Maps

AIS-Server is using the web-application to display vessel position and other attributes on a map. The standard Web Map Service protocol is used to request background maps from a selected map server, and to generate the transparent overlay map with vessel information.

Map Options

Options regarding the map appearance can be set:

  • Include/exclude base stations in the map.
  • Select refresh rate.
  • Choose between a set of predefined background maps,.
  • Style for presenting the vessels .

Map Features

Pushbuttons give access to a set of map features:

  • The user interface has all the navigational functionality you will expect from a map system, such as "zoom in", "zoom out", "zoom to region", "pan" and set "next", "previous" or "home" region.

  • Pressing the "info" button and clicking on a vessel gives all information available for a vessel.

  • One can "track" a specific vessel. The system will then "follow" this vessel and change the map region when required.

  • It is also possible to make a snapshot of a map. The map image is then generated with a higher quality and annotated with the time the snapshot is representing, before it is sent to the user and shown in a separate browser window.

  • The "tool tip" function shows some of the attributes for a vessel as a "tool tip".

  • The "calendar" button gives access to historical data within a certain period.

  • The "time step" buttons give possibilities to go backward and forward in time.

Map Presentation

The presentation of vessels on the map is adjusted to the scale of the map. With more detailed maps, more details of the vessel will be visible.

The "smart" placement of the labels is optimised for minimal occlusion of other labels.

If there are too many labels in an area, no labels will be shown at all for that area. Zooming further in will then reveal the labels for the vessels.

When the full details for a vessel are visible, you can see:

  • Size of vessel coded as a triangle with colour coded speed (moving/not moving) or status (active/inactive)
  • Heading and rate of turn vectors
  • Course over ground and speed over ground vector (10 minutes)
  • Vessel track (10 minutes)
  • Ship dimension
  • Ship name/call sign with speed or time not moving, as a label
Click for larger image
Click on picture for larger image

Performance

Many web map servers are built using a traditional "single-user" map engine as a basis. This often results in bad performance when several users access the map server simultaneously. The AIS Server is utilizing a map engine designed from the ground up by CMR, with multi user web map access in mind. This means that the AIS Server map engine performs well also when many users are connected.