CN-121982252-A - Automatic flattening method and system for three-dimensional long-sleeve grid model

CN121982252ACN 121982252 ACN121982252 ACN 121982252ACN-121982252-A

Abstract

The invention belongs to the technical field of clothing reverse design, and provides an automatic flattening method and an automatic flattening system of a three-dimensional long-sleeve grid model, wherein the automatic flattening method of the three-dimensional long-sleeve grid model comprises the following steps of preprocessing the three-dimensional long-sleeve grid model; detecting boundaries of the three-dimensional long-sleeve grid model, determining double boundaries, setting double-layer traversal on the double boundaries, calculating geodesic distances between every two vertexes in the double boundaries, sorting the geodesic distances from small to large, screening out n groups of vertex combinations with minimum geodesic distances, converting geodesic wires corresponding to the n groups of vertex combinations into automatic cutting lines, cutting the three-dimensional long-sleeve grid model, measuring area variation of triangles in the flattened model after cutting, determining an optimal cutting scheme, and finishing flattening of the three-dimensional long-sleeve grid model.

Inventors

DING WUJIE
XU HAIYAN
Gao Haiwang
QIAN KEFENG

Assignees

卓尚服饰(杭州)有限公司

Dates

Publication Date: 20260505
Application Date: 20260122

Claims (10)

1. An automatic flattening method of a three-dimensional long-sleeve grid model is characterized by comprising the following steps of: S1, preprocessing a three-dimensional long-sleeve grid model; S2, detecting the boundary of the three-dimensional long-sleeve grid model, and determining a double boundary; S3, double-layer traversal is set for the double boundaries, and the geodesic distance between every two vertexes in the double boundaries is calculated; s4, sorting the geodesic distances from small to large, and screening out n groups of vertex combinations with minimum geodesic distances; s5, converting the geodesic wires corresponding to the n groups of vertex combinations into automatic cutting lines, and cutting the three-dimensional long-sleeve grid model; And S6, measuring the area variation of the triangle in the flattened model after cutting, determining an optimal cutting scheme and finishing flattening of the three-dimensional long-sleeve grid model.
2. The method for automatically flattening a three-dimensional long-sleeve mesh model according to claim 1, wherein the preprocessing includes small micro-hole filling and triangle area homogenization; The small micropore holes are filled with cuff holes and sleeve root holes of a three-dimensional long-sleeve grid model, and the rest small holes of the model are filled; The triangle area homogenization is realized by gradually adding vertexes, so that all triangle areas in the model are in a preset small range, and the triangle areas are similar.
3. The method according to claim 1, wherein the boundary detection is to screen vertices of a cuff portion and a cuff root portion of the three-dimensional long-sleeve mesh model as boundary points of a cuff boundary and a cuff root boundary, respectively, and the double boundaries are a cuff root boundary and a cuff root boundary.
4. The method of claim 1, wherein the bi-layer traversal is implemented by logic comprising: The number of the vertexes in the cuff boundary) traversing all vertexes in the cuff boundary to the number of the vertexes in the cuff boundary) traversing the number of the vertexes in the cuff boundary to calculate the geodesic distance from vertex to vertex ; The geodesic distance is the smallest path along which the vertices or edges of the three-dimensional long-sleeve mesh model move from one boundary point to another, and the path is composed of a plurality of vertex connecting lines.
5. The automatic flattening method of a three-dimensional long-sleeve grid model according to claim 1, wherein the area variation is measured as areas of all triangles before and after flattening of the calculation model, absolute values of area variation of each triangle are calculated and accumulated based on the number of the triangles before and after flattening and the characteristic of unchanged topological structure, and a cutting scheme with the minimum absolute value of the total area variation is determined as an optimal cutting scheme; The area variation is the area variation percentage of all triangles before and after the long-sleeve grid model is flattened.
6. An automatic flattening system of a three-dimensional long-sleeve grid model is applied to the automatic flattening method of the three-dimensional long-sleeve grid model according to any one of claims 1-5, and is characterized by comprising a preprocessing module, a boundary detection module, a geodesic calculation module, a screening module, a cutting module and a flattening optimization module, wherein the modules work cooperatively to complete the whole process from preprocessing to flattening of a two-dimensional template of the three-dimensional long-sleeve grid model.
7. The automatic flattening system of a three-dimensional long-sleeve mesh model of claim 6, wherein the preprocessing module includes a hole filling unit and an area homogenizing unit; the hole filling unit is used for reserving the sleeve openings and sleeve root holes and filling the rest tiny holes of the model; the area homogenizing unit is used for gradually adding vertexes to enable all triangle areas in the model to be in a preset small range and similar.
8. The system for automatically flattening a three-dimensional long-sleeve mesh model according to claim 6, wherein the boundary detection module is configured to screen vertices of a cuff portion and a cuff root portion of the three-dimensional long-sleeve mesh model, labeled as a cuff boundary and a cuff root boundary, respectively; The geodesic calculation module is used for calculating the geodesic distance between every two boundary vertexes through double-layer traversal logic.
9. The system for automatically flattening a three-dimensional long-sleeve mesh model of claim 6, wherein the screening module is configured to sort geodesic distances and screen out n groups of vertex combinations with minimum geodesic distances; The cutting module is used for converting the screened geodesic wire into an automatic cutting wire, deleting the vertex related to the cutting wire and converting the semi-closed model into a completely-open flatly-flattening model.
10. The automatic flattening system of a three-dimensional long-sleeve mesh model according to claim 6, wherein the flattening optimization module is configured to calculate the area variation of the triangle before and after flattening the model, screen out an optimal cutting scheme with the minimum absolute value of the total area variation, and complete final flattening of the three-dimensional long-sleeve mesh model based on the optimal cutting scheme.

Description

Automatic flattening method and system for three-dimensional long-sleeve grid model Technical Field The invention belongs to the technical field of garment reverse design, and particularly relates to an automatic flattening method and system of a three-dimensional long-sleeve grid model. Background In the fields of three-dimensional garment digitization, computer graphics and garment intelligent manufacturing, the cutting treatment of a three-dimensional garment model (particularly a model with a triangular mesh as a core representation form) is a key technology for connecting downstream links such as garment digitization design, entity production, virtual fitting and the like. The long sleeve is used as a core functional component of the garment, the structure of the long sleeve has obvious specificity, namely the long sleeve is required to be matched with the natural form of the human arm, the long sleeve comprises a plurality of characteristic areas such as sleeve caps, sleeve bodies, cuffs, sleeve seams and the like, the curved surface curvatures and topological structures of the long sleeves of different styles (such as straight sleeves, horn sleeves and bubble sleeves) have obvious differences, and strict requirements are provided for cutting precision, cutting line rationality and automation degree. Currently, a cutting technology of a three-dimensional triangular mesh model has been developed, but automatic cutting for a specific target of a long sleeve still faces a plurality of bottlenecks. In the prior art, most cutting schemes are biased to generalized grid cutting, and structural characteristics of the long sleeves are not fully considered, so that a plurality of problems exist in practical application: The traditional automatic cutting algorithm performs cutting path planning based on grid geometric information (such as vertex distance and surface normal vector), the structural characteristics of long sleeves cannot be accurately combined, key process characteristics of sleeve curves, sleeve seams and the like are difficult to identify, cutting lines deviate from clothing process requirements, a large amount of manual adjustment is needed to be input subsequently to meet sheet unfolding, typesetting and production requirements, and the clothing digital production efficiency is seriously affected; The partial cutting scheme depends on manual preset cutting paths or marked characteristic points, has extremely low automation degree, cannot adapt to the requirements of rapid cutting and flattening of the long-sleeve grid models with different styles and sizes in the mode of garment customization and small-batch production, and greatly limits the flexibility and response speed of garment digital production; The cutting of the long-sleeve triangle mesh model needs to take account of mesh topological consistency, so that the problems of cracks, redundant vertexes, surface missing and the like after cutting are avoided, but when the special parts with complex curved surface characteristics are processed by the conventional general cutting algorithm, the topological stability is insufficient, the defects are easy to occur after cutting, the flattening effect and the normal promotion of downstream procedures (such as template stitching and virtual fitting) are further influenced, and the landing application of the three-dimensional garment digitizing technology is restricted; there is a need for an automatic flattening method and system for three-dimensional long-sleeve mesh models to solve the above-mentioned problems. Disclosure of Invention The invention aims to provide an automatic flattening method and system for a three-dimensional long-sleeve grid model, which are used for solving the problems in the background technology. In order to achieve the purpose, the invention provides the following technical scheme that the automatic flattening method of the three-dimensional long-sleeve grid model comprises the following steps of: S1, preprocessing a three-dimensional long-sleeve grid model; S2, detecting the boundary of the three-dimensional long-sleeve grid model, and determining a double boundary; S3, double-layer traversal is set for the double boundaries, and the geodesic distance between every two vertexes in the double boundaries is calculated; s4, sorting the geodesic distances from small to large, and screening out n groups of vertex combinations with minimum geodesic distances; s5, converting the geodesic wires corresponding to the n groups of vertex combinations into automatic cutting lines, and cutting the three-dimensional long-sleeve grid model; And S6, measuring the area variation of the triangle in the flattened model after cutting, determining an optimal cutting scheme and finishing flattening of the three-dimensional long-sleeve grid model. According to a further technical scheme, the pretreatment comprises filling of small micro-holes and homogenization of triangular areas; The small