Structures in GeoDict are 3D voxel images where each voxel has one of 256 possible material IDs. To each of these material IDs, a material can be assigned. This means that a structure in GeoDict can contain up to 256 different materials. Materials in GeoDict can contain all material properties that are needed for simulations in GeoDict.

The GeoDict Material Database is the place to store material data. A selection of standard materials is already predefined, but the true strength of the database is that it allows the user to define additional materials to be used in GeoDict simulations.

The information for each material in the GeoDict material database is saved as a *.txt file in the material database folder. Therefore, materials can either be edited in the material database editor or by editing the corresponding *.txt file. Materials can be exchanged by copying these *.txt files.

Materials can be assigned to GeoDict structures during the creation with GeoDict structure generation modules (e.g., FiberGeo, GrainGeo, WeaveGeo…) or during the import from e.g., µCT-scans. Additionally, they can be set for the structure currently in memory. When saving a structure in a GeoDict format (as *.gdt or *.gad file), its constituent materials and their properties are saved in that file, too.

This allows for directly simulating on a structure loaded from its file, there is no necessity to select the materials and their properties for the simulation run. However, it is always possible to change the materials and their properties prior to simulation.