Tile layers are useful when you need to expose a map or layer on the web for the visualization of relatively static data.
The basemaps included in an ArcGIS Enterprise portal are tile layers that provide immediate geographic context for your operational layers. For example, you can include a basemap with tiles of streets in your map to provide a visual reference for the street signs in a feature layer that is also in the map. The basemaps included in ArcGIS Enterprise are designed for fast and simple access by web maps, web apps, ArcGIS, and nearly any mapping software application.
Tile layers come in various 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 layer
A raster tile layer is composed of cached raster tiles, also called map tile caches. These are delivered to client applications as image files (for example, JPG or PNG format) that have been prerendered and stored in ArcGIS Enterprise. The tiles are statically displayed 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 cached tiles are fast to transmit over the internet and are easily understood by most common mapping software applications, so they are compatible not only with ArcGIS and web apps built with the ArcGIS APIs, but also third-party apps that use Open Geospatial Consortium (OGC) protocols such as WMTS. Raster tile layers can do the following:
- Work well across a wide range of applications and devices (web, desktop, and mobile), including desktop applications and older versions of web browsers.
- Provide high-end cartographic capabilities such as advanced label placement and symbology.
- Support compressed three-band imagery and elevation data.
- You can print them from web mapping applications.
WMTS layers
Hosted WMTS layers are OGC-compliant views of hosted tile layers. All hosted tile layers that are shared with the public can be accessed using the OGC WMTS protocol. The publisher of the hosted tile layer does not have to perform any special operations to enable WMTS. To access a hosted tile layer using the WMTS protocol, open the layer's item page and open the URL for the tile layer. The page that opens contains a WMTS URL link to the WMTS capabilities document that can be used to access layer tiles in apps that support WMTS.
Raster tile layer creation
The following sections describe the methods you can use to create a raster tile layer in an ArcGIS Enterprise portal.
From a service definition file
A service definition file (.sd) is an archive of the source data or references to the source data that is needed to generate the cache.
Use a service definition file to publish a hosted tile layer when you want ArcGIS Enterprise to generate the layer's cache. The source data is copied to the portal, so you can generate cached tiles for the desired scale levels on the portal whenever needed.
The cached tiles are generated using the resources on the ArcGIS Enterprise portal's hosting server, and the caches are stored in the hosting server's cache directory.
注意:
It is recommended that you do not build tiles during the portal's peak usage hours.
Once you publish the hosted tile layer, edits to the source data cannot be used to update the tile layer.
The following functionality is available when you publish a hosted tile layer from a service definition file:
- Build tiles—You can adjust the visible range and build tile caches for the extents you specify.
- Visible range—You can modify the extent and scales at which the tile layer will draw.
- Update content—You can replace the content of the tile layer with content from another layer.
See Publish hosted tile layers for instructions to publish from a service definition file.
From a tile package
A tile package is an archive of cached tiles generated locally.
Use a tile package to publish a hosted tile layer to avoid using the resources of the ArcGIS Enterprise machines for cache generation. When you publish, the tile caches are uploaded to the hosting server's cache directory.
注意:
This workflow can be time consuming for large packages because the tile content is uploaded to ArcGIS Enterprise. Ensure that the ArcGIS Enterprise portal content directory and the ArcGIS cache directory on the hosting server have twice as much free disk space available as the size of the tile package.
The cache already exists, so there is no need to build tiles after you publish from a tile package.
The following functionality is available when you publish a hosted tile layer from a tile package:
- Visible range—You can modify the extent and scales at which the tile layer will draw.
- Update content—You can replace the content of the tile layer with content from another layer.
See Publish hosted tile layers for instructions to publish from a tile package.
From a hosted feature layer
If you have a hosted feature layer that is frequently accessed by users for viewing purposes only, you can publish a hosted tile layer from the hosted feature layer. Having cached tiles improves rendering times as compared to accessing the same data in the hosted feature layer.
It is recommended that you publish a hosted vector tile layer in this case; however, if you cannot publish a vector tile layer, you can publish a hosted tile layer from the feature layer instead.
When you publish a hosted tile layer from a hosted feature layer, the resources of the hosting server are used for cache generation, storage, and rendering.
The following functionality is available when you publish a hosted tile layer from a hosted feature layer or hosted feature layer view:
- Build tiles—You can adjust the visible range and build tile caches for the extents you specify.
- Visible range—You can modify the extent and scales at which the tile layer will draw.
- Update content—After features are edited in the associated hosted feature layer, rebuild the tiles in the tile layer to incorporate changes from the feature layer.
See Publish a hosted tile layer for instructions.
Reference precreated caches in a user-maintained data store
You can create a cache dataset, place it in a folder or cloud data store that is registered with a federated ArcGIS Server site, and create a tile layer that references the cache dataset.
Use the Extract Package geoprocessing tool in ArcGIS Pro to create the cache dataset or write your own tool using the Esri tile package open specification.
The layer is published to the server you specify when publishing. The layer references the cache dataset in the cloud or folder data store.
Use this method for publishing a tile layer if you want to control the storage location for the tile caches or when working with large tile content. This workflow is significantly faster, as no content needs to be uploaded to the portal, and disk space allocation is not needed in the server cache directories. The throughput of the tile layer is determined by the bandwidth of the connection to the data store.
The cache dataset already exists, so there is no need to build tiles after you publish the tile layer.
The following functionality is available when you publish a tile layer that references a cache dataset in a folder or cloud data store:
- Visible range—You can modify the extent and scales at which the tile layer will draw.
- Update content—You can replace the content of the tile layer with content from another layer.
See Publish a tile layer from a cache dataset for instructions.
Vector tile layers
A vector tile layer references a set of web-accessible vector tiles and the corresponding style for how those tiles should be drawn. Vector tiles are similar to raster tile layers, 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 static 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.
For more information on vector tile layers, view the following ArcGIS StoryMaps content:
In Map Viewer Classic (formerly known as Map Viewer), you can customize the style of the vector tile layer and the contents of the map. Other properties of vector tile layers include the following:
- You can use a single set of vector tiles to generate many map styles. For example, you can change symbols and fonts or change languages for labels on a vector tile layer without having to regenerate tiles.
- Vector tile layers display at high resolution (for example, on retina devices). Vector tiles can be displayed at any scale level with clear symbology and labels in desktop applications such as ArcGIS Pro.
- Vector tiles are much smaller in size than corresponding raster tiles. Therefore, they take less time to build and require less disk space to store.
- Desktop applications, such as ArcGIS Pro, can project vector tile layers into various coordinate systems without distortion of labels and other symbols.
- When you publish a vector tile layer from ArcGIS Pro (2.8 and later), you can simultaneously publish an associated feature layer. Editors can update the data in the feature layer and you can rebuild the vector tile cache to incorporate the edits into the vector tile layer.
You can add vector tile layers as operational layers or basemaps to Map Viewer (formerly a separate beta installation but now present in the portal automatically), Map Viewer Classic, Scene Viewer, ArcGIS Pro, ArcGIS Collector, ArcGIS Workforce, and ArcGIS Explorer. You can also use maps and scenes with vector tile layers in web apps, using ArcGIS Configurable Apps, ArcGIS Web AppBuilder, ArcGIS Maps SDK for JavaScript, and ArcGIS Runtime SDKs.
Esri provides basemaps delivered as vector tiles. They 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 how 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 your organization.
Considerations for using vector tile layers
The following are some considerations for using vector tile layers:
- Vector tile layers can be displayed in most current versions of desktop browsers, including Google Chrome, Mozilla Firefox, and Safari.
- Vector tile layers have the best performance on machines with newer hardware because they require display drivers that support WebGL.
Vector tile layer creation
The following sections describe the methods you can use to create a vector tile layer in an ArcGIS Enterprise portal.
From a vector tile package
A vector tile package is an archive of cached vector tiles generated locally from ArcGIS Pro.
Use a vector tile package to publish a hosted vector tile layer to avoid using the resources of the ArcGIS Enterprise machines for cache generation. When you publish, the vector tile caches are uploaded to the hosting server's cache directory.
注意:
This workflow can be time consuming for large packages because the vector tile content is uploaded to ArcGIS Enterprise. Ensure that the ArcGIS Enterprise portal content directory and the ArcGIS cache directory on the hosting server have twice as much free disk space available as the size of the vector tile package.
The cache already exists, so there is no need to build tiles after you publish from a vector tile package.
You can replace the content of the vector tile layer with content from another layer.
See Publish hosted vector tile layers for instructions to publish from a vector tile package.
Reference precreated caches in a user-maintained data store
You can create a cache dataset, place it in a folder or cloud data store that is registered with a federated ArcGIS Server site, and create a tile layer that references the cache dataset.
Use the Extract Package geoprocessing tool in ArcGIS Pro to create the cache dataset or write your own tool using the Esri tile package open specification.
The layer is published to the server you specify when publishing. The layer references the cache dataset in the folder or cloud data store.
Use this method for publishing a vector tile layer if you want to control the storage location for the caches or when working with large vector tile content. This workflow is significantly faster, as no content needs to be uploaded to the portal, and disk space allocation is not needed in the server cache directories. The throughput of the vector tile layer is determined by the bandwidth of the connection to the cloud or folder data store.
The cache dataset already exists, so there is no need to build tiles after you publish the vector tile layer.
You can replace the content of the vector tile layer with content from another layer.
See Publish a vector tile layer from a cache dataset for instructions.
When to create each type of tile layer
Both raster tile layers and vector tile layers support a wide range of symbology sets and display features faster than feature or dynamic map layers because they only need to access the tile caches rather than source data. If you need this functionality, publish a tile layer. But when should you use a raster tile layer and when should you use a vector tile layer?
The main purpose of raster tile layers is to provide an image basemap to give important context for the vector layers in the map. For example, roads present in imagery have variable width and shoulders that allow ingress and egress of emergency vehicles, allow storage of material and equipment, and provide other decision support information. Additionally, orthoimage basemaps, accessed as raster tile layers, are often used to revise outdated vector landbase layers. Raster tiles can also serve elevation data that is used to provide terrain for 3D scenes.
Vector tile layers can be scaled and projected into various coordinate systems without distortion of labels and other symbols. They use less disk space and take less time to build caches than raster tile layers.
When you publish a vector tile layer from ArcGIS Pro, you can publish an associated feature layer with it. If you need to update the vector data included in the vector tile layer on a frequent basis (hourly, daily, weekly), publish an associated feature layer with the vector tile layer. When you do this, you and the other editors with whom you share the feature layer can edit data in the feature layer. You can then periodically rebuild the vector tile layer cache to incorporate the edits made in the feature layer.
What you consider a frequent update depends on how often you can rebuild the vector tile layer cache and how long you consider it acceptable for there to be differences between the feature layer and vector tile layer data. For example, if the feature layer data is edited daily and you rebuild the vector tile layer cache each evening, there is a one day lag before edits made to the feature layer show up in the vector tile layer. This is likely acceptable. But if you can only rebuild the vector tile layer cache once a week and the feature layer is being edited hourly, the layers will be out of sync for a week. If that is not acceptable and you are unable to increase the frequency with which you rebuild the vector tile cache, consider publishing a feature layer only, publish a read-only hosted feature layer view from it, and have clients access it instead. You lose the rich symbology and display performance advantages, but you ensure all clients see feature updates immediately.
When you include a feature layer when you publish the vector tile layer, you have the additional choice of keeping the feature data in your data source (reference the registered data) or copying the data to the relational data store. If your source is an enterprise geodatabase or database and other clients or processes will update the data directly in the database, publish a feature layer that references the registered data source. If all feature edits will take place through a hosted feature service, publish a feature layer that copies the data.
If the data doesn't get updated often or at all, you can publish the vector tile layer only. If you do need to update the content of this type of vector tile layer, you can replace it with another vector tile layer.