Error-free boundary evaluation based on a lazy rational arithmetic: a detailed implementation

A new boundary evaluation method is presented. It is based on error-free Boolean operations on polyhedral solids. W e describe, in detail, an intersection algorithm that handles, in a straightforward way, all the possible geometric cases. We also describe a general data structure that allows an unified storage of solid boundaries. The intersection algorithm always runs to completion, producing consistent solids from consistent operands. Numerical errors are handled at an algorithm independent level: an original exact arithmetic that performs only the necessary precise computations. Results from our implementation of this CSG solver are discussed.