷砖出现在他们之前的地方：

This zoomed in image shows a grey tile over toronto

但是，

This more zoomed-out image shows toronto

关于什么是错误的任何想法？谢谢！

Answer 1

nTiles = round(c(20,20)/(17-zoom)) 该声明将无法始终如一地工作。如果要获取加拿大地图，可以不用指定nTiles，而是可以这样指定边界：lonR = c(-142,-52),latR = c(41,84)

离线R地图与RggogleMap和Leaflet

1 个答案: