! scope="col"| Ray Interaction Type
! scope="col"| Object Types Allowed
! scope="col"| Notes
|-
| style="width:30px;" | [[File:impenet_group_icon.png]]
| style="width:250px;" | Ray reflection, ray diffraction
| style="width:250px;" | All solid & surface geometric objects, no curve objects
| style="width:250px;" | Basic building group for outdoor scenes
|-
| style="width:30px;" | [[File:penet_surf_group_icon.png]]
| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Penetrable Surface | Penetrable Surface]]
| style="width:250px;" | Ray reflection, ray diffraction, ray transmission through thin walls
| style="width:250px;" | All solid & surface geometric objects, no curve objects
| style="width:250px;" | Uses thin wall approximation for transmitted rays
|-
| style="width:30px;" | [[File:terrain_group_icon.png]]
| style="width:250px;" | Ray reflection, ray diffraction
| style="width:250px;" | All surface geometric objects, no solid or curve objects
| style="width:250px;" | Behaves exactly like impenetrable surface but can change the elevation of all the buildings and transmitters and receivers located above it
|-
| style="width:30px;" | [[File:penet_vol_group_icon.png]]
| style="width:250px;" | Ray reflection, ray diffraction, ray transmission in material media
| style="width:250px;" | All solid geometric objects, no surface or curve objects
| style="width:250px;" | Models a volumetric material block
|-
| style="width:30px;" | [[File:base_group_icon.png]]
| style="width:250px;" | Either ray generation or ray reception
| style="width:250px;" | Only point objects
| style="width:250px;" | Required for the definition of transmitters and receivers
|}