Glossary of all terms used

This page explains terminology used throughout the SDK.

A Coordinate represents an exact geographical location in a specific CRS.

A CRS is the EPSG Code of a Coordinate Reference System that used to interpret Coordinates, see Coordinate Reference Systems.

To share Spatial Information with Viewer a CRS code is required. The Default CRS, used by Viewer SDK returns is EPSG:4326 WGS84. This Viewer SDK CRS can be set only at initialization of the Viewer.

A Field-Of-View is the representation of the position, direction or bounds of a View on the Reference Map.
Field-Of-Views are provided by the SDK as MapObjects.

A Footprint is the representation of a visible Resource on the Reference Map. Footprints are useful to indicate data availability. Footprint can be Photo Position, Simplified Coverage or Envelope.
Footprints are provided by the SDK as MapObjects. The SDK returns what it determines as most appropriate for the given Map Scale.

MapObjects are the representation of current Views and visible Resources on the Reference Map. MapObjects have a Spatial Component and include Styling parameters.
The SDK returns MapObject instances whenever something should be rendered on the Reference Map.
The Developer should implement rendering of MapObjects once. This reduces integration effort and makes the plugin future proof.

A MapObject has a core type property that categorizes the MapObject into a group. Each group should be rendered into its owner Layer :

• fov : Object represents a View field-of-view.
• footprint : Object represents a Resource Footprint.

A MapObject has a property that determines its spatial type :

• spatialLine
• spatialArea
• spatialPoint

To use the Viewer a Login is required :

• 3DM Cloud Named User Login : Requires User and Password.
• 3DM Cloud Guest User Login : Requires a Publication or Bookmark token.
• 3MD Publisher Login : Requires Publisher Url, User, Password and Publication.

It is possible to Preset the login credentials or to use them to login automatically.
Preset requires the user to confirm and allows to pick another login option. Auto Login requires no user interaction and disables the option to use another login option.

Note: For security reasons we don't allow you to preset a 3DM Cloud Named User Login.

A Promise is a placeholder for a value that is yet to be defined. When the value is defined, a Promise is said to be 'pending'. When a value is eventually defined, the Promise resolves to that value. If a problem occurs the promise fails.

The user of a Promise can attach listeners to the Promise to be notified when the Promise either resolves or fails.

function handlePhotoPositionsResult(list) {
  console.log(list.toArray());
}
 
/* Find photo's. */
var promise = viewer.findPhotoPositions(orbitgt.mapping3d.sdk.viewer.Bounds.fromXY(0,0,1,1));
promise.then(this.handlePhotoPositionsResult,null/*optional-failure-handler*/);

A Signal can be best described as an event emitter. It manages a list of interested parties, and informs them if an event occurs. Its name usually reflects the event that is dispatched, for example : `onReady`.

Some signals have a `payload` when they dispatch.

By convention, signal names are camel-cased and always start with “on”.

viewer.onViewerOpened.add(this.handleViewerOpened);
 
function viewerOpened(viewerId) {
  console.log("Viewer "+viewerId+" just opened.");
  viewer.onViewerOpened.remove(this.handleViewerOpened);
}

The options below can be provided to the constructor when creating a new SDKViewer instance.

Guest Users, Named Users

A View is a single interactive component of the Viewer Workspace that visualizes the visible Resources, in some way or form.

A Workspace consists of a list of resources in a specific order. A workspace can also define a set of views and their layout. A workspace can also define resource legend parameters and other workspace settings (such as showing pointcloud data on top of photo views).