A single-sided internal geometric feature cleaning method, system, medium, and apparatus
Patent Information
- Application Number
- CN202610813355.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-06-08
- Publication Date
- 2026-09-25
AI Technical Summary
1）全局遍历整个模型的所有曲面及其内环，逐个识别出需要清理的目标特征并完成删除，在仅清理某一曲面上的特征时，也不得不遍历整个模型，例如飞机、汽车这类包含成千上万个曲面的大型模型，全局遍历会增加清理时间；
[0015]与现有技术相比，本发明的一种单面内几何特征清理方法的有益效果如下：通过用户选择的目标特征，直接确定该特征所在的待清理曲面并调用其曲面信息，将全部操作限定于单一曲面内部，避免了全局遍历整个模型的所有曲面及内环，从而缩短清理时间；还通过构建包括裁剪信息的拓扑关联表，并依据曲面信息及裁剪信息依次进行特征清理及参数域恢复，无需采用反向布尔运算，从而避免了布尔运算对非目标曲面及共享拓扑关系的破坏。
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Figure CN122818445A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of feature cleaning technology, and in particular to a method, system, medium, and device for cleaning geometric features within a single surface. Background Technology
[0002] In the fields of computer-aided design (CAD) and computer-aided engineering (CAE), complex geometric models often incorporate internal geometric features such as holes, slots, and recesses. These features have corresponding structural functions or functional value in the initial design stage. However, when the model enters simulation analysis, digital manufacturing, or subsequent stages that require model simplification, these internal features often need to be removed to ensure computational efficiency and mesh quality, or to make the model practically feasible for manufacturing.
[0003] Current mainstream internal feature cleanup methods have the following problems when they only need to clean up features within a certain surface: 1) Globally traverse all surfaces and their inner loops of the entire model, identify the target features that need to be cleaned one by one and complete the deletion. When only cleaning features on a certain surface, it is also necessary to traverse the entire model. For example, for large models such as airplanes and cars that contain tens of thousands of surfaces, global traversal will increase the cleaning time. 2) By using reverse Boolean operations, the regions of the model that originally had features are filled into complete surfaces. However, Boolean operations can easily affect surfaces that do not need to have their features cleared and the shared topological relationships between surfaces, which can lead to problems such as model damage, loss of patches, and broken adjacency relationships. Therefore, when using the mainstream feature cleaning methods in the existing technology to clean the features of a single surface of a model, problems such as long cleaning time and damage to the original topological structure of the model may occur. Summary of the Invention
[0004] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method, system, medium and device for cleaning up geometric features in a single face, which does not require global traversal of the entire model or the use of reverse Boolean operations, so as to avoid the problems of long cleaning time and damage to the original topology of the model.
[0005] A method for cleaning up geometric features within a single surface is provided, including: In response to the target feature selected by the user, the surface to be cleaned where the target feature is located is determined, and the surface information of the surface to be cleaned is retrieved; Based on the surface information, a topological association table of the target feature is constructed, the topological association table including clipping information for cleaning up the target feature; Based on the surface information and the trimming information, the surface to be cleaned is sequentially cleaned up and the parameter domain is restored to obtain the initial surface; Based on the topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface; The reconstructed surface is subjected to integrity verification. If the verification passes, the reconstructed surface is determined as the target surface after the target feature has been cleaned.
[0006] Optionally, the surface information includes the surface type and inner loop structure; calling the surface information of the surface to be cleaned includes: The surface type is obtained by calling the underlying geometry type attribute of the surface to be cleaned; The loop list of the surface to be cleaned is called, and the inner loop structure is obtained based on the loop list.
[0007] Optionally, based on the surface information, a topological association table of the target feature is constructed, including: Based on the target feature, determine the target inner ring structure of the target feature in the inner ring structure; Based on the target's inner ring structure, construct a topological association table for the target features.
[0008] Optionally, based on the surface information and the trimming information, feature cleaning and parameter domain recovery are sequentially performed on the surface to be cleaned to obtain an initial surface, including: Based on the trimming information, feature cleaning is performed on the surface to be cleaned to obtain a cleaned surface; The initial surface is obtained by restoring the parameter domain of the cleaned surface based on the surface information.
[0009] Optionally, feature cleaning is performed on the surface to be cleaned based on the trimming information to obtain a cleaned surface, including: Based on the clipping information, the feature face to be cleaned, the feature edge to be cleaned, and the adjacency topology pointer are determined. The feature face to be cleaned is composed of the feature face to be cleaned, and the adjacency topology pointer is used to indicate the shared edge pointer between the feature face to be cleaned and the adjacent face. Delete the feature face and the feature edge to be cleaned, and unbind the shared edge between the surface to be cleaned and the adjacent face according to the adjacency topology pointer to obtain the cleaned surface.
[0010] Optionally, the surface information includes the original parameter domain of the surface to be cleaned where the target feature is absent; the parameter domain is recovered from the cleaned surface based on the surface information to obtain the initial surface, including: Obtain the parameter domain of the cleaned surface; Based on the original parameter domain, the parameter domain of the cleaned surface is restored so that the parameter domain of the cleaned surface is the same as the original parameter domain, thus obtaining the initial surface.
[0011] Optionally, based on the topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface, including: Based on the topological association table, extract the original shared edges between the initial surface and adjacent surfaces, and the invalid topological pointers pointing to the feature edges to be cleaned; The bidirectional topological pointers between the initial surface and the original shared edge, and between the adjacent surface and the original shared edge, are reconstructed. The original shared edge is used as the outer loop of the initial surface, and the invalid topological pointers are cleaned up to obtain the reconstructed surface.
[0012] A single-face in-plane geometric feature cleaning system is also provided, which applies the above-mentioned single-face in-plane geometric feature cleaning method, including: The surface information retrieval module, in response to the target feature selected by the user, determines the surface to be cleaned where the target feature is located, and retrieves the surface information of the surface to be cleaned; The feature cleanup module is used for: Based on the surface information, a topological association table of the target feature is constructed, the topological association table including clipping information for cleaning up the target feature; Based on the surface information and the trimming information, the surface to be cleaned is sequentially cleaned up and the parameter domain is restored to obtain the initial surface; Based on the topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface; The surface verification module is used to perform integrity verification on the reconstructed surface. If the verification passes, the reconstructed surface is determined as the target surface after the target feature has been cleaned.
[0013] A computer-readable storage medium is also provided, which is a computer-readable storage medium storing a computer program thereon, wherein the computer program, when executed, implements the aforementioned method for cleaning up geometric features within a single face.
[0014] A computer device is also provided, including a processor and a memory, wherein the memory stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement the single-sided in-plane geometric feature cleaning method.
[0015] Compared with the prior art, the beneficial effects of the single-surface geometric feature cleaning method of the present invention are as follows: by selecting the target feature by the user, the surface to be cleaned is directly determined and its surface information is called, limiting all operations to the interior of a single surface, avoiding global traversal of all surfaces and inner loops of the entire model, thereby shortening the cleaning time; furthermore, by constructing a topological association table including clipping information, and performing feature cleaning and parameter domain restoration sequentially according to the surface information and clipping information, there is no need to use reverse Boolean operation, thereby avoiding the destruction of non-target surfaces and shared topological relationships by Boolean operation. Attached Figure Description
[0016] Figure 1 This is a flowchart of the cleaning method of the present invention. Detailed Implementation
[0017] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0018] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of this application.
[0019] In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims. In the description of this application, it should be understood that the terms "first," "second," "third," etc., are used only to distinguish similar objects and are not necessarily used to describe a specific order or sequence, nor should they be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0020] See Figure 1 As shown, a method for cleaning up geometric features within a single surface according to the present invention includes: S1: In response to the target feature selected by the user, determine the surface to be cleaned where the target feature is located, and call the surface information of the surface to be cleaned; In one embodiment of the present invention, the surface information includes the surface type and inner ring structure; calling the surface information of the surface to be cleaned includes: calling the underlying geometry type attribute of the surface to be cleaned to obtain the surface type; calling the ring list of the surface to be cleaned, and obtaining the inner ring structure based on the ring list.
[0021] The underlying geometry type attribute of the surface is used to identify the mathematical definition of the surface. This underlying geometry type attribute is directly stored in the underlying data structure of the surface and can be obtained without geometric calculation or fitting. Therefore, after determining the surface to be cleaned, this invention can call the underlying geometry type attribute based on the unique identifier of the surface to be cleaned. The surface type includes, but is not limited to, non-uniform rational B-spline (NURBS) and B-spline surface (B-Spline). This invention can quickly obtain the surface type of the surface to be cleaned by calling this underlying geometry type attribute.
[0022] The ring list of this invention is a data set used to store boundary rings in the surface topology structure. Each surface includes an outer ring for indicating the outer boundary of the surface and an inner ring for indicating the closed boundaries of features such as holes, grooves, and depressions inside the surface. The ring list distinguishes the outer boundary of the surface from the closed boundaries of the internal features. By directly calling the ring list, the inner ring results of the surface to be cleaned can be obtained without reconstructing the topology of the surface to be cleaned. The inner ring structure includes, but is not limited to, the number of inner rings on the surface to be cleaned, the set of boundary curves of each inner ring, and the UV interval of the closed boundary of each inner ring in the parameter domain.
[0023] This invention can quickly obtain the surface type and inner loop structure required for feature cleaning by directly calling the surface information of the surface to be cleaned, without traversing the entire model or rebuilding the topology. Furthermore, by directly calling the surface information, no changes such as writing, modifying, or deleting the model are required, thus ensuring that the model is not damaged during the data acquisition phase.
[0024] S2: Based on the surface information, construct a topological association table of the target features. The topological association table includes clipping information for cleaning the target features. This invention uses clipping information to locate the target features on the surface to be cleaned, so as to accurately clean the target features and avoid cleaning errors that could damage the surface to be cleaned.
[0025] In one embodiment of the present invention, constructing a topological association table of target features based on surface information includes: determining the target inner ring structure of the target features in the inner ring structure based on the target features; and constructing a topological association table of the target features based on the target inner ring structure.
[0026] The inner ring structure obtained in step S1 of this invention includes inner ring information of multiple features on the surface to be cleaned. By determining the target inner ring structure of the target feature, a localized topological association record is achieved only for the target feature based on the topological association table of the target inner ring structure components. This avoids traversing all inner ring features on the surface to be cleaned, effectively shortening the time for constructing the topological association table. Moreover, the topological association table is only related to the complexity of the target feature itself. When constructing the topological association table, its time complexity is O(m·e_avg), where m is the number of inner rings of the target feature and e_avg is the average number of edges of a single inner ring. The time complexity of constructing the topological association table is independent of the total size of the model where the surface to be cleaned is located, significantly reducing the computational cost of constructing the topological association table.
[0027] S3: Based on the surface information and trimming information, perform feature cleaning and parameter domain restoration on the surface to be cleaned in sequence to obtain the initial surface, including: performing feature cleaning on the surface to be cleaned based on the trimming information to obtain the cleaned surface; and performing parameter domain restoration on the cleaned surface based on the surface information to obtain the initial surface.
[0028] In one embodiment of the present invention, feature cleaning is performed on the surface to be cleaned according to the trimming information to obtain a cleaned surface, including: determining the feature surface to be cleaned, the feature edge to be cleaned, and the adjacency topology pointer according to the trimming information, wherein the feature surface to be cleaned is composed of the feature variable to be cleaned, and the adjacency topology pointer is used to indicate the shared edge pointer between the feature surface to be cleaned and the adjacent surface; deleting the feature surface to be cleaned and the feature edge to be cleaned, and unbinding the shared edge between the feature surface to be cleaned and the adjacent surface according to the adjacency topology pointer to obtain a cleaned surface.
[0029] This invention completely removes target features by deleting both the feature surfaces and edges to be cleaned. This avoids the problem in existing technologies where the feature region is filled into a complete surface using reverse Boolean operations, resulting in only the feature surfaces being cleaned while the feature edges remain, thus causing the residual feature edges to become ghost data. Furthermore, by unbinding the shared edges between the feature surface to be cleaned and its adjacent surfaces, the topological relationship between the feature surface to be cleaned and its adjacent surfaces is severed. This prevents the feature surface from being deleted along with its shared edges when it is deleted, which could lead to problems such as damaged geometry and incomplete topology of the adjacent surfaces.
[0030] In one embodiment of the present invention, the surface information includes the original parameter domain of the surface to be cleaned without target features; the parameter domain recovery of the cleaned surface according to the surface information to obtain an initial surface includes: obtaining the parameter domain of the cleaned surface; and recovering the parameter domain of the cleaned surface according to the original parameter domain so that the parameter domain of the cleaned surface is the same as the original parameter domain to obtain the initial surface.
[0031] This invention restores the parameter domain of a cleaned surface by retrieving the original parameter domain, making the parameter domain of the cleaned surface identical to the original parameter domain. This eliminates the voids in the parameter domain left after the target feature is deleted, restoring a continuous and unbroken parameter space. Furthermore, the parameter domain restoration process of this invention only deletes the clipping constraints of the target feature, without modifying the control points, order, and node vectors of the cleaned surface. Therefore, it achieves parameter domain repair while ensuring that the original geometry, curvature, and smoothness of the cleaned surface remain unchanged.
[0032] S4: Based on the topological association table, reconstruct the adjacency relationship of the initial surface to obtain the reconstructed surface, including: extracting the original shared edges between the initial surface and adjacent surfaces and the invalid topological pointers pointing to the feature edges to be cleaned according to the topological association table; reconstructing the bidirectional topological pointers between the initial surface and the original shared edges, and between the adjacent surfaces and the original shared edges, using the original shared edges as the outer loop of the initial surface, and cleaning up the invalid topological pointers to obtain the reconstructed surface.
[0033] This invention reconstructs the initial surface and adjacent surfaces through bidirectional topology pointers, enabling them to reconnect via the original shared edges. This achieves the correct restoration of the relationship between the closed boundary of the surface after target feature cleanup and the adjacent surfaces. Furthermore, by using the original shared edges as the outer ring of the initial surface, it ensures the complete closure of the external boundary of the initial surface, guaranteeing that the topological structure of the initial surface is undamaged and free of voids. Simultaneously, it cleans up invalid topology pointers, preventing issues such as access errors, program crashes, or data inconsistencies that could occur during subsequent operations such as meshing and simulation calculations on the cleaned target feature model due to residual dangling pointers pointing to deleted feature surfaces or edges.
[0034] S5: Perform an integrity check on the reconstructed surface. If the check passes, the reconstructed surface is identified as the target surface after the target features have been cleaned, including: The reconstructed surface undergoes local verification, including: verifying the existence of isolated edges or curves; verifying the validity of topological pointers, loop closures, and adjacency relationships; verifying the continuity and integrity of the parameter domain without voids; and verifying the closure and integrity of the outer loop structure. If the reconstructed surface has no isolated edges or curves, valid topological pointers, valid loop closures, valid adjacency relationships, a continuous and complete parameter domain without voids, and an unbroken outer loop structure, then the local verification passes. A global verification is performed on the reconstructed surface, including: verifying whether the topological connection between the reconstructed surface and its adjacent surfaces is stable and unbroken; obtaining the entity or shell to which the reconstructed surface belongs and verifying whether the entity or shell to which the reconstructed surface belongs maintains a closed, effective, and undamaged complete structure; if the topological connection between the reconstructed surface and its adjacent surfaces is stable and unbroken, and the entity or shell to which the reconstructed surface belongs maintains a closed, effective, and undamaged complete structure, then the global verification passes. If both local and global verifications pass, the integrity verification of the reconstructed surface passes, and the reconstructed surface is determined as the target surface. This invention uses local verification to determine that the local geometry and topology of the surface are completely valid, and uses global verification to ensure that the model after feature cleaning of a single surface meets the requirements of subsequent CAD / CAE processing and analysis.
[0035] The present invention provides a single-sided feature cleaning system, which applies a single-sided in-plane geometric feature cleaning method according to any one of claims 1-7, characterized in that it includes: The surface information retrieval module responds to the target feature selected by the user, determines the surface to be cleaned where the target feature is located, and retrieves the surface information of the surface to be cleaned. The feature cleanup module is used for: Based on the surface information, a topological association table of the target features is constructed. The topological association table includes clipping information for cleaning up the target features. Based on the surface information and trimming information, feature cleaning and parameter domain restoration are performed sequentially on the surface to be cleaned to obtain the initial surface; Based on the topological association table, the adjacency relationship of the initial surface is reconstructed to obtain the reconstructed surface; The surface verification module is used to verify the integrity of the reconstructed surface. If the verification passes, the reconstructed surface is identified as the target surface after the target features have been cleaned.
[0036] This invention discloses a computer-readable storage medium storing a computer program thereon, which, when executed, implements the single-sided in-plane geometric feature cleaning method.
[0037] Optionally, the computer-readable storage medium may include: read-only memory (ROM), random access memory (RAM), solid-state drives (SSDs), or optical discs, etc. The random access memory may include resistive random access memory (ReRAM) and dynamic random access memory (DRAM).
[0038] The computer device of the present invention includes a processor and a memory. The memory stores at least one instruction, at least one program, code set, or instruction set. The at least one instruction, at least one program, code set, or instruction set is loaded and executed by the processor to implement the above-described method for cleaning up geometric features within a single surface.
[0039] The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.
[0040] The memory can be used to store the computer program or module. The processor implements various functions of the single-sided geometric feature cleaning method by running or executing the computer program or module stored in the memory and calling the data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function, etc.; the data storage area may store data created based on the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital card (SD), flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.
[0041] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A method for cleaning up geometric features within a single surface, characterized in that, include: In response to the target feature selected by the user, the surface to be cleaned where the target feature is located is determined, and the surface information of the surface to be cleaned is retrieved; Based on the surface information, a topological association table of the target feature is constructed, the topological association table including clipping information for cleaning up the target feature; Based on the surface information and the trimming information, the surface to be cleaned is sequentially cleaned up and the parameter domain is restored to obtain the initial surface; Based on the topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface; The reconstructed surface is subjected to integrity verification. If the verification passes, the reconstructed surface is determined as the target surface after the target feature has been cleaned.
2. The method for cleaning up geometric features within a single surface according to claim 1, characterized in that, The surface information includes the surface type and inner loop structure; calling the surface information of the surface to be cleaned includes: The surface type is obtained by calling the underlying geometry type attribute of the surface to be cleaned; The loop list of the surface to be cleaned is called, and the inner loop structure is obtained based on the loop list.
3. The method for cleaning up geometric features within a single surface according to claim 2, characterized in that, Based on the surface information, a topological association table for the target feature is constructed, including: Based on the target feature, determine the target inner ring structure of the target feature in the inner ring structure; Based on the target's inner ring structure, construct a topological association table for the target features.
4. The method for cleaning up geometric features within a single surface according to claim 1, characterized in that, Based on the surface information and the trimming information, the surface to be cleaned is sequentially subjected to feature cleaning and parameter domain restoration to obtain an initial surface, including: Based on the trimming information, feature cleaning is performed on the surface to be cleaned to obtain a cleaned surface; The initial surface is obtained by restoring the parameter domain of the cleaned surface based on the surface information.
5. The method for cleaning up geometric features within a single surface according to claim 4, characterized in that, Based on the trimming information, feature cleaning is performed on the surface to be cleaned to obtain a cleaned surface, including: Based on the clipping information, the feature face to be cleaned, the feature edge to be cleaned, and the adjacency topology pointer are determined. The feature face to be cleaned is composed of the feature face to be cleaned, and the adjacency topology pointer is used to indicate the shared edge pointer between the feature face to be cleaned and the adjacent face. Delete the feature face and the feature edge to be cleaned, and unbind the shared edge between the surface to be cleaned and the adjacent face according to the adjacency topology pointer to obtain the cleaned surface.
6. The method for cleaning up geometric features within a single surface according to claim 4, characterized in that, The surface information includes the original parameter domain of the surface to be cleaned where the target feature is absent; the parameter domain is recovered from the cleaned surface based on the surface information to obtain the initial surface, including: Obtain the parameter domain of the cleaned surface; Based on the original parameter domain, the parameter domain of the cleaned surface is restored so that the parameter domain of the cleaned surface is the same as the original parameter domain, thus obtaining the initial surface.
7. The method for cleaning up geometric features within a single surface according to claim 6, characterized in that, Based on the aforementioned topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface, including: Based on the topological association table, extract the original shared edges between the initial surface and adjacent surfaces, and the invalid topological pointers pointing to the feature edges to be cleaned; The bidirectional topological pointers between the initial surface and the original shared edge, and between the adjacent surface and the original shared edge, are reconstructed. The original shared edge is used as the outer loop of the initial surface, and the invalid topological pointers are cleaned up to obtain the reconstructed surface.
8. A single-sided feature cleaning system, employing the single-sided internal geometric feature cleaning method according to any one of claims 1-7, characterized in that, include: The surface information retrieval module, in response to the target feature selected by the user, determines the surface to be cleaned where the target feature is located, and retrieves the surface information of the surface to be cleaned; The feature cleanup module is used for: Based on the surface information, a topological association table of the target feature is constructed, the topological association table including clipping information for cleaning up the target feature; Based on the surface information and the trimming information, the surface to be cleaned is sequentially cleaned up and the parameter domain is restored to obtain the initial surface; Based on the topological association table, the adjacency relationships of the initial surface are reconstructed to obtain the reconstructed surface; The surface verification module is used to perform integrity verification on the reconstructed surface. If the verification passes, the reconstructed surface is determined as the target surface after the target feature has been cleaned.
9. A computer-readable storage medium, characterized in that, It is a computer-readable storage medium on which a computer program is stored, which, when executed, implements a method for cleaning up geometric features in a single face as described in any one of claims 1-7.
10. A computer device, characterized in that, The computer device includes a processor and a memory, the memory storing at least one instruction, at least one program, code set, or instruction set, the at least one instruction, at least one program, code set, or instruction set being loaded and executed by the processor to implement a single-sided in-plane geometric feature cleaning method as described in any one of claims 1 to 7.