R传单情节船方向

Question

我有关于船只/船只的位置以及它们正在驾驶的航线的信息。我想将它们绘制在带有自定义图标的传单地图上，该图标看起来像一艘船。我发现glyphicons 中的"tags" 图标最合适。以下是一些可供使用的数据：

dput(head(x))
structure(list(boatName = c("Conti Benguela", "Sunny Bay", "Sunny Horizon", 
"FMT URLA", "Qi Xiang 22", "STI Solidarity"), lat = c(37.115365, 
38.4772017, 14.632, 56.80515, 51.31172, -2.2783283), lon = c(15.2682183, 
-8.7888783, -79.5806667, 7.601885, -143.5678933, 46.6328383), 
    cog = c("16", "331", "182", "21", "288", "72")), row.names = c(NA, 
6L), class = "data.frame")

cog 表示地面上的路线，图标转换为旋转角度。我正在使用以下代码来绘制当前船舶的位置和根据船舶转向的方向的旋转：

shipIcon <- makeAwesomeIcon("tag",iconRotate = x$cog)
leaflet() %>% addTiles() %>% 
  addAwesomeMarkers(lng=x$lon,lat=x$lat,icon=shipIcon,popup = x$boatName)

但是，如您所见，makeAwesomeIcon 为我不想要的图标添加了背景标记。我看过this 和this，后者正是我想要做的。如何在没有标记背景的情况下根据它正在转向的路线显示带有旋转的自定义船图标的任务？

Answer 1

概述

为了绘制图标方向，我遵循了三个步骤：

1. 为了在传单地图上呈现 HTML 图标，我将 leaflet::makeAwesomeIcon() 替换为 leaflet::makeIcon()。

2. 为了启用图标旋转，我存储了a leaflet.rotatedMarker.js file 和registered this plugin as a leaflet object 的本地副本。

1234563 >

注意：第 2 步和第 3 步取自 SO 问题 icon rotation in leaflet package 的答案和评论。所有功劳归于@rrs 和@Ufos。

在做任何事情之前，我运行了您的代码并得到了以下传单地图：

使用boat.icon，图标被旋转但更难阅读：

最终，我决定使用亮橙色leaflet::addCircleMarkers() 和指北针图标来显示位置和旋转角度：

代码

# load necessary packages
library( htmltools )
library( htmlwidgets )
library( leaflet )

# this is taken from: https://gist.github.com/jcheng5/c084a59717f18e947a17955007dc5f92
# "Leaflet.rotatedMarker" is taken from https://raw.githubusercontent.com/bbecquet/Leaflet.RotatedMarker/master/leaflet.rotatedMarker.js
rotatedMarker <- 
  htmlDependency( name = "Leaflet.rotatedMarker" # note: this .js file has to be copied and stored in your current working directory 
                  , version = "0.1.2"
                  , src = normalizePath( path = getwd() )
                  , script = "leaflet.rotatedMarker.js" )

# this is taken from: https://gist.github.com/jcheng5/c084a59717f18e947a17955007dc5f92
registerPlugin <- function(map, plugin) {
  map$dependencies <- c(map$dependencies, list(plugin))
  map
}

# store data
df <-
  structure(list(boatName = c("Conti Benguela", "Sunny Bay", "Sunny Horizon", 
                              "FMT URLA", "Qi Xiang 22", "STI Solidarity"), lat = c(37.115365, 
                                                                                    38.4772017, 14.632, 56.80515, 51.31172, -2.2783283), lon = c(15.2682183, 
                                                                                                                                                 -8.7888783, -79.5806667, 7.601885, -143.5678933, 46.6328383), 
                 cog = c("16", "331", "182", "21", "288", "72")), row.names = c(NA, 
                                                                                6L), class = "data.frame")

# store boat png
boat.file <- "http://cdn.onlinewebfonts.com/svg/download_498189.png"

# store north arrow png
north.arrow.file <- "https://upload.wikimedia.org/wikipedia/commons/a/aa/Aiga_uparrow.svg"

# make boat icon
boat.icon <- 
  makeIcon( iconUrl = boat.file
            , iconWidth = 25
            , iconHeight = 25 )

# make north arrow icon
north.arrow.icon <-
  makeIcon( iconUrl = north.arrow.file
            , iconWidth = 10
            , iconHeight = 10 )

# display leaflet map
leaflet( data = df ) %>%
  addProviderTiles( provider = "OpenStreetMap.BlackAndWhite" ) %>%
  registerPlugin( plugin = rotatedMarker ) %>%
  addCircleMarkers( lng = ~lon
                    , lat = ~lat
                    , radius = 5
                    , fillColor = "orange"
                    , fillOpacity = 1
                    , stroke = FALSE ) %>%
  addMarkers( lng = ~lon
              , lat = ~lat
              , label = ~boatName
              , icon = north.arrow.icon
              , options = markerOptions( rotationAngle = ~cog ) )

# end of script #

会话信息

R version 3.4.4 (2018-03-15)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS High Sierra 10.13.2

Matrix products: default
BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods  
[7] base     

other attached packages:
[1] leaflet_1.1.0.9000 htmlwidgets_1.0    htmltools_0.3.6   

loaded via a namespace (and not attached):
 [1] shiny_1.0.5     compiler_3.4.4  magrittr_1.5   
 [4] R6_2.2.2        markdown_0.8    tools_3.4.4    
 [7] yaml_2.1.18     Rcpp_0.12.16    crosstalk_1.0.0
[10] jsonlite_1.5    digest_0.6.15   xtable_1.8-2   
[13] httpuv_1.3.6.2  mime_0.5