Methods, apparatus, media, and equipment for surface trimming based on parametric meshes

Abstract

This invention belongs to the field of surface trimming technology, and provides a surface trimming method, apparatus, medium, and device based on parametric meshes. The technical solution involves parametrically segmenting the target surface and the tool surface to obtain corresponding segmented surface groups; performing interference judgment between the segmented surface groups to exclude incoherent segmented surfaces; calculating the intersection lines between interfering segmented surfaces as the trimming boundaries of the target surface; and trimming the target surface according to the trimming boundaries to obtain the trimmed surface. By parametrically segmenting the target surface and excluding incoherent parts, redundant calculations on irrelevant regions are avoided, effectively shortening the calculation time for intersection lines between complex surfaces, thereby improving the execution efficiency of the trimming tool.

Description

Technical Field

[0001] This invention belongs to the field of surface trimming technology, and particularly relates to surface trimming methods, devices, media and equipment based on parametric meshes. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The surface trimming function is an indispensable module in CAD design, used to remove unwanted parts from surfaces. This function uses the spatial intersection line between the target surface and the tool surface as the trimming boundary for precise trimming. However, when dealing with complex models, the trimming operation takes a long time to complete. This is mainly because determining the trimming boundary requires checking each facet (parametric mesh) to determine the intersection relationship. A large number of facets directly increases computational complexity and time costs. In industrial design, especially in high-precision fields like stamping dies, complex models may consist of tens of thousands or even millions of facets. During data processing, storing information on all facets and intermediate calculation results results in significant memory consumption. Furthermore, intersection line calculation is the most time-consuming step in the entire trimming process, leading to inefficient computation and severely impacting design efficiency, causing design workflow blockages. Summary of the Invention

[0004] To address at least one of the technical problems mentioned above, this invention provides a method, apparatus, medium, and device for surface trimming based on parametric meshes. By simplifying the number of parametric meshes involved in the calculation, it reduces the computational burden caused by the complexity of the surface, effectively shortens the calculation time for intersection lines between complex surfaces, and improves the efficiency of surface trimming.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A first aspect of the present invention provides a surface trimming method based on a parametric mesh, comprising the following steps:

[0007] Parametrically segment the target surface and the tool surface to obtain the corresponding segmentation surface group;

[0008] Interference is assessed between the segmented surface groups to exclude irrelevant segmented surfaces;

[0009] Calculate the intersection line between the interfering split surfaces, which serves as the clipping boundary of the target surface;

[0010] The target surface is trimmed according to the trimming boundary to obtain the trimmed surface.

[0011] Furthermore, the parametric segmentation of the target surface and the tool surface yields a corresponding set of segmented surfaces, including:

[0012] Determine whether the surface to be segmented is a surface. If it is, calculate the number of surface meshes and determine whether the number of surface meshes is greater than the set number. If so, segment the surface according to the parameter range of the surface and the set segmentation range to obtain the segmented surface group.

[0013] Furthermore, when segmenting the surface according to its UV range, each parametric mesh consists of multiple continuous longitudinal lines. u Parameter lines and along the horizontal v Composed of parameter lines.

[0014] Furthermore, interference judgment is performed between the segmented surface groups, including:

[0015] Let the target surface be denoted as F1, the tool surface as F2, and the corresponding segmented surface groups as GF1 and GF2, where the traversal number of GF1 is... i The traversal number of GF2 is j Traverse the segmentation face groups GF1 and GF2, calculate the bounding boxes of GF1[i] and GF2[j], and use the separation axis theorem to determine whether the two bounding boxes interfere. Only when the projections on all axes overlap are the two bounding boxes determined to interfere with each other, and the segmentation faces that do not interfere are excluded.

[0016] Furthermore, the method of using the separating axis theorem to determine whether two bounding boxes interfere includes: determining whether the projection ranges of the two bounding boxes overlap on the X-axis, Y-axis, and Z-axis respectively; if the projection ranges of bounding box B1 and bounding box B2 overlap on the X-axis, Y-axis, and Z-axis, then the two bounding boxes are judged to interfere; if the projection ranges of at least one axis do not overlap, then the two bounding boxes are judged not to interfere.

[0017] Furthermore, the intersection line between the segmented surfaces of the calculated interference, serving as the clipping boundary of the target surface, includes:

[0018] Calculate the intersection lines between the interfering split surfaces to obtain a set of intersection lines. Check whether the intersection lines in the set coincide and remove the coincident intersection lines to ensure that the intersection lines are unique. Sort the intersection lines and connect them in order according to the position of the beginning and end points of the intersection lines. Save the processed set of intersection lines as the final trimming boundary.

[0019] A second aspect of the present invention provides a surface trimming apparatus based on a parametric mesh, comprising:

[0020] The surface segmentation module is used to parametrically segment the target surface and the tool surface to obtain the corresponding segmentation surface group;

[0021] The interference check module is used to determine the interference between the segmented surface groups and exclude incoherent segmented surfaces;

[0022] The trimming boundary determination module is used to calculate the intersection line between interfering segmented surfaces, which serves as the trimming boundary of the target surface.

[0023] The surface trimming module is used to trim the target surface according to the trimming boundary of the target surface to obtain the trimmed surface.

[0024] A third aspect of the present invention provides a computer-readable storage medium.

[0025] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the surface trimming method based on the parametric mesh described above.

[0026] A fourth aspect of the present invention provides a computer device.

[0027] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps in the surface trimming method based on parametric meshes as described above.

[0028] A fifth aspect of the present invention provides a program product, which is a computer program product including a computer program that, when executed by a processor, implements the steps in the surface trimming method based on parametric mesh as described above.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] Before performing the intersection calculation between the target surface and the tool surface, this invention excludes as many non-interfering parts of the two surfaces as possible, focusing the calculation on the intersection position. This avoids redundant calculations on irrelevant areas, reduces the computational burden caused by the complexity of the surface, and effectively shortens the intersection calculation time between complex surfaces, thereby improving the execution efficiency of the trimming tool and increasing the calculation speed.

[0031] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0032] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0033] Figure 1This is a flowchart of the surface trimming method based on parametric mesh provided in an embodiment of the present invention;

[0034] Figure 2 This is a flowchart of surface parametric segmentation provided in an embodiment of the present invention;

[0035] Figure 3 This is a diagram showing the effect of parametric segmentation of the surface provided in an embodiment of the present invention;

[0036] Figure 4 This is a flowchart of the interference check provided in an embodiment of the present invention;

[0037] Figure 5 This is a parametric mesh effect diagram after interference checking provided in an embodiment of the present invention;

[0038] Figure 6 This is a flowchart of determining the trimming boundary provided in an embodiment of the present invention;

[0039] Figure 7 This is a cut-out effect diagram provided in an embodiment of the present invention;

[0040] Figure 8 This is the verification model provided in the embodiments of the present invention;

[0041] Figure 9 This is a schematic diagram of the surface trimming device based on parametric mesh provided in an embodiment of the present invention;

[0042] Figure 10 This is a schematic diagram of the structure of a terminal provided in an embodiment of the present invention;

[0043] Figure 11 This is a schematic diagram of the structure of a server provided in an embodiment of the present invention. Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0045] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0046] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0047] In industrial design, especially in high-precision fields such as stamping dies, complex models may consist of tens of thousands or even millions of facets. During data processing, it is necessary to store information on all facets and intermediate calculation results, resulting in a large amount of memory consumption. At the same time, the intersection calculation is the most time-consuming step in the entire cutting process, which leads to low efficiency in the intersection calculation, seriously affecting design efficiency and causing design process blockage.

[0048] Before performing the intersection calculation between the target surface and the tool surface, this invention excludes as many non-interfering parts of the two surfaces as possible, focusing the calculation on the intersection position. This avoids redundant calculations on irrelevant areas, reduces the computational burden caused by the complexity of the surface, and effectively shortens the intersection calculation time between complex surfaces, thereby improving the execution efficiency of the trimming tool and increasing the calculation speed.

[0049] Figure 1 This is a flowchart of a surface trimming method based on a parametric mesh provided in an embodiment of this application. The execution entity of this embodiment is a computer device; see [link to relevant documentation]. Figure 1 The method includes:

[0050] S101. Parametrically segment the target surface and tool surface to obtain the corresponding segmentation surface group;

[0051] The computer device acquires the target surface and the tool surface to be segmented. The surface can be a surface uploaded to the computer device by other devices, or a surface downloaded by the computer device from other devices, or a surface stored in the computer device by the user, or a surface from other sources. This application embodiment does not limit this.

[0052] After the computer obtains the target surface and tool surface to be segmented, it parametrically segments the target surface and tool surface to obtain the corresponding segmentation surface group, including: determining whether the surface to be segmented is a surface; if so, calculating the number of surface meshes; determining whether the number of surface meshes is greater than the set number; if so, segmenting the surface according to the parameter range of the surface and the set segmentation range to obtain the segmented surface group.

[0053] S102. Perform interference judgment between the segmented surface groups and exclude incoherent segmented surfaces;

[0054] When a computer device acquires a group of segmented surfaces and performs interference judgment between these groups, the target surface is denoted as F1, the tool surface as F2, and the resulting group of segmented surfaces is denoted as GF1 and GF2. The traversal number of GF1 is... i The traversal number of GF2 is jTraverse the segmentation face groups GF1 and GF2, calculate the bounding boxes of GF1[i] and GF2[j], and use the separation axis theorem to determine whether the two bounding boxes interfere. Only when the projections on all axes overlap are the two bounding boxes determined to interfere with each other, and the segmentation faces that do not interfere are excluded.

[0055] The bounding box is represented by the maximum and minimum values ​​of the face on the three-dimensional coordinate axes;

[0056] S103. Calculate the intersection line between the interfering split surfaces, which serves as the trimming boundary of the target surface;

[0057] After the computer equipment obtains the interference results between the segmented surface groups, it excludes the non-interfering segmented surfaces, calculates the intersection lines between the interfering segmented surfaces to obtain the intersection line group, checks whether the intersection lines in the intersection line group coincide, removes the coincident intersection lines to ensure that the intersection lines are unique, sorts the intersection lines, and connects the intersection lines in order according to the position of the beginning and end points of the intersection lines, and saves the processed intersection line group as the final clipping boundary.

[0058] Figure 2 This is a flowchart of surface parametric segmentation provided in an embodiment of this application. The execution entity is still a computer device; see [link to relevant documentation]. Figure 2 The target surface and tool surface are parametrically segmented to obtain the corresponding segmentation surface group, which includes the following steps:

[0059] S201. Determine whether the surface to be segmented is a surface. If it is, proceed to S202.

[0060] S202. Calculate the number of surface meshes and determine whether the number of surface meshes is greater than the set number. If so, proceed to S203.

[0061] S203. Based on the parameter range of the surface, divide the surface according to the set division range to obtain the divided surface group;

[0062] The computer equipment performs parametric segmentation on the target surface and the tool surface separately, segmenting the surface according to its parameter range (UV range). Each parametric mesh consists of multiple continuous lines. u Parameter lines (along the longitudinal direction) and v The parameter lines (along the horizontal direction) are composed of...

[0063] Each node (i,j) in the mesh corresponds to a point on the surface, and its coordinates are determined by the following formula:

[0064] ,

[0065] Where u_i and v_j are the horizontal and vertical coordinates of the parametric coordinates, and F is the surface definition function (e.g., B-spline surface or NURBS surface).

[0066] The number M of parameterized meshes on the surfaces directly determines the number of pairings required for intersection calculation. For two surfaces (assuming each surface has M parameterized meshes), it is necessary to detect whether the two surfaces intersect, which involves O(M) time complexity. 2 ) calculations. When M=10 4 When the total logarithm is 10 8 That is, approximately 100 million pairings. This logarithmic time complexity is the fundamental reason why the computation becomes difficult. Even if the detection time for each pairing is very short, for example, only microseconds of computation, 10 8 This operation may still take several hours or even longer.

[0067] Therefore, this embodiment mainly addresses the issue of excessively large numbers of parameterized meshes (more than 10). 4 The surface is segmented to avoid complicating the processing of a simple model. To maintain the mesh count of the segmented surface at 10... 4 Within this range, the parametric mesh size is set to 50, determined by the following formula:

[0068] ,

[0069] After parametric segmentation, the surface is divided into several faces according to the UV parameter lines, such as... Figure 3 The image shows the effect after parametric segmentation of the surface. The yellow grid represents the surface after parametric segmentation of the target surface; the light blue grid represents the top view of the tool surface.

[0070] Figure 4 This is a flowchart of the interference check provided in an embodiment of this application. See also... Figure 4 The specific methods for judging interference between segmented surface groups include:

[0071] In this embodiment, the target surface is denoted as F1, the tool surface as F2, and the corresponding segmented surface groups are denoted as GF1 and GF2, where the traversal number of GF1 is... i The traversal number of GF2 is j Traverse the segmentation face groups GF1 and GF2, calculate the bounding boxes of GF1[i] and GF2[j], and use the separation axis theorem to determine whether the two bounding boxes interfere. Only when the projections on all axes overlap are the two bounding boxes determined to interfere with each other, and the segmentation faces that do not interfere are excluded.

[0072] The bounding box is represented by the maximum and minimum values ​​of the face on the three-dimensional coordinate axes;

[0073] S401, Calculate the bounding box B1 of GF1[i];

[0074] The resulting bounding box B1 is denoted as:

[0075] P1min(X1min,Y1min,Z1min),

[0076] P1max(X1max,Y1max,Z1max),

[0077] Where P1min represents the minimum point of bounding box B1, P1max represents the maximum point of bounding box B1, (X1min, Y1min, Z1min) represents the coordinate value of the minimum point (i.e., P1min) under the three-dimensional coordinate axis, and (X1max, Y1max, Z1max) represents the coordinate value of the maximum point (i.e., P1max) under the three-dimensional coordinate axis.

[0078] S402, Calculate the bounding box B2 of GF2[j];

[0079] The resulting bounding box B2 is denoted as:

[0080] P2min(X2min,Y2min,Z2min),

[0081] P2max(X2max,Y2max,Z2max),

[0082] Where P2min represents the minimum point of bounding box B2, P2max represents the maximum point of bounding box B2, (X2min,Y2min,Z2min) represents the coordinate value of the minimum point (i.e., P2min) under the three-dimensional coordinate axis, and (X2max,Y2max,Z2max) represents the coordinate value of the maximum point (i.e., P2max) under the three-dimensional coordinate axis.

[0083] S403. Use the separation axis theorem to determine whether two bounding boxes interfere with each other. Only when the projections on all axes overlap can it be determined that the two bounding boxes interfere with each other, and the non-interfering dividing surfaces are excluded.

[0084] The projection range of bounding box B1 on the X-axis is [X1min, X1max], the projection range on the Y-axis is [Y1min, Y1max], and the projection range on the Z-axis is [Z1min, Z1max]. The projection range of bounding box B2 on the X-axis is [X2min, X2max], the projection range on the Y-axis is [Y2min, Y2max], and the projection range on the Z-axis is [Z2min, Z2max]. We determine whether the projection ranges of B1 and B2 overlap on the X-axis, Y-axis, and Z-axis. If the projection ranges of bounding boxes B1 and B2 overlap on all three axes, they are considered to be interfering. If the projection ranges on at least one axis do not overlap, they are considered to be not interfering.

[0085] Specifically, it includes the following steps:

[0086] S4031, Determine if X1max is satisfied.<X2min||X1min> If X2max is satisfied, it is determined that the two bounding boxes do not interfere with each other, and the next step of judgment is performed;

[0087] Among them, X1max<X2min||X1min> X2max represents the projection range of bounding box B1 on the X-axis as [X1min, X1max], and the projection range of bounding box B2 on the X-axis as [X2min, X2max]. When the maximum value (X1max) of bounding box B1 on the X-axis is smaller than the minimum value (X2min) of bounding box B2 on the X-axis, it means that the two projection ranges do not overlap. Similarly, when the minimum value (X1min) of bounding box B1 on the X-axis is larger than the maximum value (X2max) of bounding box B2 on the X-axis, it means that the two projection ranges do not overlap.

[0088] S4032, Determine if Y1max is satisfied.<Y2min||Y1min> If Y2max is satisfied, it is determined that the two bounding boxes do not interfere with each other, and the next step of judgment is performed;

[0089] Among them, Y1max<Y2min||Y1min> Y2max represents the projection range of bounding box B1 on the Y-axis as [Y1min, Y1max], and the projection range of bounding box B2 on the Y-axis as [Y2min, Y2max]. When the maximum value (Y1max) of bounding box B1 on the Y-axis is smaller than the minimum value (Y2min) of bounding box B2 on the Y-axis, it means that the two projection ranges do not overlap. Similarly, when the minimum value (Y1min) of bounding box B1 on the Y-axis is larger than the maximum value (Y2max) of bounding box B2 on the Y-axis, it means that the two projection ranges do not overlap.

[0090] S4033, Determine if Z1max is satisfied.<Z2min||Z1min> If Z2max is satisfied, it is determined that the two bounding boxes do not interfere; otherwise, the bounding boxes interfere with each other.

[0091] Among them, Z1max<Z2min||Z1min> Z2max represents the projection range of bounding box B1 on the Z-axis as [Z1min, Z1max], and the projection range of bounding box B2 on the Z-axis as [Z2min, Z2max]. When the maximum value (Z1max) of bounding box B1 on the Z-axis is smaller than the minimum value (Z2min) of bounding box B2 on the Z-axis, it means that the two projection ranges do not overlap. Similarly, when the minimum value (Z1min) of bounding box B1 on the Z-axis is larger than the maximum value (Z2max) of bounding box B2 on the Z-axis, it means that the two projection ranges do not overlap.

[0092] Figure 5 The parametric mesh effect diagram after interferometry is shown below. Figure 5 As shown, in the results after the interference check, the red grid represents the dividing surface that is determined to be interference.

[0093] Figure 6 This is a flowchart illustrating the determination of the trimming boundary provided in an embodiment of this application. See also... Figure 6 The calculation of the intersection line between the interfering surfaces, which serves as the clipping boundary of the target surface, specifically includes:

[0094] S601. Calculate the intersection lines between the interference surfaces to obtain the intersection line set;

[0095] In this embodiment, the intersection line between the interfering planes (GF1[i] and GF2[j]) is calculated to obtain the intersection line group GC;

[0096] S602. Check whether the intersection lines in the intersection line group overlap, remove overlapping intersection lines, and ensure that the intersection lines are unique.

[0097] S603. Sort the intersection lines and connect them sequentially according to the positions of their starting and ending points;

[0098] S604. Save the processed intersection group as the final trimming boundary.

[0099] Figure 7 The result of the cropping is shown in Figure 7. After determining the cropping boundary, the target surface is cropped according to the boundary.

[0100] The method of this invention was used to validate a scenario with a complex target surface. The number of parameterized meshes exceeded 56,000. The final validation model is as follows. Figure 8 As shown, the purple surface is the target surface, and the green surface is the tool surface;

[0101] Verification results show that without reducing the number of parametric meshes, the clipping execution time is 88 seconds; after using the method of this invention, the clipping execution time is reduced to 9 seconds. The execution efficiency is greatly improved, effectively enhancing the designer's work efficiency and iteration speed.

[0102] Figure 9 This is a schematic diagram of the surface trimming device based on a parametric mesh provided in an embodiment of this application. See also... Figure 9 The device includes:

[0103] The surface segmentation module 901 is used to parametrically segment the target surface and the tool surface to obtain the corresponding segmentation surface group;

[0104] Interference checking module 902 is used to judge the interference between the segmented surface groups and exclude incoherent segmented surfaces;

[0105] The trimming boundary determination module 903 is used to calculate the intersection line between the interfering segmented surfaces, which serves as the trimming boundary of the target surface.

[0106] The surface trimming module 904 is used to trim the target surface according to the trimming boundary of the target surface to obtain the trimmed surface.

[0107] Figure 10 A schematic diagram of the structure of a terminal 1000 provided in an exemplary embodiment of this application is shown. The terminal 1000 can be used to perform the steps executed by the computer device in the above-described surface trimming method based on parametric meshes.

[0108] Typically, terminal 1000 includes a processor 1001 and a memory 1002.

[0109] Processor 1001 may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. Processor 1001 may be implemented using at least one hardware form selected from DSP (Digital Signal Processing), FPGA (Field Programmable Gate Array), and PLA (Programmable Logic Array). Processor 1001 may also include a main processor and a coprocessor. The main processor, also known as a CPU (Central Processing Unit), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 1001 may integrate a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, processor 1001 may also include an AI (Artificial Intelligence) processor, which is used to handle computational operations related to machine learning.

[0110] The memory 1002 may include one or more computer-readable storage media, which may be non-transitory. The memory 1002 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory 1002 are used to store at least one instruction, which is used by the processor 1001 to implement the parametric mesh-based surface trimming method provided in the method embodiments of this application.

[0111] In some embodiments, the device 1000 may also optionally include a peripheral device interface 1003 and at least one peripheral device. The processor 1001, memory 1002, and peripheral device interface 1003 can be connected via a bus or signal line. Each peripheral device can be connected to the peripheral device interface 1003 via a bus, signal line, or circuit board.

[0112] Those skilled in the art will understand that Figure 10 The structure shown does not constitute a limitation on terminal 1000 and may include more or fewer components than shown, or combine certain components, or use different component arrangements.

[0113] Figure 11 This is a schematic diagram of a server structure provided in an embodiment of this application. The server 1100 can vary significantly due to different configurations or performance. It may include one or more Central Processing Units (CPUs) 1101 and one or more memories 1102. The memories 1102 store at least one instruction, which is loaded and executed by the processor 1101 to implement the methods provided in the various method embodiments described above. Of course, the server 1100 may also have wired or wireless network interfaces, a keyboard, and input / output interfaces for input and output. The server may also include other components for implementing device functions, which will not be elaborated upon here.

[0114] Server 1100 can be used to perform the steps executed by the computer device in the above-described parametric mesh-based surface trimming method.

[0115] This application also provides a computer device for a surface trimming method based on a parametric mesh. The computer device includes a processor and a memory. The memory stores at least one instruction, which is loaded and executed by the processor to implement the surface trimming method based on a parametric mesh described above.

[0116] This application also provides a computer program product including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the aforementioned surface trimming method based on a parametric mesh.

[0117] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0118] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A surface trimming method based on parametric meshes, characterized in that, Applied to CAD design, specifically stamping die design, it includes the following steps: Obtain the target surface and tool surface to be segmented, parameterize the target surface and tool surface to be segmented, and obtain the corresponding segmentation surface group; Interference judgment is performed between the segmented surface groups to exclude incoherent segmented surfaces; wherein, interference judgment between the segmented surface groups includes: Let the target surface be denoted as F1, the tool surface as F2, and the corresponding segmented surface groups as GF1 and GF2, where the traversal number of GF1 is... i The traversal number of GF2 is j Traverse the segmentation face groups GF1 and GF2, calculate the bounding boxes of GF1[i] and GF2[j], and use the separation axis theorem to determine whether the two bounding boxes interfere. Only when the projections on all axes overlap are the two bounding boxes determined to interfere with each other, and the segmentation faces that do not interfere are excluded. Calculate the intersection line between the interfering split surfaces, which serves as the clipping boundary of the target surface; The target surface is trimmed according to the trimming boundary to obtain the trimmed surface.

2. The surface trimming method based on parametric mesh as described in claim 1, characterized in that, The parameterized target surface and tool surface are used to obtain a corresponding set of segmentation surfaces, including: Determine whether the surface to be segmented is a surface. If it is, calculate the number of surface meshes and determine whether the number of surface meshes is greater than the set number. If so, segment the surface according to the parameter range of the surface and the set segmentation range to obtain the segmented surface group.

3. The surface trimming method based on parametric mesh as described in claim 2, characterized in that, When dividing the surface according to its UV range, each parametric mesh consists of multiple continuous lines along the longitudinal direction. u Parameter lines and along the horizontal v Composition of parameter lines.

4. The surface trimming method based on parametric mesh as described in claim 1, characterized in that, The separation axis theorem is used to determine whether two enclosed boxes interfere with each other, including: Determine whether the projection ranges of the two bounding boxes overlap on the X-axis, Y-axis, and Z-axis respectively. If the projection ranges of bounding boxes B1 and B2 overlap on the X-axis, Y-axis, and Z-axis, it is determined that the two bounding boxes interfere with each other. If the projection ranges of at least one axis do not overlap, it is determined that the two bounding boxes do not interfere with each other.

5. The surface trimming method based on parametric mesh as described in claim 1, characterized in that, The intersection line between the segmented surfaces of the calculated interference, serving as the clipping boundary of the target surface, includes: Calculate the intersection lines between the interfering split surfaces to obtain a set of intersection lines. Check whether the intersection lines in the set coincide and remove the coincident intersection lines to ensure that the intersection lines are unique. Sort the intersection lines and connect them in order according to the position of the beginning and end points of the intersection lines. Save the processed set of intersection lines as the final trimming boundary.

6. A surface trimming device based on parametric meshes, characterized in that, Applied to CAD design, specifically stamping die design, including: The surface segmentation module is used to parametrically segment the target surface and the tool surface to obtain the corresponding segmentation surface group; The interference checking module is used to determine interference between groups of segmented surfaces and exclude incoherent segmented surfaces. The interference determination between groups of segmented surfaces includes: Let the target surface be denoted as F1, the tool surface as F2, and the corresponding segmented surface groups as GF1 and GF2, where the traversal number of GF1 is... i The traversal number of GF2 is j Traverse the segmentation face groups GF1 and GF2, calculate the bounding boxes of GF1[i] and GF2[j], and use the separation axis theorem to determine whether the two bounding boxes interfere. Only when the projections on all axes overlap are the two bounding boxes determined to interfere with each other, and the segmentation faces that do not interfere are excluded. The trimming boundary determination module is used to calculate the intersection line between interfering segmented surfaces, which serves as the trimming boundary of the target surface. The surface trimming module is used to trim the target surface according to the trimming boundary of the target surface to obtain the trimmed surface.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the surface trimming method based on parametric mesh as described in any one of claims 1-5.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the surface trimming method based on parametric mesh as described in any one of claims 1-5.

9. A program product, said program product being a computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps in the surface trimming method based on parametric mesh as described in any one of claims 1-5.

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