RalucaNicola

Level of detail

• symbols (whether 3D models or 2D symbols)
• 3D object scene layers

For maps we would rather use:

• Multiscale maps (see Author a multiscaled maps)
• Multilevel maps (GIS Cartography book by Gretchen Peterson)

Some concepts behind creating multiscale maps would be:

RalucaNicola

• Styling git bash article
• Bash colors
• Directory colors

RalucaNicola

All these commands can be followed along using this repository:

When I need to checkout a branch

I might not know the exact name of the branch, but I do know it contains some word

• git branch --r | grep -i <pattern>

Maybe I don't have all the branches in sync with the remote repo, so I need to fetch them:

• git fetch origin

RalucaNicola

Message of the map: figure out what are the high density population areas in the US.

Why would I use 3D? it looks more appealing, the user is excited to explore the map in 3D

Additional problems in 3D:

• harder to navigate
  • solution: navigation widgets; much more intuitive using touch navigation!
• hard to compare heights
• solution: mapping the same variable on both color and height;

RalucaNicola

1. Get the index of the layer you want to modify. To do that, run this snippet in the console:

view.map.allLayers.forEach(function(layer, index) {
  console.log(layer.title, "->", index);
});

2. Set the halo color, transparency and size by running the changeHalo function in the console.

RalucaNicola

How do I search for data?

• Search by ${topic} geodata on Google

• Go to a page I already know with data links:

  • Natural Earth: http://www.naturalearthdata.com/downloads/
  • Esri Living Atlas: https://livingatlas.arcgis.com/en/ (mostly for data published as esri services)
  • This awesome list of public geodata: https://freegisdata.rtwilson.com/ (unfortunately hard to keep up to date)

• Search for open data portals of the location I am interested in (most big cities have an open data portal)

  • Recently found: Esri Open Data & A map of open data portals

• Other repos/lists with data:

RalucaNicola

const webscene = new WebScene({
    ground: {
      opacity: 0 // set transparent ground
    }
});

const view = new SceneView({
    container: "viewDiv",
    map: webscene,
    qualityProfile: "high",

RalucaNicola

const contourLayer = new FeatureLayer({
    url: "https://services2.arcgis.com/cFEFS0EWrhfDeVw9/arcgis/rest/services/ContourLinesZurichDemo/FeatureServer",
    elevationInfo: {
      mode: "absolute-height",
      featureExpressionInfo: {
        expression: "Pow($feature.elevation,1.2)"
      }
    },
    renderer: {
      type: "simple",

RalucaNicola

const renderer = {
  type: "simple",
  symbol: {
    type: "polygon-3d",
    symbolLayers: [{
      type: "extrude",
      material: {
        color: [86, 72, 31]
      },
      size: 100

RalucaNicola

const hillsLayer = new FeatureLayer({
  url: "https://services2.arcgis.com/cFEFS0EWrhfDeVw9/arcgis/rest/services/HillsZurichDemo/FeatureServer",
  elevationInfo: {
    mode: "absolute-height",
    featureExpressionInfo: {
      expression: "Pow(Geometry($feature).Z, 1.2)"
    }
  },
  renderer: {
    type: "simple",