In EM.Terrano, the scene elements like buildings, terrain objects and base points are grouped together based on their type. All the objects listed under a particular impenetrable surface group in the navigation tree share the same material properties and color and texture. To define a new block group, follow these steps:
# * Right click on the name of the element type in the navigation tree and select '''Insert New Block...''' A dialog for setting up the block properties opens up with a default color, texture and predefined material type (except for the case of a base point). # * Specify a name for the block group and select a color or texture.# * The electromagnetic model that determines ray-block interactions is specified under '''Interface Type''' or '''Surface Type'''. In most applications, you will use a standard materials with known electrical properties, i.e. '''Permittivity''' (ε<sub>r</sub>) and '''Electric Conductivity''' (σ). EM.Terrano does not handle magnetic materials.# * Click the '''OK''' button of the dialog to accept the changes and close it.
Once a new block node has been created on the navigation tree, it becomes the "Active" group of the project workspace, which is always displayed in bold letters. Then you can start drawing new objects under that node. Any block group can be made active by right clicking on its name in the navigation tree and selecting the '''Activate''' item of the contextual menu.