CSGRegion
CSGRegion[{reg1,reg2,…}] represents the solid region corresponding to the union of solid regions reg1,reg2,….
CSGRegion["op",{reg1,reg2,…}] represents the solid region corresponding to the Boolean combination "op" of regions reg1,reg2,….
CSGRegion["op",{…,wi[regi],…}] represents the solid region defined by regions regi transformed by a geometric transformation wi.
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