Improved simulation of knitted garments using twist rate parameters

Abstract

A garment simulation method and apparatus are disclosed. A garment simulation method relating to knitwear according to one embodiment includes the steps of determining the texture of yarn corresponding to multiple plies of different colors based on the twist speed parameter of yarn corresponding to knitwear, and generating rendering information of knitwear by simulating a garment pattern corresponding to knitwear on which the yarn of the determined texture is arranged.

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: determining the texture of a yarn corresponding to a plurality of plies of different colors based on the twist speed parameter of the yarn corresponding to the knitwear; and generating rendering information of the knitwear by simulating a garment pattern corresponding to the knitwear on which the yarn of the determined texture is arranged.

[0004] Based on the aforementioned twist velocity parameter, the number of times a particular ply is shown in a given section of the yarn can be determined.

[0005] The aforementioned twist speed parameter can be determined based on user input.

[0006] The step of determining the texture of the yarn may include determining the texture of the yarn based on the twist velocity parameter and the arc parameter of the yarn.

[0007] The arc parameter may include a random parameter that indicates the starting position of the yarn twist.

[0008] The arc parameters of the different yarns arranged in the garment pattern can be determined to be different values ​​from each other.

[0009] The garment simulation method for the knitwear may further include the step of mapping vertices on the centerline of the yarn to the mesh of the garment pattern.

[0010] The step of determining the texture of the yarn may include the steps of tessellating the center line of the yarn with a cylinder mesh; and determining the texture of the tessellated yarn corresponding to a plurality of plies of different colors based on the twist rate parameter.

[0011] The step of generating rendering information for the knitwear may 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.

[0012] The step of mapping the vertex to the mesh of the 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.

[0013] 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.

[0014] An electronic device according to one embodiment includes at least one processor including processing circuitry; and a memory for storing instructions, wherein, when the instructions are executed individually or collectively by the at least one processor, the electronic device performs the operation of determining the texture of a yarn corresponding to a plurality of plies of different colors based on the twist rate parameter of the yarn corresponding to the knitwear; and the operation of generating rendering information of the knitwear by simulating a garment pattern corresponding to the knitwear on which the yarn of the determined texture is arranged.

[0015] Based on the aforementioned twist velocity parameter, the number of times a particular ply is shown in a given section of the yarn can be determined.

[0016] The operation to determine the texture of the yarn may include an operation to determine the texture of the yarn based on the twist velocity parameter and the arc parameter of the yarn.

[0017] The arc parameters can include a random parameter that indicates the twist start position of the yarn.

[0018] The arc parameters of different yarns arranged in the clothing pattern can be determined to have different values.

[0019] When the instructions are executed alone or jointly by the at least one processor, the electronic device can further perform an operation of mapping a vertex on the centerline of the yarn to the mesh of the clothing pattern.

[0020] The operation of determining the texture of the yarn can include an operation of tessellating the centerline of the yarn with a cylinder mesh; and an operation of determining the texture of the tessellated yarn corresponding to a plurality of plies of different colors based on the twist speed parameter.

[0021] The operation of generating the rendering information of the knitted wear can include an operation of simulating the clothing pattern in which the yarn is arranged based on the mapping relationship between the vertex and the mesh of the clothing pattern, thereby generating the rendering information of the knitted wear.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 1 is a flowchart of an operation of a clothing simulation method for knitted wear according to an embodiment. [Figure 2a] FIG. 2a is a diagram illustrating cross-sections of a certain section of yarns set such that the twist speed parameters are different from each other. [Figure 2b] FIG. 2b is a diagram illustrating cross-sections of a certain section of yarns set such that the twist speed parameters are different from each other. [Figure 3] Figure 3 is a diagram illustrating the specific operation of a clothing simulation method 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]

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] Figure 1 is an operation flowchart of a garment simulation method for knitwear according to one embodiment.

[0032] 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.

[0033] A garment simulation method relating to knitwear according to one embodiment will be referred to simply as "the method" or "garment simulation method" below.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] A garment simulation method according to one embodiment includes step 110 of determining the texture of yarn corresponding to multiple plies of different colors based on the twist speed parameter of the yarn corresponding to knitwear.

[0038] A yarn contains one or more plies. For example, a yarn may be produced by twisting (or twisting) one or more plies. The number of plies contained in a yarn can change its physical properties (e.g., density, feel, durability, flexibility, etc.). If a yarn contains multiple plies, the colors of the multiple plies may be different or the same.

[0039] The texture of the yarn may include, for example, at least one of the color distribution of the yarn and the visual pattern of the yarn, as visual characteristics of the yarn surface. The texture of the yarn can be determined based on the twist rate parameter of the yarn.

[0040] The twist rate (or twist ratio) parameter corresponds to a parameter that indicates the number of ply twists per unit length of yarn. A larger value for the twist rate parameter results in a larger number of ply twists per unit length of yarn. Based on the twist rate parameter, the number of times a particular ply is shown in a given section of yarn can be determined. For example, Figures 2a and 2b illustrate cross-sections of yarn in given sections where the twist rate parameters are set to be different. The twist rate parameter in Figure 2a has a larger value than the twist rate parameter in Figure 2b. Referring to Figures 2a and 2b, the number of ply twists shown in given sections of yarn may differ. For example, a given section of yarn shown in Figure 2a may show 8 ply twists, while a given section of yarn shown in Figure 2b may show 5 ply twists. Referring to Figures 2a and 2b, a larger twist rate parameter results in an even greater number of ply twists in given sections of yarn.

[0041] For example, if a yarn contains both a first-color ply and a second-color ply, a larger twist speed parameter increases the probability that both the first-color and second-color ply are present in a given section of the yarn. A smaller twist speed parameter increases the probability that sections of the yarn will either lack the first-color ply or lack the second-color ply. The color distribution of the yarn ply is controlled by the setting of the twist speed parameter. For example, since the rotation interval of ply of different colors within the yarn is determined by the value of the twist speed parameter, a melange texture for knitwear may be achieved by setting the twist speed parameter. Alternatively, a marled texture for knitwear may be achieved by setting the twist speed parameter.

[0042] According to one embodiment, the twist rate parameter can be determined based on the physical properties data of the knitwear. The physical properties data of the knitwear is information indicating the physical properties of the knitwear, and may include, for example, at least one of the following: information on the stitching type of the knitwear, information on the density (gauge) of the knitwear, information on the direction of the knit structure, information on the thickness of the yarn, information on the number of plies contained in the yarn, information on the color of each ply contained in the yarn, and information for setting the randomization of the ply color distribution of the yarn. The information for setting the randomization of the ply color distribution of the yarn may include information for determining the twist rate parameter of the yarn. The physical properties data of the knitwear will be described in detail below.

[0043] According to one embodiment, the twist speed parameter can be determined based on user input. By adjusting the value of the twist speed parameter, the user can change the texture of the knitwear with which the yarn is placed, relating to the color distribution.

[0044] According to one embodiment, the method includes a step 110 for determining the texture of the yarn, a step for determining the texture of the yarn based on a twist velocity parameter and an arc (arc) parameter of the yarn.

[0045] The yarn arc parameter is a parameter that indicates the position on a curve defined along the yarn's centerline, and may be determined as a real value within a specific range that indicates the relative position from the yarn's start point to its end point, for example.

[0046] The arc parameter includes a random parameter that indicates the starting position of the yarn. The twist of the ply begins from the position of the yarn's centerline indicated by the arc parameter. The value of the arc parameter may be determined to be a random value. The arc parameters of different yarns placed in a garment pattern may be determined to be different values ​​from each other. In other words, since the value of the arc parameter of each yarn is determined to be a random value, and the value of the arc parameter of each yarn placed in a garment pattern corresponding to knitwear is a random value, the values ​​of the arc parameters of different yarns may be different or the same.

[0047] Depending on the random setting of the arc parameter values ​​for each yarn, noise (or irregularity) in the color distribution of different colored plies in the knit structure may occur. Depending on the random setting of the arc parameter values ​​for each yarn placed in the garment pattern, a melange texture can be realized in knitwear.

[0048] A garment simulation method according to one embodiment includes step 120 of generating rendering information for knitwear by simulating a garment pattern corresponding to knitwear on which yarn of a determined texture is placed. 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 may include information for outputting the shape of a garment made of a three-dimensional knit structure, which is made by attaching the garment pattern on which yarn is placed to a three-dimensional object.

[0049] Figure 3 is a diagram illustrating the specific operation of a clothing simulation method according to one embodiment.

[0050] Referring to Figure 3, a garment simulation method according to one embodiment includes step 310 of mapping yarn vertices to a garment pattern mesh. Yarn vertices may include at least one vertex located on the yarn's centerline. For example, the yarn may be modeled with edges connecting adjacent vertices located at regular intervals on the yarn's centerline. For example, it may be modeled with discrete elastic rods. Yarn modeling will be described in detail below.

[0051] Mapping yarn vertices to the garment pattern mesh means determining the position of each yarn vertex that makes up the knitwear on the garment pattern. Mapping yarn vertices to the 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.

[0052] According to one embodiment, step 310 of mapping the yarn vertex to the mesh of the garment pattern includes a step of determining the position of the yarn in material space corresponding to the deformation state. More specifically, step 310 of mapping the yarn vertex to the mesh of the garment pattern includes a step of obtaining parameters corresponding to the deformation state in 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 parameter, and a step of determining the position of the vertex in material space corresponding to the deformation state based on the obtained displacement. The specific operation of the step of determining the position of the yarn in material space corresponding to the deformation state will be described in detail below.

[0053] According to one embodiment, step 310 of mapping yarn vertices to the mesh of a garment pattern includes moving yarn vertices located outside the garment pattern onto the boundary of the garment pattern. As an example, in knitwear, the yarn may have a periodically repeating shape. When placing yarn vertices with a periodically repeating shape into a garment pattern, some vertices may be located outside the garment pattern.

[0054] 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.

[0055] Referring again to Figure 3, according to one embodiment, step 310 of mapping the yarn vertex to the mesh of the garment pattern includes the steps of rotating the yarn and mapping the rotated yarn vertex to the mesh of the 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.

[0056] 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.

[0057] Referring again to Figure 3, step 320 for determining the yarn texture corresponds to step 110 in Figure 1. Step 320 for determining the yarn texture includes determining the yarn texture based on ply data 321 and randomization setting data 322 for the ply color distribution. Ply data 321 includes physical property data of one or more plies contained in the yarn. For example, ply data 321 may include information on the number of plies contained in the yarn and color information for each ply contained in the yarn. For example, ply data 321 may include a ply normal map. The ply normal map corresponds to a texture map for simulating the surface bending and / or unevenness of the yarn corresponding to the twisting of the plies. The ply normal map may also be data for realistically simulating the surface texture of the yarn generated by the twisting of the plies. Randomization setting data 322 for randomizing the ply color distribution of the yarn is data for randomizing the ply color distribution of the yarn and may include, for example, at least one of the twist velocity parameter and the yarn arc parameter described above. As described above, the texture of the yarn can be determined based on at least one of the twist velocity parameter and the yarn arc parameter.

[0058] According to one embodiment, step 320 for determining the yarn texture includes the steps of tessellating the yarn centerline with a cylinder mesh and determining the texture of the tessellated yarn corresponding to multiple plies of different colors based on a twist rate parameter. The yarn centerline, which has no volume, may be tessellated with a volumetric cylinder mesh. The yarn centerline can be tessellated with a cylinder mesh of a certain thickness. For example, the thickness of the cylinder mesh may be determined based on the physical property data of the knitwear. The yarn texture determined in step 110 corresponds to the texture of the yarn tessellated with a cylinder mesh. In other words, the step of tessellating the yarn centerline with a cylinder mesh may be performed after step 310, which maps the yarn vertex to the mesh of the garment pattern.

[0059] Step 330, which generates rendering information for knitwear, corresponds to step 120 in Figure 1. According to one embodiment, step 330, which generates rendering information for knitwear, includes the step of generating rendering information for knitwear by simulating a garment pattern in which yarn is arranged based on the mapping relationship between vertices and the mesh of the garment pattern.

[0060] According to one embodiment, step 330 for generating rendering information of 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 of 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 by 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.

[0061] Figure 6 illustrates a user interface screen for setting physical property data of knitwear according to one embodiment.

[0062] 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.

[0063] As an example, the physical property data of knitwear may include yarn thickness information. The yarn thickness value may be set via the yarn thickness input window 610 of the user interface. Knitwear containing yarn with the set yarn thickness value can then be simulated.

[0064] As an example, the physical property data for knitwear may include ply color distribution randomization setting information (e.g., ply randomization (Melange)). Whether or not ply color distribution is randomized is set via the ply color distribution randomization setting window 620. If ply color distribution is set to be randomized, input of parameter values ​​for ply color distribution randomization is activated.

[0065] For example, if the ply color distribution is set to be randomized, the randomization factor input window 630 for determining the twist velocity parameter may be activated. The value of the randomization factor is input through the activated randomization factor input window 630. The value of the randomization factor corresponds to the twist velocity parameter. For example, a larger value of the randomization factor may result in a larger value for the twist velocity parameter.

[0066] For example, if the ply color distribution is set to be randomized, a seed position input window 640 for determining the arc parameters may be activated. The seed position value is entered through the activated seed position input window 640. The seed position may be a parameter for which the random parameter determines the distribution of the arc parameters. The value of the arc parameter for each yarn may be randomly determined such that the larger the seed position value, the greater the distribution of the arc parameter values ​​for each yarn. The larger the seed position value, the greater the randomness of the color distribution of the knit structure.

[0067] As an example, the physical property data of knitwear may include plynormal map data. A plynormal map for yarn simulation is determined via the plynormal map input window 650. The knitwear can be simulated to include surface features indicated by the plynormal map input via the input window 650.

[0068] As an example, the physical property data of knitwear may include information on the number of plies (ply amount) contained in the yarn. The number of plies contained in the yarn is determined via the input window 660 for the number of plies. The yarn of the knitwear may be simulated in a form in which the number of plies entered via the input window 660 are twisted.

[0069] As an example, the physical property data of knitwear may include information on the color of each ply contained in the yarn. The ply color input window 670 may be generated only for the number of plies entered via the ply number input window 660. The color of each ply contained in the yarn is determined via the ply color input window 670. The yarn of the knitwear may be simulated in a form in which the plies of the colors entered via the ply color input window 670 are twisted.

[0070] As an example, the physical property data of knitwear may include information about the direction of the knit structure (e.g., knit direction). The direction of the knit structure is determined via the knit structure direction input window 680. The knitwear may be simulated in the direction of the knit structure entered via the input window 680.

[0071] 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 information on the knit structure type (e.g., stitching type) and density information (e.g., gauge). The interface includes a knit structure type setting window 691 and a density input window 692.

[0072] Figures 7a to 12 illustrate a knitting simulation method for a yarn base according to one embodiment.

[0073] 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 310 to 330 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] JPEG2026524589000002.jpg46168

[0078] During optimization, the kinematics of the position of the yarn vertex can be expressed by the following equations 1 and 2.

[0079]

number

number

[0080] JPEG2026524589000005.jpg52168

[0081] JPEG2026524589000006.jpg36168

[0082]

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[0083] To calculate the rotation matrix R, the derivative of the normal vector ∇n is calculated as shown in equation 4 below.

[0084]

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[0085] As shown in equation 5, a, b, and r are calculated.

[0086]

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[0087] As shown in equation 6, R(X1, X2) is calculated.

[0088]

number

[0089] JPEG2026524589000011.jpg19168

[0090] JPEG2026524589000012.jpg58168

[0091] JPEG2026524589000013.jpg52168

[0092] An optimization process according to one embodiment may include a null space in which the yarn can slide. In other words, the elastic energy E of a periodic yarn 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 yarn 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 yarn may be generated by interpolating between two sliding states.

[0093] 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.

[0094] 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.

[0095]

number

[0096] In equation 7, N is the undeformed normal vector to the boundary of the garment pattern, and this is 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.

[0097] 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.

[0098] 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.

[0099] The first basic shape I is reparameterized using a three-dimensional function as shown in Equation 8, based on in-plane strains.

[0100]

number

[0101] 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 y Sampling 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.

[0102] 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.

[0103] JPEG2026524589000016.jpg25168

[0104] JPEG2026524589000017.jpg23168

[0105] JPEG2026524589000018.jpg777

[0106]

number

[0107] In equation 9, Φ is the deformed midsurface, and n is the normal vector of the midsurface.

[0108] A gradient is defined as shown in equation 10.

[0109]

number

[0110] By definition ∇ Φ This is shown in equation 11.

[0111]

number

[0112] JPEG2026524589000022.jpg14168

[0113]

number

[0114] JPEG2026524589000024.jpg35168

[0115]

number

[0116] JPEG2026524589000026.jpg21168

[0117]

number

[0118] In the rest pose, I = Id, II = 0, and ΔQ = 0.

[0119] For each vertex i of each yarn pattern and 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 the yarn. When interpolation is performed on the displacements of the deformation state samples, a yarn-level displacement map is obtained for the given in-plane deformations s xj 、s aj 、s yj . For the deformation rates directly sampled in the database of ΔQ, the exact yarn pattern is restored, and for the intermediate deformation rates of the sampled deformation rates, an approximate pattern is generated.

[0120] The database of the displacements of the yarn patterns for various deformation states is applied to the yarn patterns tiled on the triangular mesh during animation.

[0121] JPEG2026524589000028.jpg34168

[0122] As an example, Algorithm 1 illustrated in FIG. 11 includes the process of rendering q corresponding to an input including mesh animation, yarn pattern, and displacement ΔQ.

[0123] 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.

[0124] For each animation frame, discrete fundamental forms I and II for each mesh are calculated as shown in equation 15 below.

[0125]

number

[0126] In Equation 15, F is the deformation gradient of the mesh, and Λ is the triangle-averaged shape operator. Using modified Shepard weights, I and II may be distributed to the vertices of the triangular mesh. 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.

[0127] According to one embodiment, the effect of bending behavior is approximated by adding stretching and compression through surface curvature.

[0128] 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.

[0129]

number

[0130] 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.

[0131]

number

[0132] JPEG2026524589000032.jpg18168

[0133]

number

[0134] 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.

[0135]

number

[0136] 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.

[0137]

number

[0138] 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.

[0139] 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.

[0140] 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 large-scale overall deformations caused by the triangular mesh.

[0141] 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.

[0142]

number

[0143] 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.

[0144] Equation 22 can be used to map the yarn vertex to world space x.

[0145]

number

[0146] 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.

[0147] JPEG2026524589000038.jpg18168

[0148] 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.

[0149] 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.

[0150] Figure 13 is an illustrative diagram of the configuration of an electronic device according to one embodiment.

[0151] 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.).

[0152] A processor 1301 according to one embodiment may include at least one processor, which includes processing circuitry.

[0153] 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 may perform at least one of the following operations: determining the texture of yarn corresponding to multiple plies of different colors based on the twist speed parameter of the yarn corresponding to the knitwear; and generating rendering information for knitwear by simulating a garment pattern corresponding to knitwear on which the yarn with the determined texture is arranged.

[0154] 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.

[0155] 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.

[0156] 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.

[0157] 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 performs the following operations: determining the texture of yarn corresponding to multiple plies of different colors based on the twist rate parameter corresponding to the knitwear, and simulating a garment pattern corresponding to the knitwear on which the yarns of the determined textures are arranged, thereby generating rendering information for the knitwear.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] Software may include computer programs, code, instructions, or any combination thereof, which can configure or instruct a processing unit as desired, independently or collectively. 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.

[0162] 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.

[0163] 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.

[0164] 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.

[0165] 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 determining the texture of the yarn corresponding to multiple plies of different colors based on the twist speed parameter of the yarn corresponding to the knitwear, The steps include generating rendering information for the knitwear by simulating a garment pattern corresponding to the knitwear on which the yarn of the determined texture is arranged, Methods that include...

2. The method according to claim 1, wherein the number of times a particular ply is shown in a certain section of the yarn is determined based on the twist speed parameter.

3. The method according to claim 1, wherein the twist speed parameter is determined based on user input.

4. The method according to claim 1, wherein the step of determining the texture of the yarn includes the step of determining the texture of the yarn based on the twist velocity parameter and the arc parameter of the yarn.

5. The method according to claim 4, wherein the arc parameter includes a random parameter that indicates the twist start position of the yarn.

6. The method according to claim 4, wherein the arc parameters of different yarns arranged in the garment pattern are determined to be different values ​​from each other.

7. The method according to claim 1, further comprising the step of mapping vertices on the centerline of the yarn to the mesh of the garment pattern.

8. The step of determining the texture of the yarn is: The steps include: tessellating the center line of the yarn with a cylinder mesh; The steps include determining the texture of the tessellated yarn corresponding to multiple plies of different colors based on the twist velocity parameter, The method according to claim 7, including the method described in claim 7.

9. The method according to claim 8, wherein the step of generating rendering information for the knitwear includes the step 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.

10. The step of mapping the vertex to the mesh of the 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 7, including the method described in claim 7.

11. The step of generating rendering information for the knitwear is: The steps include obtaining 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, The steps include generating rendering information for the knitwear based on the acquired world space position, The method according to claim 10, including the method described in claim 10.

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

13. 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, An operation to determine the texture of the yarn corresponding to multiple plies of different colors based on the twist speed parameter of the yarn corresponding to the knitwear, The operation involves simulating a garment pattern corresponding to the knitwear on which the yarn of the determined texture is arranged, thereby generating rendering information for the knitwear. An electronic device in which this is performed.

14. The electronic device according to claim 13, wherein the number of times a particular ply is shown in a certain section of the yarn is determined based on the twist speed parameter.

15. The electronic device according to claim 13, wherein the operation for determining the texture of the yarn includes the operation for determining the texture of the yarn based on the twist velocity parameter and the arc parameter of the yarn.

16. The electronic device according to claim 15, wherein the arc parameter includes a random parameter that indicates the twist start position of the yarn.

17. The electronic device according to claim 15, wherein the arc parameters of different yarns arranged in the garment pattern are determined to be different values ​​from each other.

18. The electronic device according to claim 13, wherein, when the instruction is executed by the at least one processor alone or jointly, the electronic device further performs the operation of mapping vertices on the centerline of the yarn to the mesh of the garment pattern.

19. The operation to determine the texture of the yarn is as follows: The operation of tessellating the center line of the yarn with a cylinder mesh, An operation to determine the texture of the tessellated yarn corresponding to multiple plies of different colors based on the aforementioned twist velocity parameter, The electronic device according to claim 18, including the electronic device according to claim 18.

20. The electronic device according to claim 19, wherein the operation for generating rendering information of the knitwear includes the operation of generating rendering information of 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.

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