In the terminology of the software these pieces are called Components.
In VCarve Pro this is achieved by letting the user work with pieces of the design which are combined to make the finished part. In any situation, the best approach to producing something complicated is to break it down into smaller pieces until a level of simplicity is reached that can be understood and managed. VCarve Pro has been designed to work in a way which enables the user to easily create even very complex projects. If working in a 2 Sided environment you can view both sides of a project in the 3D View using the Multi Sided View option. The visibility of these calculated toolpaths can be controlled from the Toolpath List on the Toolpaths tab using the check-boxes next to the toolpaths name. In addition to these items, you can see line drawings of any calculated toolpaths in the 3D View. If your part contains any visible 3D Components then as soon as the Preview Toolpaths form is closed it will revert to showing the Composite Model in the 3D View and hide the simulation. When this is closed if you are working on a part that only includes 2D data and 2D or 2.5D toolpaths it will continue to display the Preview Material Block. Whenever you have the Preview Toolpaths form open on the Toolpaths tab, the 3D View displays the Preview Material Block instead of the Composite Model. Which of these is currently displayed will depend on whether or not you have a part which has 3D Components and Toolpaths or are just working on something that only includes 2D Data. The 3D View can show you the current Composite Model (which is built from all of the currently visible 3D Components and Levels), the Toolpath Preview (a highly accurate 3D simulation of the resulting physical object that will result from your toolpaths called the Preview Material Block). These toolpaths are created from 3D design elements called 3D Components that can be generated from models created in external 3D design packages As well as creating toolpaths directly from 2D drawings, VCarve Pro can produce extremely flexible 3D toolpaths.