Fast distributed face-to-face matching method based on double-space lookup tree

Abstract

The invention provides a rapid distributed surface-to-surface matching method based on a double-space lookup tree, and relates to the field of numerical simulation, and the method comprises the steps: carrying out the distributed storage of a surface patch set A, and carrying out the centralized storage of a surface patch set B; respectively establishing a space search tree TreeA and a space search tree TreeB for the patch set A and the patch set B; each process of the storage patch set A traverses each layer of envelope box of the process TreeA, each layer of envelope box of the process TreeA traverses each layer of envelope box of the TreeB, and whether the two envelope boxes intersect is calculated; if so, calculating whether the patches in the two intersecting envelope boxes are accurately intersected; if the two patches intersect accurately, forming a matching pair by the two matched patches, and recording metadata information of the matching pair; all processes collect metadata information for the matching pairs of each process. According to the method, the problems of large calculation amount and low calculation efficiency when two groups of patch sets are traversed one by one for face-to-face matching in the prior art can be solved.

Description

Technical Field

[0001] The invention relates to the field of numerical simulation, and in particular to a fast distributed face-to-face matching method based on a dual-space search tree. Background Art

[0002] In numerical simulation calculations, problems such as contact and collision in dynamics and multi-domain coupling all involve the matching of mesh surfaces on both sides of the contact, collision or coupling interface.

[0003] The face-to-face matching method adopted in the prior art is to traverse the two sets of face sets involved in the matching one by one, and calculate whether each face in one set of face sets matches each face in the other set of face sets. Its spatial complexity level is the product of the number of faces in one set of face sets and the number of faces in the other set of face sets. This method has a large amount of calculation and low efficiency. Moreover, the current face-to-face matching methods are mostly single-core serial calculations. When the grid scale is large, the serial calculation will cause the face-to-face matching calculation to affect the solution efficiency of the entire simulation calculation. Summary of the invention

[0004] In response to the above-mentioned problems, the present invention provides a fast distributed face-to-face matching method based on a dual-space search tree, which can solve the problem of large amount of calculation and low efficiency when the prior art uses the method of traversing the two sets of facets involved in the matching one by one to perform face-to-face matching; it can reduce the spatial complexity of face-to-face matching and perform parallel calculations on face matching to improve the computational efficiency of face-to-face matching.

[0005] To achieve the above object, the technical solution adopted by the present invention is: The present invention provides a fast distributed face-to-face matching method based on a dual-space search tree, comprising the following steps: S101: Distribute and store a set of face sets A in each process, and centrally store another set of face sets B in each process; if both face sets A and B are distributedly stored, collect face set B in all processes and convert it into centralized storage; if both face sets A and B are centralizedly stored, divide face set A into processes and convert it into distributed storage; S102: establishing spatial search trees for the face set A and the face set B respectively, naming the spatial search tree established for the face set A as TreeA, and naming the spatial search tree established for the face set B as TreeB; S103: Each process storing the face set A traverses each layer of the envelope box of the current process TreeA, and for each layer of the envelope box of the current process TreeA, traverses each layer of the envelope box of TreeB, and calculates whether the envelope box of TreeA intersects with the envelope box of TreeB; S104: If the envelope box of TreeA intersects with the envelope box of TreeB, calculate whether the face pieces in the intersecting envelope boxes of TreeA and TreeB intersect exactly; S105: If the faces in the intersection envelope of TreeA and TreeB intersect exactly, the two matched faces are combined into a matching pair, and metadata information of the matching pair is recorded, where the metadata information includes the face number and the process number to which it belongs; S106: Detect whether each layer of envelope box of each process TreeA has traversed each layer of envelope box of TreeB. If traversed, all processes collect metadata information of matching pairs of each process, and end the face-to-face matching.

[0006] In the fast distributed face-to-face matching method based on dual space search trees provided by the present invention, preferably, in step S102, the space search tree is an AABB tree.

[0007] In the fast distributed face-to-face matching method based on dual-space search tree provided by the present invention, preferably, in step S104, the metadata information also includes the distance between facets and the normal vector.

[0008] The fast distributed face-to-face matching method based on dual-space search tree provided by the present invention preferably comprises, in step S106, a method for collecting metadata information of matching pairs of each process: collecting through global communication; or first writing metadata information of matching pairs into a file and then reading file data for collection.

[0009] The above technical solution has the following advantages or beneficial effects: The fast distributed face-to-face matching method based on dual spatial search trees provided by the present invention comprises the following steps: in step S101, two groups of face sets are preprocessed, wherein face set A is distributedly stored, and face set B is centrally stored, and the process using distributed storage of face set A has only partial face set information, while the process using centralized storage of face set B has complete face set information, and several processes using distributed storage of face set A can simultaneously perform face-to-face matching with several processes using centralized storage of face set B, thereby realizing face-to-face matching between face set A and face set B in parallel; in step S102, spatial search trees TreeA and TreeB are respectively established for face set A and face set B, and the spatial search tree can be used to generate an envelope box structure for faces, and invalid face matching pairs can be quickly filtered out in a large-grained envelope box space, thereby improving face-to-face matching. Matching efficiency; in step S103, by making each process storing the face set A traverse each layer of the envelope box of the process TreeA at the same time, and for each layer of the envelope box of the process TreeA, traverse each layer of the envelope box of TreeB respectively, the process using the distributed storage of the face set A is made to access the process using the centralized storage of the face set B in parallel, and calculate and determine whether the envelope box of TreeA intersects with the envelope box of TreeB. The face-to-face matching efficiency between the face set A and the face set B can be improved through parallel calculation; further, if the maximum number of faces of the distributed face set A in a single process is defined as M, the space complexity of the face set A in a single process is O(M), and the number of all faces of the face set B is defined as N, then the space complexity of the face set B is O(N), and the space complexity of the face-to-face matching between the face set A and the face set B is O(M * N), since the spatial search tree generates an envelope box structure for the face, by judging whether the envelope box of TreeA intersects with the envelope box of TreeB, if not, the face matching pair is abandoned, and there is no need to further calculate whether the faces are precisely intersected. The above method can filter invalid face matching pairs, reduce the scale of face-to-face matching calculation, and reduce the space complexity of matching calculation from O(M * N) to O(logM * logN), thereby further improving the face-to-face matching efficiency between the face set A and the face set B; in step S104 to step S105, if the envelope box of TreeA intersects with the envelope box of TreeB, it can be further calculated whether the faces in the intersecting envelope box of TreeA and TreeB are precisely intersected. If the faces in the intersecting envelope box of TreeA and TreeB are precisely intersected, the two matched faces are formed into a matching pair, and the metadata information of the matching pair is recorded, where the metadata information only includes the face number and the process number to which it belongs;In step S106, it is detected whether each layer of the envelope box of each process TreeA has traversed each layer of the envelope box of TreeB. If it has been traversed, all processes collect metadata information of the matching pairs of each process. Since the metadata information only includes the face number and the process number to which it belongs, a small amount of metadata information reduces the amount of global communication data of the matching pair, significantly improving the efficiency of parallel search for face-to-face matching. ; BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention and its features, configurations and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts throughout the drawings. The drawings are not drawn to scale, but rather to illustrate the subject matter of the present invention.

[0011] Figure 1 It is a flowchart of the fast distributed face-to-face matching method based on dual-space search tree provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0012] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention. Embodiment 1:

[0013] like Figure 1 As shown, a fast distributed face-to-face matching method based on a dual-space search tree provided in Embodiment 1 of the present invention includes the following steps: S101: Distribute and store a set of face sets A in each process, and centrally store another set of face sets B in each process; if both face sets A and B are distributedly stored, collect face set B in all processes and convert it into centralized storage; if both face sets A and B are centralizedly stored, divide face set A into processes and convert it into distributed storage; S102: establishing spatial search trees for the face set A and the face set B respectively, naming the spatial search tree established for the face set A as TreeA, and naming the spatial search tree established for the face set B as TreeB; S103: Each process storing the face set A traverses each layer of the envelope box of the current process TreeA, and for each layer of the envelope box of the current process TreeA, traverses each layer of the envelope box of TreeB, and calculates whether the envelope box of TreeA intersects with the envelope box of TreeB; S104: If the envelope box of TreeA intersects with the envelope box of TreeB, calculate whether the face pieces in the intersecting envelope boxes of TreeA and TreeB intersect exactly; S105: If the faces in the intersection envelope of TreeA and TreeB intersect exactly, the two matched faces are combined into a matching pair, and metadata information of the matching pair is recorded, where the metadata information includes the face number and the process number to which it belongs; S106: Detect whether each layer of envelope box of each process TreeA has traversed each layer of envelope box of TreeB. If traversed, all processes collect metadata information of matching pairs of each process, and end the face-to-face matching.

[0014] Embodiment 1 of the present invention provides a fast distributed face-to-face matching method based on dual spatial search trees. In step S101, two groups of face sets are preprocessed, wherein face set A is distributedly stored and face set B is centrally stored. The process using distributed storage of face set A has only partial face set information, while the process using centralized storage of face set B has complete face set information. Several processes using distributed storage of face set A can simultaneously perform face-to-face matching with several processes using centralized storage of face set B, thereby achieving face-to-face matching between face set A and face set B in parallel. In step S102, spatial search trees TreeA and TreeB are established for face set A and face set B, respectively. The spatial search tree can be used to generate an envelope box structure for the faces, and invalid face matching pairs can be quickly filtered out in a large-grained envelope box space, thereby improving Face-to-face matching efficiency; in step S103, by making each process storing the face set A traverse each layer of the envelope box of the process TreeA at the same time, and for each layer of the envelope box of the process TreeA, traverse each layer of the envelope box of TreeB respectively, the process using the distributed storage of the face set A is made to access the process using the centralized storage of the face set B in parallel, and calculate and determine whether the envelope box of TreeA intersects with the envelope box of TreeB. The face-to-face matching efficiency between the face set A and the face set B can be improved through parallel calculation; further, if the maximum number of faces of the distributed face set A in a single process is defined as M, the space complexity of the face set A in a single process is O(M), and the number of all faces of the face set B is defined as N, then the space complexity of the face set B is O(N), and the space complexity of the face-to-face matching between the face set A and the face set B is O(M * N), since the spatial search tree generates an envelope box structure for the face, by judging whether the envelope box of TreeA intersects with the envelope box of TreeB, if not, the face matching pair is abandoned, and there is no need to further calculate whether the faces are precisely intersected. The above method can filter invalid face matching pairs, reduce the scale of face-to-face matching calculation, and reduce the space complexity of matching calculation from O(M * N) to O(logM * logN), thereby further improving the face-to-face matching efficiency between the face set A and the face set B; in step S104 to step S105, if the envelope box of TreeA intersects with the envelope box of TreeB, it can be further calculated whether the faces in the intersecting envelope box of TreeA and TreeB are precisely intersected. If the faces in the intersecting envelope box of TreeA and TreeB are precisely intersected, the two matched faces are formed into a matching pair, and the metadata information of the matching pair is recorded, where the metadata information only includes the face number and the process number to which it belongs;In step S106, it is detected whether each layer of the envelope box of each process TreeA has traversed each layer of the envelope box of TreeB. If it has been traversed, all processes collect metadata information of the matching pairs of each process. Since the metadata information only includes the face number and the process number to which it belongs, a small amount of metadata information reduces the amount of global communication data of the matching pair, significantly improving the efficiency of parallel search for face-to-face matching. ;

[0015] Embodiment 1 of the present invention provides a fast distributed face matching method based on dual spatial search trees. Preferably, in step S102, the spatial search tree is an AABB tree. The AABB tree can generate an envelope box for each face in a face set. By determining whether the envelope boxes intersect, a large number of irrelevant faces can be quickly eliminated. In addition, a spatial search tree such as a quadtree with a similar function to the AABB tree can be used.

[0016] The fast distributed face-to-face matching method based on dual-space search tree provided in Embodiment 1 of the present invention preferably includes, in step S104, metadata information also carrying required contents such as inter-face distance and normal vector, for realizing functions such as collision detection.

[0017] In the fast distributed face-to-face matching method based on dual-space search tree provided in Example 1 of the present invention, preferably, in step S106, the method for collecting metadata information of the matching pairs of each process is: collecting metadata information of the matching pairs recorded on different processes through global communication between processes; or when recording the metadata information of the matching pairs in step S105, first writing the metadata information of the matching pairs into a file, and after the face-to-face matching is completed, reading the file data to obtain the metadata information of the matching pairs.

[0018] In summary, the fast distributed face-to-face matching method based on dual-space search trees provided by the present invention can solve the problem of large amount of calculation and low efficiency when the prior art uses the method of traversing the two sets of facets involved in the matching one by one to perform face-to-face matching; it can reduce the spatial complexity of face-to-face matching and perform parallel calculations on face matching to improve the computational efficiency of face-to-face matching.

[0019] Those skilled in the art should understand that those skilled in the art can implement the above-mentioned variations by combining the prior art and the above-mentioned embodiments, which will not be described in detail here. Such variations do not affect the essential content of the present invention, and will not be described in detail here.

[0020] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A fast distributed face-to-face matching method based on a dual-space search tree, characterized in that: The following steps are involved: S101: Distribute and store a set of face sets A in each process, and centrally store another set of face sets B in each process; if both face sets A and B are distributedly stored, collect face set B in all processes and convert it into centralized storage; if both face sets A and B are centralizedly stored, divide face set A into processes and convert it into distributed storage; S102: establishing spatial search trees for the face set A and the face set B respectively, naming the spatial search tree established for the face set A as TreeA, and naming the spatial search tree established for the face set B as TreeB; S103: Each process storing the face set A traverses each layer of the envelope box of the current process TreeA, and for each layer of the envelope box of the current process TreeA, traverses each layer of the envelope box of TreeB, and calculates whether the envelope box of TreeA intersects with the envelope box of TreeB; S104: If the envelope box of TreeA intersects with the envelope box of TreeB, calculate whether the face pieces in the intersecting envelope boxes of TreeA and TreeB intersect exactly; S105: If the faces in the intersection envelope of TreeA and TreeB intersect exactly, the two matched faces are combined into a matching pair, and metadata information of the matching pair is recorded, where the metadata information includes the face number and the process number to which it belongs; S106: Detect whether each layer of envelope box of each process TreeA has traversed each layer of envelope box of TreeB. If traversed, all processes collect metadata information of matching pairs of each process, and end the face-to-face matching.

2. The fast distributed face-to-face matching method based on dual-space search tree according to claim 1, characterized in that: In step S102, the spatial search tree is an AABB tree.

3. The fast distributed face-to-face matching method based on dual-space search tree according to claim 1, characterized in that: In step S104, the metadata information also includes the distance between patches and the normal vector.

4. The fast distributed face-to-face matching method based on dual-space search tree according to claim 1, characterized in that: In step S106, the method for collecting metadata information of the matching pair of each process is: collecting through global communication; or by first writing the metadata information of the matching pair into a file and then reading the file data for collection.

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