The 3D solids can be defined either by using the component toolbar or by importing them from other 3rd party software (CATIA, Pro/Engineer...) with the standard STEP or IGES format. The Open Cascade library included in FASTRAD provides advanced visualization capabilities like cut operations, complex shape management, and STEP and IGES exchange format modules. The advanced STEP module allows you to import the hierarchy, name and color information. The full 3D designer model is then managed by FASTRAD (visualization, radiation calculation, post-processing).