Union, difference and intersection 并+差+交

• The set that contains all points of set A and all points of set B, but nothing else, is called the union of A and B.
• The intersection of A and B is defined as the set of all points that belong both to A and to B.
• The difference of A and B contains only those points of A that do not lie in B. Analogously, the difference of B and A consists of points of B that are not contained in A.

Trim and split 修剪+裂开

• Boolean operations do not work when surfaces are involved
• When it comes to modeling with surfaces, we use the techniques of trimming and splitting.