Knitwear simulation using yarn modeling

Abstract

A garment simulation method and apparatus are disclosed. A garment simulation method relating to knitwear according to one embodiment includes the steps of: adding a margin mesh to a garment pattern corresponding to the knitwear and extending the garment pattern; mapping the vertices of yarn corresponding to the knitwear to the mesh of the extended garment pattern; and generating rendering information of the knitwear by simulating the garment pattern in which the yarn is arranged based on the mapping relationship between the vertices and the mesh of the garment pattern.

Description

[Technical Field]

[0001] The following embodiments relate to a garment simulation method and apparatus, and more specifically, to a garment simulation method and apparatus relating to knitwear. [Background technology]

[0002] Although clothing appears three-dimensional when worn by a person, it is actually closer to two-dimensional because it is a combination of fabrics cut according to two-dimensional patterns. Because the fabrics used for clothing are flexible, their form changes in diverse ways depending on the shape and movement of the wearer's body. Furthermore, fabrics possess various physical properties, such as strength, elasticity, and shrinkage rate. Differences in these properties can lead to different appearances and feels even for garments of the same design. Computer-based clothing simulation technology is widely used in the fashion industry to develop actual clothing designs. Therefore, there is a need for the development of clothing simulation technology that realistically represents clothing according to its material. [Overview of the project] [Means for solving the problem]

[0003] A garment simulation method relating to knitwear according to one embodiment includes the steps of: adding a margin mesh to a garment pattern corresponding to the knitwear and extending the garment pattern; mapping the vertices of yarn corresponding to the knitwear to the mesh of the extended garment pattern; and generating rendering information of the knitwear by simulating the garment pattern on which the yarn is arranged based on the mapping relationship between the vertices and the mesh of the garment pattern.

[0004] The step of mapping the vertex to the mesh of the extended garment pattern may include: obtaining parameters corresponding to the deformation state of the material space corresponding to the garment pattern; interpolating pre-calculated displacements based on the parameters corresponding to the deformation state samples to obtain the displacement of the vertex corresponding to the parameters; and determining the position of the vertex in the material space corresponding to the deformation state based on the obtained displacement.

[0005] The step of generating rendering information for the knitwear may include the steps of: obtaining the world space position of the vertex corresponding to the knitwear based on the position of the vertex in material space corresponding to the deformation state; and generating rendering information for the knitwear based on the obtained world space position.

[0006] The margin mesh can be added to the area outside the boundary of the garment pattern with a certain width.

[0007] The step of extending the garment pattern may include adding the margin mesh, which has a curvature of a certain size, to the garment pattern corresponding to the knitwear.

[0008] The step of extending the garment pattern may include the step of adding the margin mesh to the garment pattern based on the physical property data of the knitwear.

[0009] The physical property data of the knitwear may include at least one of the following: setting information on whether or not to add the margin mesh, size information of the region where the margin mesh is generated, and curvature information of the margin mesh.

[0010] The vertex may include at least one vertex located on the centerline of the yarn.

[0011] The steps for generating rendering information for the knitwear may include: tessellating the centerlines of the yarn with a cylinder mesh; and simulating the garment pattern on which the tessellated yarn is placed, based on the mapping relationship between the vertices and the mesh of the garment pattern, thereby generating rendering information for the knitwear.

[0012] The step of mapping the vertex to the mesh of the extended garment pattern may include copying the vertex of the yarn mapped to the area where the first mesh and the second mesh overlap in the garment pattern, and mapping each of the copied vertex to the first mesh and the second mesh.

[0013] The first mesh and the second mesh may be included in the margin mesh.

[0014] The step of mapping the vertex to the mesh of the extended garment pattern may include moving the vertex of the yarn located outside the extended garment pattern onto the boundary line of the extended garment pattern.

[0015] The step of mapping the vertex to the mesh of the extended garment pattern may include the steps of rotating the yarn based on directional information of the knit structure corresponding to the knitwear, and mapping the vertex of the rotated yarn to the mesh of the extended garment pattern.

[0016] An electronic device according to an embodiment includes at least one processor including processing circuitry; and a memory storing instructions, which, when executed individually or collectively by the at least one processor, cause the electronic device to add a margin mesh to a clothing pattern corresponding to the knitwear and extend the clothing pattern; map vertices of yarns corresponding to the knitwear to the mesh of the extended clothing pattern; and generate rendering information of the knitwear by simulating the clothing pattern in which the yarns are arranged based on the mapping relationship between the vertices and the mesh of the clothing pattern.

[0017] The operation of mapping the vertices to the mesh of the extended clothing pattern can include obtaining parameters corresponding to the deformed state of the material space corresponding to the clothing pattern; interpolating displacements pre-calculated based on the parameters corresponding to the deformed state samples to obtain the displacements of the vertices corresponding to the parameters; and determining the positions of the vertices in the material space corresponding to the deformed state based on the obtained displacements.

[0018] The operation of generating the rendering information of the knitwear can include obtaining the positions of the vertices in the world space corresponding to the knitwear based on the positions of the vertices in the material space corresponding to the deformed state; and generating the rendering information of the knitwear based on the obtained positions in the world space.

[0019] The operation of extending the clothing pattern can include adding the margin mesh with a curvature of a certain size set to the clothing pattern corresponding to the knitwear.

[0020] The operation of extending the clothing pattern may include the operation of adding the margin mesh to the clothing pattern based on the physical property data of the knitted wear.

[0021] The physical property data of the knitted wear may include at least one of setting information on whether to add the margin mesh, size information on the area where the margin mesh is generated, and curvature information of the margin mesh.

[0022] The operation of generating the rendering information of the knitted wear includes the operation of tessellating the center line of the yarn with a cylinder mesh; and the operation of generating the rendering information of the knitted wear by simulating the clothing pattern in which the tessellated yarn is arranged based on the mapping relationship between the vertex and the mesh of the clothing pattern.

[0023] The operation of mapping the vertex to the mesh of the extended clothing pattern may include copying the vertex of the yarn mapped to the area where the first mesh and the second mesh overlap in the clothing pattern, and mapping each of the copied vertices to the first mesh and the second mesh.

Brief Description of the Drawings

[0024] [Figure 1] FIG. 1 is an operation flowchart of a clothing simulation method for knitted wear according to an embodiment. [Figure 2a] FIG. 2a is a diagram for explaining an area where a margin mesh is added to a clothing pattern according to an embodiment. [Figure 2b] FIG. 2b is a diagram for explaining an area where a margin mesh is added to a clothing pattern according to an embodiment. [Figure 3a]Figure 3a is a diagram illustrating the operation of mapping each copied vertex according to one embodiment to a first mesh and a second mesh that overlap each other. [Figure 3b] Figure 3b illustrates the operation of mapping each of the copied vertices according to one embodiment to a first mesh and a second mesh that overlap each other. [Figure 3c] Figure 3c illustrates the operation of mapping each copied vertex to a first mesh and a second mesh that overlap each other, according to one embodiment. [Figure 4a] Figure 4a illustrates the operation of adjusting the position of the yarn vertex mapped to the outside of a garment pattern according to one embodiment. [Figure 4b] Figure 4b illustrates the operation of adjusting the position of the yarn vertex mapped to the outside of a garment pattern according to one embodiment. [Figure 5a] Figure 5a is a diagram illustrating the shape of knitwear based on directional information of a knit structure according to one embodiment. [Figure 5b] Figure 5b is a diagram illustrating the shape of knitwear based on directional information of a knit structure according to one embodiment. [Figure 5c] Figure 5c is a diagram illustrating the shape of knitwear based on directional information of a knit structure according to one embodiment. [Figure 6] Figure 6 illustrates a user interface screen for setting physical property data of knitwear according to one embodiment. [Figure 7a] Figure 7a is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 7b] Figure 7b is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 7c] Figure 7c is a diagram illustrating a yarn-based knitting simulation method according to one embodiment. [Figure 8]Figure 8 is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 9a] Figure 9a is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 9b] Figure 9b is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 9c] Figure 9c is a diagram illustrating a yarn-based knitting simulation method according to one embodiment. [Figure 9d] Figure 9d is a diagram illustrating a yarn-based knitting simulation method according to one embodiment. [Figure 9e] Figure 9e is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 10] Figure 10 is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 11] Figure 11 is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 12] Figure 12 is a diagram illustrating a knitting simulation method for a yarn base according to one embodiment. [Figure 13] Figure 13 is an illustrative diagram of the configuration of an electronic device according to one embodiment. [Modes for carrying out the invention]

[0025] The specific structural or functional descriptions of the embodiments are disclosed for illustrative purposes only and can be implemented in various modified forms. Therefore, the actual implemented forms are not limited to the specific embodiments disclosed, and the scope of this specification includes modifications, equivalents, or substitutions of the technical ideas described in the embodiments.

[0026] In relation to the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of the noun corresponding to an item may include one or more of the items unless otherwise indicated to be clearly different in the relevant context.

[0027] In this document, each phrase such as "A or B," "at least one of A and B," "at least one of A or B," "A, B or C," "at least one of A, B and C," and "at least one of A, B, or C" may include any one of the items listed together with the phrase, or any possible combination thereof.

[0028] Terms such as “first,” “second,” “initial,” or “second” are used simply to distinguish one component from another and do not limit it to other aspects (e.g., importance or order). For example, the first component may be named the second component, and similarly the second component may be named the first component.

[0029] When any (e.g., the first) component is referred to as "coupled" or "connected" to another (e.g., the second) component, with or without the terms "functionally" or "communically," it means that the first component may be connected to the other component directly (e.g., by wire), wirelessly, or via the third component.

[0030] Unless the context clearly indicates otherwise, singular expressions include plural expressions. In this specification, terms such as “includes” or “has” are intended to specify the existence of the described features, figures, steps, actions, components, parts, or combinations thereof, and should be understood not to preemptively exclude the possibility of the existence or addition of one or more other features, figures, steps, actions, components, parts, or combinations thereof.

[0031] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as those generally understood by those of ordinary skill in the art. Commonly used, predefined terms should be interpreted as having the meaning consistent with their meaning in the context of the relevant art, and not as ideal or overly formal unless expressly defined herein.

[0032] The embodiments will be described in detail below with reference to the attached drawings. In the description with reference to the attached drawings, the same reference numerals will be used for the same components, regardless of the reference numerals in the drawings, and redundant explanations will be omitted.

[0033] Figure 1 is an operation flowchart of a garment simulation method for knitwear according to one embodiment.

[0034] The operations in steps 110 to 130 of the garment simulation method for knitwear, as described with reference to Figure 1, are performed in order, but not necessarily in sequence. For example, the order of steps 110 to 130 may be changed, and at least two steps may be performed in parallel.

[0035] The garment simulation method for knitwear, as described with reference to Figure 1, may also be performed using an electronic device. The specific hardware structure of the electronic device will be described in detail below.

[0036] A garment simulation method relating to knitwear according to one embodiment will be referred to simply as "the method" or "garment simulation method" below.

[0037] Generally, a garment pattern refers to a paper template used to cut material when manufacturing clothing. In this specification, a garment pattern refers to a two-dimensional planar garment pattern fragment virtually manufactured by a computer program. For example, a garment pattern is used to manufacture virtual clothing that a user intends to drape onto a three-dimensional avatar. More than one garment pattern may be used to manufacture a single garment.

[0038] A garment pattern according to one embodiment may be a virtual two-dimensional garment pattern modeled as a sum of numerous polygonal meshes for the simulation of a three-dimensional virtual garment. Each vertex of the mesh is a point mass, and each edge of the mesh may be represented as an elastic spring connecting the vertex masses. The garment pattern may be modeled, for example, by a Mass-Spring Model, where the spring has resistance values ​​to stretch, shear, and bending, depending on the properties of the fabric used. Each vertex moves due to the action of external forces such as gravity and internal forces of stretch, shear, and bending. By calculating the external and internal forces to determine the forces acting on each vertex, the displacement and velocity of movement of each vertex can be obtained. The movement of the virtual garment may then be simulated through the movement of the mesh vertices at each time step. By dressing a 3D object (e.g., an avatar) with a 2D virtual clothing pattern consisting of triangular meshes, it is possible to create 3D virtual clothing with a natural shape based on the laws of physics.

[0039] The complex geometric structure of knitted fabric can induce visual and physical complexity during the rendering or simulation process. One embodiment of the method includes a method for simulating a virtual garment composed of knitted fabric created by knitting or crossing yarns. A virtual garment composed of knitted fabric is referred to as knitwear.

[0040] A garment simulation method according to one embodiment includes step 110 of adding a margin mesh to a garment pattern corresponding to knitwear and extending the garment pattern. The margin mesh includes a mesh added to the region outside the boundary of the garment pattern. For example, the margin mesh may be added to the region outside the boundary of the garment pattern with a certain width. The addition of the margin mesh can extend the edge region of the garment pattern.

[0041] For example, referring to Figure 2a, a margin mesh may be added to the outer region 220 of the boundary of the garment pattern 210. The size of the outer region 220 to which the margin mesh is added is determined to be a fixed size. Alternatively, the size of the outer region 220 to which the margin mesh is added may be determined by user input.

[0042] According to one embodiment, a margin mesh can be added to the outer region of the garment pattern boundary that is sewn with other garment patterns. In other words, a margin mesh may be added to the seam allowance region of the garment pattern's seam line. For example, referring to Figure 2b, if the first boundary line 231, the second boundary line 232, and the third boundary line 233 of the garment pattern 230 correspond to seam lines that are sewn with other garment patterns, and the fourth boundary line 234 does not correspond to a seam line, then a margin mesh may be added to the outer region 240 of the first boundary line 231, the second boundary line 232, and the third boundary line 233. The end region of the fourth boundary line 234 is not extended.

[0043] By adding a margin mesh, it is possible to prevent gaps or empty spaces from occurring in the sewing lines where garment patterns are connected in a virtual garment.

[0044] Referring again to Figure 1, according to one embodiment, step 110 of extending the garment pattern includes adding a margin mesh to the garment pattern corresponding to the knitwear, which has a curvature of a certain size. The margin mesh added to the garment pattern has a curvature of a certain size. When the garment including the garment pattern is rendered or simulated, the fabric corresponding to the margin mesh is set to curve in the direction of the garment. For example, the curvature of the margin mesh may be set to curve in the opposite direction to the normal vector of the garment pattern in the simulated virtual garment.

[0045] According to one embodiment, step 110 of extending the garment pattern includes adding a margin mesh to the garment pattern based on the physical properties data of the knitwear. The physical properties data of the knitwear is information that indicates the physical properties of the knitwear, and may include, for example, at least one of the following: stitching type information of the knitwear, gauge information of the knitwear, direction information of the knit structure, yarn thickness information, yarn color information, setting information on whether or not to add a margin mesh to the knitwear, size information of the area where the margin mesh is generated (or the seam allowance area), and curvature information of the margin mesh. The physical properties data of the knitwear will be described in detail below.

[0046] A garment simulation method according to one embodiment includes step 120 of mapping the vertex of a yarn corresponding to knitwear to a mesh of an extended garment pattern. The vertex of the yarn may include at least one vertex located on the yarn's centerline. For example, the yarn may be modeled with edges connecting adjacent vertex located at regular intervals on the yarn's centerline. For example, it may be modeled with discrete elastic rods. The modeling of the yarn will be described in detail below.

[0047] The yarn can be represented by an extended garment pattern mesh that includes both the mesh originally included in the garment pattern and the margin mesh added in step 110. Mapping the yarn vertices to the extended garment pattern mesh means determining the position of each yarn vertex that makes up the knitwear on the garment pattern. Mapping the yarn vertices to the extended garment pattern mesh means storing the position of each yarn vertex on the garment pattern as a positional relationship with the garment pattern mesh. Each yarn vertex may be placed at the mapped position on the garment pattern. As will be explained in detail below, once the garment, including the garment pattern, is simulated, the yarn can be placed at the mapped position on the garment pattern and simulated based on the mesh.

[0048] According to one embodiment, step 120, which maps the vertex of the yarn to the mesh of the extended garment pattern, includes a step of determining the position of the yarn in the material space corresponding to the deformation state. More specifically, step 120, which maps the vertex of the yarn to the mesh of the extended garment pattern, includes a step of obtaining parameters corresponding to the deformation state of the material space corresponding to the garment pattern, a step of interpolating pre-calculated displacements based on the parameters corresponding to the deformation state sample to obtain the displacement of the vertex corresponding to the parameters, and a step of determining the position of the vertex in the material space corresponding to the deformation state based on the obtained displacement. The specific operation of step 120, which determines the position of the yarn in the material space corresponding to the deformation state, will be described in detail below.

[0049] According to one embodiment, step 120 of mapping the yarn vertices to the mesh of the extended garment pattern includes copying the yarn vertices mapped to areas where the first and second meshes overlap in the garment pattern, and mapping each of the copied vertices to the first and second meshes. For example, the first and second meshes may be included in a margin mesh. In other words, since the addition of a margin mesh can cause mesh overlap in the garment pattern, overlapping meshes constitute a margin mesh.

[0050] For example, referring to Figure 3a, a margin mesh may be added to the first region 311, which is the area outside the first boundary line 301 of the garment pattern, and a margin mesh may be added to the second region 312, which is the area outside the second boundary line 302. The first region 311 and the second region 312, to which the margin mesh is added, may partially overlap. Yarn vertices may be placed in the garment pattern. The yarn vertex 321 may be placed in the area where the first region 311 and the second region 312 overlap. The vertex 321 may be copied into two copies. When one of the copied vertex 321 is called the first vertex and the other is called the second vertex, the first vertex may be mapped to the mesh of the first region 311, and the second vertex may be mapped to the mesh of the second region 312. For example, referring to Figure 3b, which shows only the first region 311 of the garment pattern, the first vertex 322 is placed in the first region 311, and referring to Figure 3c, which shows only the second region 312 of the garment pattern, the second vertex 323 is placed in the second region 312. In the two-dimensional garment pattern, the first region 311 and the second region 312 overlap, but in the virtual garment, the first region 311 and the second region 312 do not overlap. The vertex 321 is copied, and each copied vertex 321 is mapped to the mesh of the first region 311 and the mesh of the second region 312, so that yarn can be simulated in all of the first region 311 and the second region 312 in the virtual garment.

[0051] Referring again to Figure 1, according to one embodiment, step 120 of mapping the vertices to the mesh of the extended garment pattern includes moving the vertices of yarn located outside the extended garment pattern onto the boundary line of the extended garment pattern. As an example, in knitwear, the yarn may have a periodically repeating shape. When placing the vertices of yarn with a periodically repeating shape into a garment pattern, some of the vertices may be located outside the garment pattern.

[0052] For example, referring to Figure 4a, if the yarn 401 has a periodically repeating shape, the first vertex 420, among the vertices at regular intervals on the centerline of the yarn 401, may be positioned outside the garment pattern 410. The first vertex 420 positioned outside the garment pattern 410 is moved along the boundary line of the garment pattern 410. For example, the position of the first vertex 420 may be changed at the intersection of the edge 430 connected to the first vertex 420 and the boundary line of the garment pattern. For example, referring to Figure 4b, the position of the first vertex may be changed at the intersection 440 of the edge connected to the first vertex and the boundary line of the garment pattern.

[0053] Referring again to Figure 1, according to one embodiment, step 120 of mapping the vertex to the mesh of the extended garment pattern includes the steps of rotating the yarn and mapping the vertex of the rotated yarn to the mesh of the extended garment pattern based on the orientation information of the knit structure corresponding to the knitwear. For example, the orientation information of the knit structure may be included in the physical property data of the knitwear. The orientation information of the knit structure is information that indicates the direction in which the yarn is placed on the garment or garment pattern, and may include, for example, a specific angle, a direction vector, or a rotation value. For example, the orientation information of the knit structure may include information that indicates the degree and / or direction of rotation of the yarn relative to the default state of the yarn. The yarn is rotated by the amount indicated by the orientation information of the knit structure in the default state and then placed on the garment pattern. For example, if the orientation information of the knit structure indicates horizontal or 0 degrees, the yarn may be placed on the garment pattern in the default state. For example, if the orientation information of the knit structure indicates vertical or 90 degrees, the yarn is rotated by 90 degrees in the default state and then placed on the garment pattern.

[0054] For example, referring to Figures 5a to 5c, garments with knitted structures whose shapes differ from each other may be rendered depending on the direction information of the knitted structure. For example, the knitted structure 510 of the garment exemplified in Figure 5a is the shape corresponding to the default state of the yarn or the direction information of the knitted structure 510 indicating 0 degrees. Referring to Figure 5b, if the direction information of the knitted structure 520 indicates a 45-degree rotation, the knitted structure 520 with the shape of the knitted structure 510 in Figure 5a rotated by 45 degrees will be rendered. Referring to Figure 5c, if the direction information of the knitted structure 530 indicates a 90-degree rotation, the knitted structure 530 with the shape of the knitted structure 510 in Figure 5a rotated by 90 degrees will be rendered.

[0055] A garment simulation method according to one embodiment includes step 130 of generating rendering information for knitwear by simulating a garment pattern on which yarn is placed based on a mapping relationship between vertices and the mesh of the garment pattern. The rendering information for knitwear may be generated through the simulation of a garment pattern on which yarn is placed. The rendering information for knitwear includes information for outputting the shape of a garment with a three-dimensional knit structure obtained by draping the garment pattern on which yarn is placed onto a three-dimensional object.

[0056] According to one embodiment, step 130 for generating rendering information of knitwear includes the steps of tessellating the centerlines of the yarn with a cylinder mesh, and generating rendering information of knitwear by simulating a garment pattern in which the tessellated yarn is placed based on the mapping relationship between the vertices and the mesh of the garment pattern. The centerlines of the yarn, which have no volume, are tessellated with a cylinder mesh that has volume. The centerlines of the yarn are tessellated with a cylinder mesh of a certain thickness. As an example, the thickness of the cylinder mesh may be determined based on the physical property data of the knitwear.

[0057] According to one embodiment, step 130 for generating rendering information for knitwear includes simulating yarn on a garment pattern in world-space corresponding to the deformation state. More specifically, the step of simulating yarn on a garment pattern in world-space corresponding to the deformation state includes obtaining the world-space position of the yarn vertex corresponding to the knitwear based on the material-space position of the yarn vertex corresponding to the deformation state, and generating rendering information for knitwear based on the obtained world-space position. World space corresponds to the space corresponding to a three-dimensional garment obtained by draping a two-dimensional garment pattern onto a three-dimensional object. Two-dimensional mesh information corresponding to the material-space of the garment pattern and three-dimensional mesh information corresponding to world space may be obtained through garment simulation. The specific operation of the step of simulating yarn on a garment pattern in world-space corresponding to the deformation state will be described in detail below.

[0058] Figure 6 illustrates a user interface screen for setting physical property data of knitwear according to one embodiment.

[0059] Referring to screen 600 in Figure 6, the setting values ​​for the knitwear's physical properties are entered via the user interface. As an example, the user may enter the setting values ​​for the knitwear's physical properties via the user interface provided on the terminal.

[0060] As an example, the physical property data of knitwear may include yarn thickness information. The yarn thickness value is set via the yarn thickness input window 610 of the user interface. Knitwear containing yarn with the set yarn thickness value can be simulated.

[0061] As an example, the physical property data for knitwear may include setting information on whether or not to add margin mesh (e.g., generate seams). The setting for whether or not to add margin mesh is made via the margin mesh setting window 620. If it is set to add margin mesh, then, as described above, margin mesh may be added to the garment pattern.

[0062] As an example, the physical property data of knitwear may include size information (e.g., seam length) of the area to which margin mesh is added (e.g., seam allowance area). The size of the area to which margin mesh is added is set via the input window 630. The size of the area to which margin mesh is added in a garment pattern may be determined by the size entered via the input window 630.

[0063] As an example, the physical property data of knitwear may include margin mesh curvature information (e.g., seam curvature). The margin mesh curvature is set via the margin mesh curvature input window 640. The curvature of the margin mesh added to the garment pattern may be determined by the value entered via the input window 640.

[0064] As an example, the physical property data of knitwear may include information about the orientation of the knit structure (e.g., knit direction). The orientation of the knit structure is determined via the knit structure direction input window 650. The knitwear can be simulated in the direction of the knit structure entered via the input window 650.

[0065] In addition, the physical property data of the knitwear may include information that indicates the characteristics of the knitwear. For example, the physical property data of the knitwear may include knit structure type information (e.g., stitching type), density information (e.g., gauge), and color information (e.g., ply color). The interface includes a knit structure type setting window 660, a density input window 670, and a color input window 680.

[0066] Figures 7a to 12 illustrate a knitting simulation method for a yarn base according to one embodiment.

[0067] A knitting simulation method for a yarn base according to one embodiment will be abbreviated as such in the following reference to the knitting simulation method. The knitting simulation method for a yarn base corresponds to steps 120 to 130 described above. More specifically, it corresponds to the step of determining the position of the yarn in the material space corresponding to the deformation state described above, and the step of simulating the yarn in a garment pattern in the world space corresponding to the deformation state.

[0068] One embodiment of the knitted fabric simulation method may include a method for animating (or simulating) the geometric structure of a yarn-level fabric (or knitted fabric) on a deformed underlying mesh using a mechanism-aware fashion approach. One embodiment of the knitted fabric simulation method is a method for reproducing developments such as the tightening effect of knit loops during stretching by interpolating the yarn geometric structure, which has been calculated in advance using a triangle strain. For example, referring to Figure 7a, the geometric structure of the yarn in a knitted fabric before deformation is illustrated. When the knitted fabric is stretched, the simulation result of a knitted fabric that does not consider yarn-level deformation is shown in Figure 7b. Referring to Figure 7b, the knitted fabric may be simulated so that the stretching of the yarn occurs uniformly when the knitted fabric is stretched, regardless of the geometric structure of the yarn. On the other hand, when the knitted fabric is stretched, the simulation result of a knitted fabric that considers yarn-level deformation is shown in Figure 7c. In other words, the simulation result in Figure 7c is the simulation result of a knitted fabric generated by the knitted fabric simulation method according to one embodiment. Referring to Figure 7c, the simulation shows that if the knitted fabric is stretched considering the geometric structure of the yarn, the yarn loops will tighten.

[0069] One embodiment of the knitted fabric simulation method is a simulation method that adds yarn-level deformation to a mesh-based fabric simulation. The periodic movement (behavior) of the yarn pattern may be pre-calculated based on large-scale deformation of the underlying fabric. The yarn pattern refers to the garment pattern in which the yarns are arranged. By interpolating the deformed yarn pattern at runtime based on the deformation state of the fabric mesh, the yarn-level geometric structure rearranged by the yarn-level mechanism can be generated in real time.

[0070] One embodiment of the knitting simulation method can accept an undeformed yarn pattern and large-scale surface deformation as input for simulating the deformed geometric structure of the yarn pattern. The large-scale surface deformation corresponds to data encoded via a first fundamental form I and a second fundamental form II. As will be explained in detail below, the large-scale surface deformation is used to define boundary conditions and to optimize the structure of the elastostatic equilibrium of the yarn pattern.

[0071] JPEG2026524588000002.jpg47168

[0072] During optimization, the kinematics of the position of the yarn vertex can be expressed by the following equations 1 and 2.

[0073]

number

number

[0074] JPEG2026524588000005.jpg58168

[0075] JPEG2026524588000006.jpg35168

[0076]

number

[0077] To calculate the rotation matrix R, the derivative of the normal vector ∇n is calculated as shown in equation 4 below.

[0078]

number

[0079] As shown in equation 5, a, b, and r are calculated.

[0080]

number

[0081] As shown in equation 6, R(X1, X2) is calculated.

[0082]

number

[0083] JPEG2026524588000011.jpg19167

[0084] JPEG2026524588000012.jpg57167

[0085] JPEG2026524588000013.jpg51167

[0086] An optimization process according to one embodiment may include a null space in which the Jahn curve can slide. In other words, the elastic energy E of a periodic Jahn curve x(s) represented by parameter s remains unchanged even if it slides by a parametric shift Δs. In other words, E(x(s)) = E(x(s+Δs)). Geometrically, the sliding motion corresponds to the Jahn curve sliding tangentially while maintaining the same periodic form. In the optimizer, all sliding states are considered identical, and the actual result may be arbitrarily determined by the internal parameters of the numeric solver. By definition, the null space does not affect the homogenized energy. Completely different forms of the Jahn curve may be generated by interpolating between two sliding states.

[0087] For example, if the two curves 910 and 930 shown in Figures 9a and 9c are yarns of the same form, shifting the starting position of curve 910 in Figure 9a by a certain distance results in curve 930 in Figure 9c. Interpolating curves 910 in Figure 9a and 930 in Figure 9c generates a new curve 920 that is different from curves 910 in Figure 9a and 930 in Figure 9c, as shown in Figure 9b. This is a development where, even though the two curves 910 and 930 shown in Figures 9a and 9c are mathematically the same form, the representation (or parametric representation) is different, and distortion occurs during interpolation.

[0088] The zero space can induce disruptive interpolation artifacts even for nearly identical deformation states. By adding constraints to the optimization process, parameterized yarn sliding is eliminated, and the zero space is effectively removed. More specifically, the constraint fixes one vertex for each periodic yarn on the garment pattern boundary, as shown in Equation 7.

[0089]

number

[0090] In equation 7, N is the undeformed normal vector to the garment pattern boundary, where N = (1, 0) T Alternatively, N=(0, 1) T This is one of them. A sparse set of vertex constraints can efficiently and effectively remove interpolation artifacts. For large deformations described in the first and second basic shapes (I and II) through the constraints, a physically realistic yarn form can be obtained.

[0091] For example, when interpolating the geometric structure of yarn, if the tangential sliding of the yarn is not considered, unrealistic distortions of the yarn can occur in the knitted fabric, as shown in Figure 9d. For instance, distortions such as self-collision or floating loops can occur. On the other hand, by introducing a sliding constraint, natural and physically reasonable interpolation results can be obtained, as shown in Figure 9e.

[0092] The geometric structure of the yarn corresponding to a typical deformation state sample is pre-calculated, and at runtime, the geometric structure of the yarn corresponding to the pre-calculated deformation state sample is interpolated to obtain the geometric structure of the yarn corresponding to the actual deformation state. Since I and II are each 2x2 symmetric tensors, directly parameterizing the deformation into I and II results in a 6-dimensional function, which incurs significant costs for pre-calculation, storage, and retrieval at runtime. Here, the dimensionality of the deformation can be reduced as much as possible by parameterizing the deformation with variables.

[0093] The first basic shape I is reparameterized using a three-dimensional function as shown in Equation 8, based on in-plane strains.

[0094]

number

[0095] II could be parameterized similarly to Equation 4 by introducing additional curvature variables to increase the dimensionality of the dataset, but below we show that bending deformation can be reasonably approximated by stretching variables alone. The entire large-scale deformation space is given by three variables s x , s a , s ySampling can be done using only this method, significantly reducing memory and computational overhead. Deformation state samples may also be sampled on a regular 3D grid.

[0096] At runtime, the interpolated yarn geometry can be mapped to a deformed mesh (e.g., a triangle mesh). The deformation of the mapped mesh is naturally inherited by the yarn geometry. In a precomputation step, this may be stored as displacement in material space corresponding to the deformation state sample.

[0097] JPEG2026524588000016.jpg27167

[0098] JPEG2026524588000017.jpg29167

[0099] JPEG2026524588000018.jpg774

[0100]

number

[0101] In equation 9, Φ is the deformed midsurface, and n is the normal vector of the midsurface.

[0102] A gradient is defined as shown in equation 10.

[0103]

number

[0104] By definition, ∇Φ is shown as in equation 11.

[0105]

number

[0106] JPEG2026524588000022.jpg13167

[0107] [Number]

[0108] JPEG2026524588000024.jpg34167

[0109] [Number]

[0110] JPEG2026524588000026.jpg21167

[0111] [Number]

[0112] In the rest pose, I = Id, II = 0, and ΔQ = 0.

[0113] For each vertex i of each yarn pattern, and for various in-plane deformation state samples j: ΔQi(s xj , s aj , s yj ), a database of the displacement ΔQ of the yarn in the material space can be constructed. The database of ΔQ corresponds to a grid of example deformations. Alternatively, the database of ΔQ corresponds to a 3D displacement texture for each vertex of each yarn. When interpolation is performed on the displacements of the deformation state samples, for a given in-plane deformation s xj , s aj , s yjA yarn-level displacement map is obtained for each of these deformations. For deformations directly sampled in the ΔQ database, the accurate yarn pattern is reconstructed, while for intermediate deformations among the sampled deformations, an approximate pattern is generated.

[0114] A database of yarn pattern displacements for various deformation states is applied to a yarn pattern tiled on a triangular mesh during animation.

[0115] JPEG2026524588000028.jpg34168

[0116] As an example, algorithm 1 illustrated in Figure 11 includes a process of rendering q in response to inputs including mesh animation, yarn pattern, and displacement ΔQ.

[0117] An initial, undeformed yarn mesh is generated corresponding to an undeformed mesh (e.g., a triangular mesh) that has been pre-calculated. A 2D background grid is generated on the mesh's UV coordinate system, where the cell size is the same as the size of the periodic pattern. For example, the geometric structure of the yarn is copied to all cells that overlap with the undeformed mesh. For example, yarn vertices that do not exist within the mesh are removed. For example, yarn fragments shorter than the user-specified length may be removed for aesthetic purposes. The barycentric coordinate system of the material space for each yarn vertex is pre-calculated.

[0118] For each animation frame, discrete fundamental forms I and II for each mesh are calculated as shown in equation 15 below.

[0119]

number

[0120] In Equation 15, F is the deformation gradient of the mesh, and Λ is the triangle-averaged shape operator. I and II may be distributed to the vertices of the triangular mesh using modified Shepard weights. Finally, the I and II values ​​of the vertices of the triangular mesh where the yarn vertices are located are interpolated to estimate the actual deformation state of the yarn vertices.

[0121] According to one embodiment, the effect of bending behavior is approximated by adding stretching and compression through surface curvature.

[0122] The full domain of a thin shell x represented by an intermediate surface Φ having a normal vector n is given by equation 16 below.

[0123]

number

[0124] In equation 16, h ∈ [-H / 2, H / 2] is the normal coordinate with respect to the shell thickness H. Here, the Cauchy-Green deformation tensor can be expressed as shown in equation 17 below.

[0125]

number

[0126] Equation 17 can be interpreted as the first fundamental shape I(h) which is secondarily dependent on h. The quadratic term in Equation 17 can generally be ignored. Also, the fundamental shape of Φ is ∇Φ T ∇Φ=I, and similarly ∇ΦT ∇n=∇n T ∇Φ = -II. As a result, the linearized expression is as shown in Equation 18.

[0127]

number

[0128] Then, the data ΔQ is calculated in advance for the in-plane deformation s. s Using (s), the linearized bending model can be expressed as shown in Equation 19 below.

[0129]

number

[0130] In other words, as explained through equation 18, the first basic shape I can be improved as a form that changes along the surface normal direction, as shown in equation 20 below.

[0131]

number

[0132] As an example, referring to Figure 12, the extruded volume 1220 around the bent intermediate surface 1210 by the bending model may be approximated by a volume 1230 in which the upper part of the intermediate surface 1210 is stretched and the lower part is compressed and linearized.

[0133] Like many elastic materials, when fabric is compressed, it may buckle (or deform) outside the plane. To prevent abnormal yarn deformation (buckling) due to compression, the eigenvalue λ of the first basic shape I is clamped at a lower limit before querying the yarn displacement. This allows buckling to be reduced using a user-adjustable method.

[0134] As an example, the minimum value λ for an eigenvalue of I(Z) min (For example, 0.8) may be set. An eigenvalue λ < 1 signifies a compressed state. As I converges to the identity matrix (Id), ΔQ converges to 0, so the clamping method can reduce only local changes while preserving the overall large-scale deformation caused by the triangular mesh.

[0135] After clamping I, the deformation rate s is given by equation 8. x , s a , s z It is converted to the displacement ΔQ(s) of Yarn. x , s a , s z This may be done using trilinear interpolation. The coordinates of the yarn in the deformed material space are calculated as shown in equation 21 below.

[0136]

number

[0137] The deformation rate exceeding the sampled range is ΔQ(s x , s a , s z Clamping is performed to the nearest neighbor from the dataset. Similar to compression clamping, constant extrapolation can still inherit large-scale deformations from the mesh embedding while limiting local deformations.

[0138] Equation 22 can be used to map the yarn vertex to world space x.

[0139]

number

[0140] Equation 22 involves extruding the mesh surface Φ in world space along the normal vector n. To avoid linear embedding artifacts per fragment, Phong deformation and interpolated vertex normal vectors can be used to generate Φ and shell volumes more smoothly.

[0141] JPEG2026524588000037.jpg18167

[0142] The deformation calculation of yarn vertices and their mapping in world space can be trivially parallelized and therefore implemented in a GPU compute shader. ΔQ interpolation may be performed using a single 3D texture interpolation operation per yarn vertex.

[0143] The deformed yarn may be tessellated with a cylinder mesh in the geometry shader. Ply and fiber-level details may be approximated using twistable normal maps and ambient occlusion maps in sequence. Volume conservation can be approximated by locally readjusting the yarn radius during stretching.

[0144] Figure 13 is an illustrative diagram of the configuration of an electronic device according to one embodiment.

[0145] Referring to Figure 13, the electronic device 1300 according to one embodiment includes a processor 1301, a memory 1303, and an input / output device (I / O) 1305. The electronic device 1300 according to one embodiment includes an apparatus for performing the garment simulation method for knitwear described above, referring to Figures 1 to 12. For example, the electronic device 1300 may include at least one of a server and a user terminal (e.g., a personal PC, mobile phone, tablet, wearable device, etc.).

[0146] A processor 1301 according to one embodiment may include at least one processor, which includes processing circuitry.

[0147] A processor 1301 according to one embodiment can perform at least one of the operations included in the garment simulation method for knitwear described above with reference to Figures 1 to 12. For example, the processor 1301 can perform at least one of the following operations: adding a margin mesh to a garment pattern corresponding to knitwear to extend the garment pattern; mapping the vertices of yarn corresponding to knitwear to the mesh of the extended garment pattern; and generating rendering information for knitwear by simulating the garment pattern on which the yarn is placed based on the mapping relationship between the vertices and the mesh of the garment pattern.

[0148] In one embodiment, the memory 1303 may be a volatile memory or a non-volatile memory, and can store data related to the garment simulation method for knitwear described above with reference to Figures 1 to 12. For example, the memory 1003 may store data generated during the execution process of the garment simulation method for knitwear described above with reference to Figures 1 to 12, or data necessary to perform the garment simulation method for knitwear described above with reference to Figures 1 to 12.

[0149] According to one embodiment, the memory 1303 may not be part of the electronic device 1300, but may be included in an external device accessible by the electronic device 1300. In this case, the electronic device 1300 can receive data stored in the memory 1303 included in the external device via a communication device and transmit data stored in the memory 1303.

[0150] According to one embodiment, the memory 1303 can store a program that embodies the garment simulation method for knitwear described above, with reference to Figures 1 to 12. The processor 1301 can execute the program stored in the memory 1303 and control the electronic device 1300. The code of the program executed by the processor 1301 may be stored in the memory 1303.

[0151] For example, memory 1303 may store instructions. When instructions stored in memory 1303 are executed individually or collectively by processor 1301, the electronic device 1300 will perform the following actions: adding a margin mesh to the garment pattern corresponding to the knitwear and extending the garment pattern; mapping the vertices of the yarn corresponding to the knitwear to the mesh of the extended garment pattern; and simulating the garment pattern with the yarn arranged based on the mapping relationship between the vertices and the garment pattern mesh to generate rendering information for the knitwear.

[0152] An input / output device 1305 according to one embodiment may include an input device and an output device. For example, user input relating to the physical properties of knitwear may be received via the input / output device 1305. For example, rendering information of knitwear may be output via the input / output device 1305.

[0153] An electronic device 1300 according to one embodiment may further include other components not shown. For example, the electronic device 1300 may further include a communication device for communication with other devices (e.g., a server, terminal, network, etc.). Also, for example, the electronic device 1300 may further include other components such as a transceiver, various sensors, a database, etc.

[0154] The embodiments described above can be embodied in hardware components, software components, and / or combinations of hardware and software components. For example, the adaptive supersampling apparatus, method, and components described in the embodiments can be embodied using a general-purpose computer or a special-purpose computer, such as a processor, controller, ALU (arithmetic logic unit), digital signal processor, microcomputer, FPGA (Field Programmable Gate Array), PLU (Programmable Logic Unit), microprocessor, or other device capable of executing and responding to commands. The processing apparatus can execute an operating system (OS) and software applications that run on the OS. The processing apparatus may also access, store, manipulate, process, and generate data in response to the execution of the software. For convenience of understanding, it has sometimes been described that one processing apparatus is used, but a person with ordinary skill in the art will see that the processing apparatus may include multiple processing elements and / or multiple types of processing elements. For example, a processing adaptive supersampling apparatus may include multiple processors or one processor and one controller. Furthermore, other processing configurations, such as parallel processors, are also possible.

[0155] Software may include computer programs, code, instructions, or any combination thereof, which can configure or instruct a processing unit independently or collectively as desired. Software and / or data may be interpreted by a processing adaptive supersampling device or permanently embodied in any type of machine, component, physical adaptive supersampling device, virtual adaptive supersampling device, computer storage medium, or adaptive supersampling device, or transmitted signal waves, for the purpose of providing instructions or data to a processing adaptive supersampling device. Software may be distributed across a networked computer system and stored or executed in a distributed manner. Software and data may be stored on computer-readable recording media.

[0156] The method according to this embodiment is embodied in the form of program instructions that are implemented via various computer means and recorded on a computer-readable recording medium. The recording medium includes program instructions, data files, data structures, etc., individually or in combination. The recording medium and program instructions may be specifically designed and configured for the purposes of the present invention, or they may be known and usable by those skilled in the art who have technology in the field of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tapes, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floppy disks, and hardware devices specifically configured to store and execute program instructions, such as ROMs, RAMs, and flash memory. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code executed by a computer using an interpreter or the like.

[0157] The hardware device described above may be configured to operate as one or more software models to perform the operations shown in the present invention, and vice versa.

[0158] As described above, although embodiments have been illustrated with limited drawings, a person with ordinary skill in the art can apply various technical modifications and variations based on the above description. For example, the described technique may be performed in a different order than described, and / or the described system, structure, apparatus, circuit, and other components may be combined or assembled in a different manner than described, or replaced or substituted by other components or equivalents, and still achieve the desired results.

[0159] Therefore, other embodiments, other embodiments, and claims equivalent to those described below also fall within the scope of the claims.

Claims

1. A method for simulating knitwear, The steps include adding a margin mesh to the garment pattern corresponding to the knitwear and extending the garment pattern, The steps include mapping the vertex of the yarn corresponding to the knitwear to the mesh of the extended garment pattern, The steps include generating rendering information for the knitwear by simulating the garment pattern on which the yarn is arranged based on the mapping relationship between the vertex and the mesh of the garment pattern, Methods that include...

2. The step of mapping the vertex to the mesh of the extended garment pattern is: The steps include obtaining parameters corresponding to the deformation state of the material space corresponding to the garment pattern, The steps include: interpolating the displacement calculated in advance based on parameters corresponding to the deformation state sample, and obtaining the displacement of the vertex corresponding to the parameters; A step of determining the position of the vertex in the material space corresponding to the deformation state based on the acquired displacement, The method according to claim 1, including the method described in claim 1.

3. The step of generating rendering information for the knitwear is: The steps include obtaining the position of the vertex in the world space corresponding to the knitwear based on the position of the vertex in the material space corresponding to the deformation state, The steps include generating rendering information for the knitwear based on the acquired world space position, The method according to claim 2, including the method described in claim 2.

4. The method according to claim 1, wherein the margin mesh is added to the area outside the boundary of the garment pattern with a certain width.

5. The method according to claim 1, wherein the step of extending the garment pattern includes adding the margin mesh, which has a curvature of a certain size, to the garment pattern corresponding to the knitwear.

6. The step of extending the garment pattern includes the step of adding the margin mesh to the garment pattern based on the physical property data of the knitwear, The method according to claim 1, wherein the physical property data of the knitwear includes at least one of setting information on whether or not the margin mesh is added, size information of the region where the margin mesh is generated, and curvature information of the margin mesh.

7. The method according to claim 1, wherein the vertex includes at least one vertex located on the centerline of the yarn.

8. The step of generating rendering information for the knitwear is: The steps include tessellating the center line of the yarn with a cylinder mesh, The steps include generating rendering information for the knitwear by simulating the garment pattern on which the tessellated yarn is arranged based on the mapping relationship between the vertex and the mesh of the garment pattern, The method according to claim 1, including the method described in claim 1.

9. The method according to claim 1, wherein the step of mapping the vertex to the mesh of the extended garment pattern includes the steps of copying the vertex of the yarn mapped to the region where the first mesh and the second mesh overlap in the garment pattern, and mapping each of the copied vertex to the first mesh and the second mesh.

10. The method according to claim 9, wherein the first mesh and the second mesh are included in the margin mesh.

11. The method according to claim 1, wherein the step of mapping the vertex to the mesh of the extended garment pattern includes moving the vertex of the yarn located outside the extended garment pattern onto the boundary line of the extended garment pattern.

12. The step of mapping the vertex to the mesh of the extended garment pattern is: The steps include rotating the yarn based on the directional information of the knit structure corresponding to the knitwear, The steps include mapping the vertex of the rotated yarn to the mesh of the extended garment pattern, The method according to claim 1, including the method described in claim 1.

13. A computer program stored on a computer-readable medium for use in conjunction with hardware to perform the method of claim 1.

14. An electronic device, A processor including a processing circuit, Memory for storing instructions, Includes, When the instruction is executed individually or collectively by the at least one processor, the electronic device, The process involves adding a margin mesh to a garment pattern corresponding to knitwear and extending the garment pattern, The operation of mapping the vertex of the yarn corresponding to the knitwear to the mesh of the extended garment pattern, The operation of generating rendering information for the knitwear by simulating the garment pattern on which the yarn is arranged based on the mapping relationship between the vertex and the mesh of the garment pattern, An electronic device in which this is performed.

15. The operation of mapping the vertex to the mesh of the extended garment pattern is: An operation to acquire parameters corresponding to the deformation state of the material space corresponding to the garment pattern, An operation to interpolate the displacement calculated in advance based on the parameters corresponding to the deformation state sample, and to obtain the displacement of the vertex corresponding to the parameters, Based on the acquired displacement, the operation of determining the position of the vertex in the material space corresponding to the deformation state, The electronic device according to claim 14, including the electronic device according to claim 14.

16. The operation to generate rendering information for the aforementioned knitwear is: An operation to obtain the position of the vertex in world space corresponding to the knitwear based on the position of the vertex in material space corresponding to the deformation state, Based on the acquired world space position, the operation of generating rendering information for the knitwear, The electronic device according to claim 15, including the electronic device according to claim 15.

17. The electronic device according to claim 14, wherein the operation to extend the garment pattern includes the operation to add the margin mesh, which has a curvature of a certain size, to the garment pattern corresponding to the knitwear.

18. The operation to extend the garment pattern includes the operation to add the margin mesh to the garment pattern based on the physical property data of the knitwear. The electronic device according to claim 14, wherein the physical property data of the knitwear includes at least one of setting information on whether or not the margin mesh is added, size information of the region where the margin mesh is generated, and curvature information of the margin mesh.

19. The operation to generate rendering information for the aforementioned knitwear is: The operation of tessellating the center line of the yarn with a cylinder mesh, Based on the mapping relationship between the vertex and the mesh of the garment pattern, the operation generates rendering information of the knitwear by simulating the garment pattern on which the tessellated yarn is arranged, The electronic device according to claim 14, including the electronic device according to claim 14.

20. The electronic device according to claim 14, wherein the operation of mapping the vertex to the mesh of the extended garment pattern includes copying the vertex of the yarn mapped to the region where the first mesh and the second mesh overlap in the garment pattern, and mapping each of the copied vertex to the first mesh and the second mesh.

Images