**The drawbacks of WFM technique have been overcome**

**Domain**

While no representation can describe all possible solids, a representation should be able to represent a useful set of geometric objects.

**Unambiguity**

When you see a representation of a solid, you will know what is being represented without any doubt. An unambiguous representation is usually referred to as a complete one.

**Uniqueness**

That is, there is only one way to represent a particular solid. If a representation is unique, then it is easy to determine if two solids are identical since one can just compare their representations.

**Accuracy**

A representation is said accurate if no approximation is required.

**Validness**

This means a representation should not create any invalid or impossible solids. More precisely, a representation will not represent an object that does not correspond to a solid.

**Closure**

Solids will be transformed and used with other operations such as union and intersection. "Closure" means that transforming a valid solid always yields a valid solid.

**Compactness and Efficiency**

A good representation should be compact enough for saving space and allow for efficient algorithms to determine desired physical characteristics.