Extruded Buildings

The main entry point for extruded buildings is the MapBuildingLayer class, which can be retrieved by calling getMapBuildingLayer() from a Map. MapBuildingLayer provides methods for working with building groups and individual buildings such as:

• getBuilding()
• createNewBuildingGroup()
• releaseBuildingGroup()
• getDefaultBuildingGroup()

These APIs provide a way for the developer to create groups of buildings (for example, to highlight them in a blue color), or to retrieve a default group containing all possible extruded buildings on-screen.

The MapBuildingGroup class represents a group of buildings. There are two types of groups:

• New building groups - created by calling createNewBuildingGroup(). No building is attached to this group when it is created. An application can have a maximum of six new building groups at a time.
• Default building groups - retrieved by calling getDefaultBuildingGroup(). The default building group is a generic group that represents all possible buildings in the entire world. There are two distinct types of default building groups — IMPORTANT_BUILDINGS, which are textured landmark buildings, and NORMAL_BUILDINGS, which include all other buildings.

Each MapBuildingGroup holds an EnumSet of building faces, a color, as well as a building height scaling factor. To control the appearance of extruded buildings, you can set these attributes and add buildings to the group. For example, to highlight a building's roof, create a new building group, set the group's roof color as Color.RED and then add a building to this group as in the following code:

// retrieve a reference of the map from the map fragment
map = mapFragment.getMap();

// Create a custom building group
buildingGroup = map.getMapBuildingLayer().createNewBuildingGroup();

// Set the buildingGroup's roof color to "red"
buildingGroup.setColor(Color.RED, EnumSet.of(MapBuildingGroup.BuildingFace.ROOF));

// Set the buildingGroup's height
buildingGroup.setVerticalScale(0.90f);

buildingGroup.addBuilding(myBuildingIdentifier);

Figure 2. Highlighting a Building

The following images show the values that can be used to highlight building faces:

The MapBuildingObject class represents a single building with the following attributes:

• name
• geocoordinate position
• building height in meters
• unique map building identifier

private MapGesture.OnGestureListener gestureListener =
  new MapGesture.OnGestureListener.OnGestureListenerAdapter() {
    public boolean onMapObjectsSelected(List<ViewObject> objects) {
      for (ViewObject vo : objects) {
        if (vo instanceof MapBuildingObject) {
          // Remove currently selected building
          buildingGroup.removeAllBuildings();

          // Add this building to the group.
          MapBuildingObject building = (MapBuildingObject) vo;
          buildingGroup.addBuilding(building.getIdentifier());
        }
      }
      return false;
    }
  };