This paper presents new techniques for performing logical operations on type-2 fuzzy sets. These techniques make significant use of geometric methods to give, for the first time, logic operators that can be implemented over continuous domains, thereby eliminating the need for discretisation. We give a full exposition of the geometric inference operations and consider computational speed and accuracy. We show this novel approach to be more accurate, although slightly slower than existing techniques. Key words: Type-2 fuzzy logic, computational geometry, join, meet, and, or, implication, surface clipping.