Multi-type collision detection method and system of BIM lightweight model

The invention provides a multi-type collision detection method and system for a BIM lightweight model, relates to the field of multi-type collision detection, and aims to quickly and accurately discover hard collision and soft collision between models, find out unreasonable or wrong positions between drawings in advance, and adjust conflicts in a design model in time. The first-layer index structure can quickly calculate a potential collision professional model combination; the second-layer index structure determines a professional model to which the geometry belongs, continuously eliminates the geometry at a relatively far position by applying a mathematical method, and reduces the calculation amount of model intersection; and meanwhile, a space triangular patch pair intersection judgment algorithm is adopted, so that the calculation rate is improved, and the automatic and efficient detection capability of hard collision and soft collision of a large-volume model is improved. The method is used for multi-typ