ArcGIS Online includes a variety of basemaps that provide immediate geographic context for your operational layers. The basemaps are stored as tile layers, designed for fast and simple access by web maps, web apps, ArcGIS, and nearly any mapping software application. For example, you might include a basemap with tiles of streets in your neighborhood to provide a visual reference for the street signs in your feature layer. Tile layers are also useful when you need to expose a map or layer on the web for the visualization of relatively static data.
Tile layers come in different formats based on the original source data. Tile layers can be stored as prerendered raster tiles or as vector tiles. Both raster and vector tiles are designed to provide high-performance and high-scalability delivery of map data for visualization purposes.
Raster tile layers
Raster tile layers deliver basemaps to your client application as image files (for example, JPG or PNG format) that have been prerendered and stored on the server and are displayed as is by the client. Raster tile layers are most appropriate for basemaps that give your maps geographic context such as imagery (as in the World Imagery basemap) or feature-based maps such as in the Topographic, National Geographic, Oceans, and other basemaps. Raster tile layers can also be composed of static operational layers such as thematic maps of your data.
The tile layer format is fast to transmit over the Internet and is easily understood by most common mapping software applications, so these basemaps are compatible not only with ArcGIS and web apps built with the ArcGIS APIs, but also third-party apps that use OGC protocols such as WMS/WMTS. Other benefits of raster tile layers include the following:
- Work well across a wide range of applications and devices (web, desktop, and mobile), including desktop applications, such as ArcMap, and older versions of web browsers.
- Provide high-end cartographic capabilities such as advanced label placement and symbology.
- Support various raster data sources such as imagery and elevation data.
- Can be printed from web mapping applications.
Vector tile layers
Vector tile layers deliver map data as vector files (for example, PBF format) and include one or more layers that are rendered on the client based on a style delivered with the layer. Vector tiles include similar data to that found in some (but not all) of the available raster tile basemaps, but they store a vector representation of the data; that is, geographic features are represented as points, lines, and polygons in a format understood by the client application. Unlike raster tile layers, vector tile layers can adapt to the resolution of their display device and be restyled for multiple uses. Vector tiles have a smaller file size than raster tiles, which translates to faster maps and better performance. The combination of tile access performance and vector drawing allows the tiles to adapt to any resolution of the display, which may vary across devices.
In Map Viewer, client-side drawing of vector tiles allows you to customize the style of the vector tile layer and the contents of the map. Other advantages of vector tile layers include the following:
- Can be used to generate many different map styles using a single set of vector tiles. You can customize vector tile layers—for example, hide their visibility, change symbols and fonts, change languages for labels, and so on—without having to regenerate tiles.
- Look great on high-resolution displays (for example, retina devices) that offer much better resolution than low-resolution (96 dpi) raster tiles, without the need for generating separate, high-resolution versions. Vector tiles can be displayed at any scale level with clear symbology and labels in desktop applications such as ArcGIS Pro.
- Can be generated much more quickly, and with fewer hardware resources, than corresponding raster tiles. This reduces the cost to generate the tiles and improves the speed at which data updates can be made available.
- Vector tiles are much smaller in size than corresponding raster tiles, reducing the cost to store and serve the tiles.
- Can be projected into various coordinate systems, using desktop applications such as ArcGIS Pro, without distortion of labels and other symbols.
Vector tile layers have the best performance on machines with newer hardware, and they can be displayed in most current versions of desktop browsers, including Chrome, Firefox, Safari, Internet Explorer 11, and Edge. You can add vector tile layers as operational layers or basemaps to Map Viewer or Scene Viewer.
Vector basemaps are available in Map Viewer and Scene Viewer, as well as in ArcGIS Pro, configurable apps that include a basemap gallery, Workforce for ArcGIS, Explorer for ArcGIS, and apps created using Web AppBuilder. To find out whether vector basemaps are available in a specific ArcGIS app, refer to the app documentation.
Vector basemaps include a number of styles that you can customize. Visit the Esri vector basemap group to see sample vector styles you can use as well as what can be done to change the look of the map. Sample styles include simple color changes and more involved redesigns using sprite and font changes. The vector basemaps are updated frequently and include regular contributions from the GIS community.
With ArcGIS Pro 1.2 and later, you can share a vector tile package to your organization and publish the uploaded vector tile package as a hosted layer. With ArcGIS Pro 1.4 and later, you can publish a hosted vector tile layer from a map in ArcGIS Pro directly to ArcGIS Online.