R/createInitialization.R

In plotGoogleMaps: Plot Spatial or Spatio-Temporal Data Over Google Maps

createInitialization <-
  function(SP,
           name="map",
           zoom=15,
           mapTypeId = "HYBRID",
           fitBounds=TRUE,
           add=FALSE,
           divname="map_canvas",
           disableDefaultUI=FALSE,
           disableDoubleClickZoom =FALSE,
           draggable= TRUE ,
           keyboardShortcuts=TRUE,
           mapTypeControlOptions='DEFAULT',
           navigationControl=TRUE,
           navigationControlOptions='DEFAULT',
           noClear=FALSE,
           scaleControl=TRUE,
           scaleControlOptions= 'STANDARD',
           scrollwheel =TRUE,
           streetViewControl= FALSE) {
    
    if(scaleControl != FALSE) {
      scaleControl <- 'true'
    } else {
      scaleControl <- 'false' 
    }
    
    if(disableDefaultUI != FALSE) {
      disableDefaultUI <- 'true'
    } else {
      disableDefaultUI <- 'false' 
    }
    
    if(disableDoubleClickZoom != FALSE) {
      disableDoubleClickZoom='true'
    } else { 
      disableDoubleClickZoom='false' 
    }
    
    if(draggable != FALSE) { 
      draggable <- 'true'
    } else { 
      draggable <- 'false' 
    }
    
    if(keyboardShortcuts != FALSE) {
      keyboardShortcuts <- 'true'
    } else { 
      keyboardShortcuts <- 'false' 
    }
    
    if(navigationControl != FALSE) { 
      navigationControl <- 'true'
    } else {
      navigationControl <- 'false' 
    }
    
    if(noClear != FALSE) {
      noClear <- 'true'
    } else {
      noClear <- 'false' 
    }
    
    if(scaleControl != FALSE) { 
      scaleControl <- 'true'
    } else {
      scaleControl <- 'false'
      scaleControlOptions <- 'null'
    }
    
    if(scrollwheel != FALSE) {
      scrollwheel <- 'true'
    } else { 
      scrollwheel <- 'false' 
    }
    
    if(streetViewControl != FALSE) {
      streetViewControl <- 'true'
    } else { 
      streetViewControl <- 'false' 
    }
    
    mapTypeId <- paste('google.maps.MapTypeId.',mapTypeId,sep="")
    mapTypeControlOptions <- paste('{style: google.maps.MapTypeControlStyle.',
                                   mapTypeControlOptions,'}',sep="")
    navigationControlOptions <- paste('{style: google.maps.NavigationControlStyle.',
                                      navigationControlOptions ,'}',sep="")
    if(!is.null(scaleControlOptions)){
      scaleControlOptions <- paste('{style: google.maps.ScaleControlStyle.',
                                   scaleControlOptions ,'}',sep="")  }
    
    SP.ll <- spTransform(SP, CRS("+proj=longlat +datum=WGS84"))
    ## If SP was already in the required projection, use the original SP to preserve @bbox settings
    ## spTranform() will reset @bbox to show entire object
    if(identicalCRS(SP,SP.ll)) {
      SP.ll <- SP
    }
    
    Centar <- c(mean(SP.ll@bbox[1,]),mean(SP.ll@bbox[2,]))
    sw <- c(SP.ll@bbox[2,1],SP.ll@bbox[1,1])
    ne <- c(SP.ll@bbox[2,2],SP.ll@bbox[1,2])
    
    x <- 'function initialize() {\n'
    
    x <- paste(x,' var latlng = new google.maps.LatLng(',Centar[2],',',Centar[1],');\n',sep="")
    x <- paste(x,'\n var myOptions = { zoom:',zoom,',\n center: latlng',',\n mapTypeId:',mapTypeId,
               ',\n disableDefaultUI:',disableDefaultUI,',\n disableDoubleClickZoom:',disableDoubleClickZoom,
               ',\n draggable:',draggable,',\n keyboardShortcuts: ', keyboardShortcuts,
               ',\n mapTypeControlOptions:', mapTypeControlOptions, ',\n navigationControl:',navigationControl,
               ',\n navigationControlOptions:',navigationControlOptions,',\n noClear:',noClear,
               ',\n scaleControl:', scaleControl ,',\n scaleControlOptions:',scaleControlOptions,
               ',\n scrollwheel:', scrollwheel, ',\n streetViewControl:',streetViewControl,' };\n',sep="")
    
    x <- paste(x,'\n',name)
    x <- paste(x,' = new google.maps.Map(document.getElementById("',divname,'"),myOptions);\n\n',sep="")
    
    if(fitBounds == TRUE) {
      x <- paste(x,' ',name,'.fitBounds(new google.maps.LatLngBounds(\n
  new google.maps.LatLng(',sw[1],',',sw[2],'),\n
  new google.maps.LatLng(',ne[1],',',ne[2],')));\n',sep="")  
    }
    
    ## If this is the last map layer, close the JavaScript function
    if(!add) { 
      x <- paste0(x,'}\n')
    }
    
    return(x)
  }