Boolean union operation method of three-dimensional planar entity

Abstract

The invention relates to a Boolean union operation method of a three-dimensional planar entity. The method is characterized in that for each plane in an entity A, the plane is stored when the plane isbeyond an entity B completely; if the plane and the plane of the entity B are in a same-direction and coplane manner and are not inner loop surfaces, two-dimensional Boolean union operation is carried out on the two planes and the operation result is stored; if the plane is not in the above-mentioned condition, the plane cuts off the entity B to obtain a profile polygon, two-dimensional Boolean subtraction operation is carried out on the plane and the profile polygon and the operation result is stored; the entity A and the entity B are switched and the same treatment is carried out on the entities respectively; and post treatment including repeated plane deletion, suspension plane deletion, and plane merging is carried out on the stored results to obtain a Boolean union operation result of the entity A and the entity B. The method has advantages of being simple, being easy to implement, having rigorous algorithm logic, having perfect geometric completeness, and having low arithmetic operation load and can be applied to three-dimensional entity modeling in fields of CAD, CAM, CAE, computer animation, virtual reality and 3D printing.

Description

technical field [0001] The invention belongs to the technical field of computer graphics, and relates to a Boolean union operation method for three-dimensional plane entities, specifically a method for obtaining a new three-dimensional entity through the Boolean union operation of two three-dimensional plane entities. Background technique [0002] Boolean union operation is one of the core algorithms of Boolean operations on 3D planar entities, which can be used for 3D entity modeling in CAD, CAM, CAE, computer animation, virtual reality, 3D printing and other fields. [0003] With the continuous development of computer graphics, especially the rapid development of 3D visualization, virtual reality technology, 3D printing technology, etc., 3D modeling technology with independent intellectual property rights has become an urgent need in many fields, and 3D entities based on Boolean operations Modeling techniques are a top priority. Boolean operations on 3D solids include uni...

AI Technical Summary

Problems solved by technology

[0004]Three-dimensional entity Boolean operation is very mature in commercial software, but its implementation method is rarely seen in open literature

The patent has the following problems: First, it does not consider the fact that the surfaces of two planar entities are in the same direction and in the same plane, which will lead to errors when the two entities are merged, resulting in the inability to perform joint modeling that is often used in engineering; second, the algorithm is redundant. For other calculations, such as A_in_B and B_in_A are not used in the union operation, A_out_B and B_out_A are not used in the intersection operation, A_in_B and B_out_A are not used in the difference operation A-B, and A_out_B and B_in_A are not used in the difference operation B-A

It can be seen that the existing research results have the following problems: (1) The completeness of the algorithm lacks strong theoretical support; (2) The algorithm is complex and difficult to implement; (3) The algorithm is not efficient and has a large amount of calculation

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