Applications should be aware of this possibility and if possible, drop to the next zoom level to render that part of the map. Attributes are tables that only contain non-spatial data. This data is commonly joined with spatial data as required by an application. In addition to tiles, features, and attributes, GeoPackage has a well-defined extension mechanism to support use cases that are not part of the core standard.
Existing requirement clause extension examples include additional geometry types, additional SQL geometry functions, and additional tile image formats. New requirement clause extension examples include spatial indexes, triggers, additional tables, other BLOB column encodings, and other SQL functions. Files that use one or more extensions are by definition Extended GeoPackages. There are two categories of extensions, registered and community.
The extensions table describes the extensions that are in use in a GeoPackage. The columns for this table are:. Registered extensions have been reviewed and adopted by OGC and are for all intents and purposes part of the standard.
Most registered extensions are published as part of the core standard but they may be published independently as well. OGC acknowledges that there are use cases not covered by the GeoPackage standard. Implementers are welcome to use the extension mechanism defined here to develop community extensions. The extension mechanism provides advantages including discoverability the extensions in use can be discovered by scanning a single table and uniformity declaring that an extension is in use indicates that a defined set of requirements are being met.
However, this is a decision that should be made carefully as custom extensions do introduce interoperability risks. OGC manages a registry of community extensions.
OGC is unable to endorse community extensions. Therefore an Extended GeoPackage containing community extensions will not pass conformance tests. However, a community of interest MAY waive that requirement in its own GeoPackage profile, with the caveat that it must bear the responsibility of endorsing the new extension s. Implementers that are interested in developing their own extensions are encouraged to contact OGC to ensure that the extensions are developed in accordance with OGC policies and in a way that minimizes risks to interoperability.
OGC will consider adopting externally developed extensions that address a clear use case, have a sound technical approach, and have a commitment to implementation by multiple implementers. We recommend choosing the GeoPackage implementation that is best suited for your operational environment. Creating a GeoPackage Similarly, if you wish to create a new GeoPackage from scratch or from an existing source file such as a ShapeFile or. Therefore 1. Q How do I model multiple geometries in the same feature?
A See the modeling guidelines page. Q What is meant by a "native" GeoPackage library? A A native GeoPackage library is a library that is native to the device's operating system. Note that individual vendors may create their own native GeoPackage libraries to support different use cases. The GeoPackage standard is agnostic to libraries and APIs, focusing instead on the contents of the GeoPackages that act as inputs or outputs.
The primary use case for designing GeoPackage was mobile device use, and that's why SQLite was chosen as a platform. In this case OGC as an organization is specifying a technology. This is unusual for OGC and the decision was not made lightly, but practicality and ease of implementation won out over standards purity.
And we are happy to say we have yet to get any negative feedback on this decision -- probably because SQLite is considered more like a library than a standalone application. An Open Format for Geospatial Information GeoPackage is an open, standards-based, platform-independent, portable, self-describing, compact format for transferring geospatial information.
Highlighted News. OGC has adopted GeoPackage 1. Official Standards Information. OGC GeoPackage 1. Official Test Suite. OGC has developed an executable test suite for portions of the GeoPackage standard. For information on installing and running the test suite locally, see the GitHub page. Find Data Find Software Extensions. Guidance Participate FAQ. Q Can GeoPackage be extended? It supports GeoPackage Features as of version 1. The plugin is still a 'community module', so it is unsupported and only available as a nightly build in the community section.
ArcGIS ArcGIS Pro version 1. Compusult Compusult uses GeoPackage extensively across its geospatial management tools. As an integral part of its core functionality, GO Mobile provides read and write access to tiles and features. Compusult extends the functionality of GeoPackage by implementing several extensions that support styling, simplification, revisioning, elevation and relational metadata. Compusult's GO Mobile, using GeoPackage, is currently deployed in the field with multiple customers covering several different industries.
LuciadLightspeed also supports GeoPackage, as well as Lucy, the application template that comes with it.
Lucy Test Drive and another application template GeoPackage Viewer for Android are both freely available for download.
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