A model is generated by an algorithm described by name, using specific parameters and slat variant. It holds the actual design,
in its calculated properties, and the slats.
The Slat is the building block of a rendering. Each slat shares a name (which describes its
role in the model; the name is not unique), a layer which is a zero-based index in the stack
of slats, its origin point as well as a vector defining the slats direction and length.