A method and apparatus for determining lossless compression of three-dimensional meshes

Abstract

This invention relates to a method and apparatus for determining lossless compression of three-dimensional meshes. The method includes: performing a priori comparison between a mesh to be matched and a comparison mesh; determining whether the priori comparison results of the mesh to be matched and the comparison mesh are consistent; if they are inconsistent, the two meshes are not matched; if they are consistent, comparing the connection relationship between the mesh to be matched and the comparison mesh to determine the matching result of the two meshes. The lossless compression determination method for three-dimensional meshes of this invention adds the determination of mesh connection relationships, improving the determination of mesh connection relationships in lossless measurement and ensuring the completeness of lossless mesh measurement.

Description

Technical Field

[0001] This invention belongs to the field of non-destructive mesh compression detection and measurement technology, specifically relating to a method and apparatus for determining non-destructive compression of three-dimensional meshes. Background Technology

[0002] Existing lossless quality metrics use pixel-by-pixel and vertex-by-vertex comparisons to determine if the texture maps and mesh information of two meshes are identical. For texture maps, assuming both maps are the same size, pixel-by-pixel comparisons are made to check if the pixel values ​​of the texture maps of the two meshes are consistent. Regarding mesh information, existing lossless quality metrics assume that geometric coordinates and texture coordinates share a common set of connectivity relationships. If both meshes have the same number of triangles, triangles are extracted one by one from the original mesh in the input order. A triangle with consistent information is then searched for among the unvisited triangles in the comparison mesh. If a corresponding triangle is found, it is marked as visited in the comparison mesh. Triangles with consistent information are defined as having the same vertex information and the same normal vector. Vertex information includes all information about the vertices of the input mesh, such as geometric coordinates, texture coordinates, vertex color, and normal vector. If any aspect of the texture map or mesh information indicates inconsistency, the two meshes are considered not identical.

[0003] Existing technologies can only determine the vertex information of a mesh, but cannot determine the mesh connection relationship, and are not comprehensive enough for lossless mesh measurement. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this invention provides a method and apparatus for determining lossless compression of three-dimensional meshes. The technical problem to be solved by this invention is achieved through the following technical solution:

[0005] This invention provides a method for determining lossless compression of three-dimensional meshes, comprising:

[0006] A priori comparison is performed between the mesh to be matched and the comparison mesh to determine whether the priori comparison results of the mesh to be matched and the comparison mesh are consistent. If they are inconsistent, the two meshes are not matched.

[0007] If they match, the connection relationship between the grid to be matched and the comparison grid is compared to determine the matching result of the two grids.

[0008] The present invention also provides a three-dimensional mesh lossless compression determination device, comprising:

[0009] The prior comparison module is used to perform a prior comparison between the mesh to be matched and the comparison mesh, and outputs the mesh mismatch result when the prior comparison results of the mesh to be matched and the comparison mesh are inconsistent;

[0010] The connection relationship comparison module is used to compare the connection relationship between the mesh to be matched and the comparison mesh when the prior comparison results are consistent, and to determine the matching result of the two meshes. The connection relationship includes at least one of geometric coordinate connection relationship and texture coordinate connection relationship.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0012] The three-dimensional mesh lossless compression determination method of the present invention adds the determination of mesh connection relationship, improves the determination of mesh connection relationship in lossless measurement, and ensures the completeness of lossless mesh measurement.

[0013] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a three-dimensional mesh lossless compression determination method provided in an embodiment of the present invention;

[0015] Figure 2 This is a schematic diagram of a TFAN triangular fan provided in an embodiment of the present invention;

[0016] Figure 3 This is a schematic diagram of an Edgebreaker mode provided in an embodiment of the present invention;

[0017] Figure 4 This is a schematic diagram of the structure of a three-dimensional mesh lossless compression determination device provided in an embodiment of the present invention. Detailed Implementation

[0018] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following describes in detail a three-dimensional mesh lossless compression determination method and apparatus proposed according to the present invention, in conjunction with the accompanying drawings and specific embodiments.

[0019] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of specific embodiments in conjunction with the accompanying drawings. Through the description of the specific embodiments, a more in-depth and concrete understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the technical solutions of the present invention.

[0020] Firstly, embodiments of the present invention propose a method for determining lossless compression of three-dimensional meshes; please refer to [link to relevant documentation]. Figure 1 The diagram shows a method for determining the lossless compression of a three-dimensional mesh. The method for determining the lossless compression of a three-dimensional mesh in this embodiment includes the following steps:

[0021] Step 1: Perform a priori comparison between the mesh to be matched and the comparison mesh to determine whether the priori comparison results of the mesh to be matched and the comparison mesh are consistent;

[0022] Step 2: If they are inconsistent, the two meshes do not match; if they are consistent, the connection relationship between the mesh to be matched and the comparison mesh is compared to determine the matching result of the two meshes.

[0023] In one optional embodiment, the prior comparison includes, but is not limited to: comparing the texture maps of the two meshes, comparing the number of vertices, comparing the number of texture coordinates, and comparing the maximum number of adjacent triangles of a vertex. When all prior comparisons of the two meshes are consistent, the connection relationship between the two meshes is further compared.

[0024] In one optional embodiment, comparing the connectivity between the mesh to be matched and the comparison mesh includes:

[0025] If the geometric coordinates and texture coordinates of the mesh share a set of connection relationships, then any connection relationship in the geometric coordinate connection relationship and the texture coordinate connection relationship is compared; if the geometric coordinate connection relationship or texture coordinate connection relationship between the mesh to be matched and the mesh to be compared is consistent, then the two meshes match; otherwise, the two meshes do not match.

[0026] If the geometric coordinates and texture coordinates of the mesh have different connectivity relationships, then the geometric coordinate connectivity relationships and texture coordinate connectivity relationships are compared separately. If the geometric coordinate connectivity relationships and texture coordinate connectivity relationships of the mesh to be matched and the mesh to be compared are consistent, then the two meshes match; otherwise, the two meshes do not match.

[0027] In this embodiment, the comparison process between geometric coordinate connectivity and texture coordinate connectivity is similar. Therefore, the comparison between geometric coordinate connectivity and texture coordinate connectivity includes:

[0028] For the first vertex of the mesh to be matched, traverse the unmatched second vertices of the comparison mesh, compare the parameter information of the first mesh vertex with the parameter information of the second mesh vertex, until all the vertices and triangles of the mesh to be matched have been traversed, and determine the connection relationship between the mesh to be matched and the comparison mesh.

[0029] During the traversal, the grid state information of the grid to be matched is updated based on the matching result of the first grid vertex.

[0030] Optionally, the grid state information includes: the traversal status of triangles in the grid, the traversal status of vertices in the grid, the traversal order of vertices in the grid, and the number of vertices that have been visited in the grid.

[0031] In one optional embodiment, the connection relationship between the mesh to be matched and the comparison mesh is determined after all the mesh vertices and triangles of the mesh to be matched have been traversed, including:

[0032] After all the vertices and triangles of the mesh to be matched have been traversed, if the parameter information of the mesh to be matched is consistent with the parameter information of the comparison mesh, then the connection relationship between the mesh to be matched and the comparison mesh is consistent; otherwise, the connection relationship between the mesh to be matched and the comparison mesh is inconsistent.

[0033] In this embodiment, for the comparison of geometric coordinate connection relationships, the parameter information includes the geometric coordinates of the mesh vertices and the geometric coordinate connection relationships of the mesh represented by a preset traversal rule; for the comparison of texture coordinate connection relationships, the parameter information includes the texture coordinates of the mesh vertices and the texture coordinate connection relationships of the mesh represented by a preset traversal rule.

[0034] Alternatively, the mesh connectivity can be represented using a 3D mesh compression algorithm, such as the TFAN algorithm or Edgebreaker algorithm, or other mesh compression algorithms.

[0035] Furthermore, taking the comparison of the geometric coordinate connection relationship of the grid as an example, the comparison process using the TFAN algorithm is illustrated.

[0036] First, a brief introduction to the TFAN algorithm: TFAN is the most efficient 3D mesh compression algorithm in the international standard SC3DMC. It encodes 3D mesh connectivity using triangular sectors as units; it encodes point coordinates and attributes (including normal vectors, texture coordinates, and vertex colors) using quantization, prediction, and entropy coding methods. TFAN can encode arbitrary mesh structures and can compress connectivity without loss. However, quantization is a mandatory module when encoding point coordinates and attributes, so TFAN only supports lossy compression of point coordinates and attributes.

[0037] This algorithm defines a mesh structure called a Triangle Fan (TF), such as... Figure 2 As shown. All triangles in TF share a common vertex v7, which is the center of TF; every two consecutive triangles in TF share a common edge; all triangles in TF have the same orientation, which refers to the direction in which the vertices of the triangle are traversed.

[0038] The TFAN algorithm divides the 3D mesh into a cluster of TFs and defines 10 TF patterns, using these patterns to represent the traversal order of the TFs. Since each TF already contains the connection relationships of its vertices, the encoder and decoder can obtain the vertex traversal order of the entire mesh by traversing the center points of the TFAN in the same order, ensuring that the encoder and decoder obtain the same vertex traversal order. TFAN only needs to encode the pattern numbers as needed to represent the connection relationships of the entire mesh. This connection-driven encoding method employed by TFAN ensures that the encoding of geometric information and UV coordinates follows the encoding order of the connection information. During the encoding of geometric and UV coordinates, parallelogram prediction and similar triangle prediction are performed on the geometric and UV coordinates respectively according to the vertex order encoded by the connection relationships, and the prediction residuals are entropy encoded.

[0039] In one optional embodiment, the specific process of comparing the geometric coordinate connections of the meshes using the TFAN algorithm is as follows. For ease of description, the mesh to be matched is denoted as mesh A, and the mesh to be compared is denoted as mesh B.

[0040] a: Construct the first TFAN with any first vertex in grid A as the center point, and update the state information of grid A.

[0041] b: In grid B, find whether there exists a point that matches the first grid vertex of grid A. Specifically, if the geometric coordinates of the second grid vertex in grid B and the second TFAN constructed with the second grid vertex as the center point are consistent with the first grid vertex and the first TFAN of grid A, then the second grid vertex is considered to be a matching point with the first grid vertex.

[0042] c: For each first grid vertex in grid A, traverse the unmatched second grid vertices in grid B to obtain the matching point status of each first grid vertex in grid A. The matching point status of the first grid vertex includes the following three cases: 0 represents no matching point; 1 represents one matching point; and greater than 1 represents multiple matching points.

[0043] During the traversal, if there is a matching point in grid B, then that matching point is selected as the matching grid point of the first grid vertex; if there are multiple matching points in grid B, then a matching point is randomly selected as the matching grid point of the first grid vertex, and the remaining matching points are saved as candidate matching grid points for the first grid vertex.

[0044] If there is no matching point in grid B, the matching grid point of the previous first grid vertex is modified. The specific modification process is as follows: if there is a candidate matching grid point for the previous first grid vertex, a candidate matching grid point is randomly selected as the matching grid point for the first grid vertex again, and the matching grid point before the modification is taken as the unmatched second grid vertex; if there is no candidate matching grid point for the previous first grid vertex, it is considered that the first grid vertex has no matching point in grid B.

[0045] d: Until all the vertices and triangles of grid A have been traversed, if the first vertex of grid A has a matching grid point in grid B, then the geometric connection between grid A and grid B is consistent; otherwise, the geometric connection between grid A and grid B is inconsistent.

[0046] It should be noted that if no matching point can be found in grid B for the initial first grid vertex in grid A, then the geometric coordinate connection relationship between grid A and grid B is considered to be inconsistent.

[0047] Furthermore, the process of finding a matching point in grid B for the first grid vertex of grid A is explained in detail.

[0048] First, for the first vertex of mesh A, construct the first TFAN with the first vertex as the center point (note that there may be multiple TFANs constructed at this point due to the existence of non-manifold structures), and save the state information of the TFAN (including: 1. TFAN mode, 2. TFAN degree, 3. vertex traversal information, 4. vertex relative index information, 5. traversal order of mesh vertices). At the same time, save the starting face and the next face of the first TFAN constructed at the first mesh point (to determine the order of TFANs).

[0049] Then, iterate through the second unmatched grid vertex in grid B, compare the geometric coordinates of the two grid vertices. If the geometric coordinates are the same, compare whether the TFAN constructed based on the two grid vertices are the same. If they are the same, the two grid vertices are matched. If they are different, the two grid vertices are considered to be unmatched.

[0050] In this embodiment, the comparison of TFANs specifically includes: transmitting the information of the starting face and the next face of the first TFAN constructed using the first mesh vertex to mesh B; constructing a second TFAN based on the second mesh vertex of mesh B; and comparing the five state information of the first TFAN and the second TFAN. If all five state information are the same, the second TFAN is considered to be consistent with the first TFAN; otherwise, the two TFANs are considered to be inconsistent.

[0051] It is worth noting that when constructing the second TFAN at the second vertex of mesh B, multiple overlapping faces may result in multiple second TFANs. Therefore, it is necessary to compare the first TFAN with each second TFAN to confirm their consistency. When multiple first TFANs are constructed with the first vertex as the center point, the starting face and next face information of each first TFAN need to be transmitted to mesh B. This allows the second vertex of mesh B to construct the corresponding second TFAN based on the information. If each first TFAN has a consistent second TFAN, then the first TFAN constructed with that first vertex as the center is considered consistent with the second TFAN constructed with the second vertex as the center.

[0052] The process of comparing the texture coordinate connection relationship of the mesh using the TFAN algorithm is similar to that of comparing the geometric coordinate connection relationship, and will not be elaborated here.

[0053] Furthermore, taking the comparison of the geometric coordinate connection relationship of the mesh as an example, the comparison process using the Edgebreaker algorithm is illustrated.

[0054] First, a brief introduction to the Edgebreaker algorithm: The Edgebreaker algorithm is a 3D mesh connectivity encoding method with advantages such as good compression performance, ease of implementation, and the ability to provide an upper limit for the compression ratio. The Edgebreaker method itself only describes the compression method for 3D mesh connectivity information; geometric information compression and entropy encoding are also required to achieve true compression of the 3D mesh.

[0055] The Edgebreaker encoding algorithm uses five different modes (called C, L, E, R, and S) to represent the connectivity of a 3D mesh. During the encoding process, each triangle of the mesh is accessed in depth-first order, and each triangle is labeled according to its mode, generating a CLERS string to obtain a compact representation of the mesh connectivity.

[0056] Please see Figure 3 A diagram illustrating the Edgebreaker pattern, showing the five modes of the Edgebreaker method as follows: Figure 3As shown, the 3D mesh is divided into traversed and untraversed parts, and the boundary between the two parts is called the active boundary. During the Edgebreaker coding process, the triangles to be traversed are accessed by traversing the active edges on the active boundary. The mode used is selected based on the relationship between the active edge and the triangle it belongs to. Specifically, if the third vertex of the triangle connected to the active edge is not on the active boundary, the current triangle is marked as C mode; if the third vertex is on the active boundary and is the next vertex of the current active edge in counter-clockwise order, the current triangle is marked as R mode; if the third vertex is on the active boundary and is the previous vertex of the current active edge in counter-clockwise order, the current triangle is marked as L mode; if the third vertex is on the active boundary and is both the previous and next vertex of the current active edge in counter-clockwise order, the current triangle is marked as E mode; if the third vertex is on the active boundary but is neither the previous nor the next vertex of the current active edge in counter-clockwise order, the current triangle is marked as S mode.

[0057] After marking each triangle, the active boundary is updated, and the next active edge is selected according to certain rules. After traversing all triangles, the corresponding CLERS string is entropy encoded, which can achieve higher compression efficiency.

[0058] In one optional embodiment, the specific process of comparing the geometric coordinate connections of the meshes using the Edgebreaker algorithm is as follows. For ease of description, the mesh to be matched is denoted as mesh A, and the mesh to be compared is denoted as mesh B.

[0059] For mesh A, select an initial triangle and determine its mode type based on the vertex traversal, then update the state information of mesh A. In mesh B, find triangles with matching geometric coordinates and compare their mode types. Using the Edgebreaker's traversal rules, sequentially traverse all untraversed triangles in the mesh and obtain mode strings representing connection relationships. Compare the mode strings of mesh A and mesh B with the geometric coordinates of the corresponding vertices of the triangles. If the geometric coordinates and mode strings match, the connection relationship between the two meshes is considered consistent; otherwise, the connection relationship is considered inconsistent.

[0060] The process of comparing the texture coordinate connection relationship of the mesh using the Edgebreaker algorithm is similar to that of comparing the geometric coordinate connection relationship, and will not be elaborated here.

[0061] The three-dimensional mesh lossless compression determination method of this invention adds a judgment on mesh connectivity for lossless mesh compression detection, solving the problem of missing mesh connectivity judgment in lossless mesh compression detection, improving the judgment of mesh connectivity in lossless measurement, and ensuring the completeness of lossless mesh measurement. Furthermore, it also solves the problem when geometry and texture have two sets of connectivity relationships in the three-dimensional mesh lossless compression determination.

[0062] Secondly, corresponding to the three-dimensional mesh lossless compression determination method proposed in the first aspect, this embodiment of the invention proposes a three-dimensional mesh lossless compression determination device. Please refer to [link to relevant documentation]. Figure 4 The lossless compression determination device for the 3D mesh includes:

[0063] The prior comparison module 100 is used to perform prior comparison between the mesh to be matched and the comparison mesh, and outputs the result of mesh mismatch when the prior comparison results of the mesh to be matched and the comparison mesh are inconsistent.

[0064] The connection relationship comparison module 200 is used to compare the connection relationship between the mesh to be matched and the comparison mesh when the prior comparison results are consistent, and to determine the matching result of the two meshes. The connection relationship includes at least one of geometric coordinate connection relationship and texture coordinate connection relationship.

[0065] For details regarding the three-dimensional mesh lossless compression determination device and its corresponding beneficial effects, please refer to the relevant content of the three-dimensional mesh lossless compression determination method provided in the first aspect, which will not be repeated here.

[0066] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes said element. Terms such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0067] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for lossless compression decision of a three-dimensional mesh, characterized in that, The method comprises the following steps: comparing the priori of the to-be-matched mesh and the contrast mesh, judging whether the priori comparison result of the to-be-matched mesh and the contrast mesh is consistent, if not, the two meshes are not matched; if consistent, comparing the connection relationship of the to-be-matched mesh and the contrast mesh, and determining the matching result of the two meshes; the connection relationship comprises at least one of the geometric coordinate connection relationship and the texture coordinate connection relationship, and the comparison of the connection relationship of the to-be-matched mesh and the contrast mesh comprises: if the geometric coordinates and the texture coordinates of the mesh share a set of connection relationship, any one of the geometric coordinate connection relationship and the texture coordinate connection relationship is compared; if the geometric coordinate connection relationship or the texture coordinate connection relationship of the to-be-matched mesh and the contrast mesh is consistent, the two meshes are matched, otherwise the two meshes are not matched; if the geometric coordinates and the texture coordinates of the mesh have different connection relationships, the geometric coordinate connection relationship and the texture coordinate connection relationship are compared respectively, if the geometric coordinate connection relationship and the texture coordinate connection relationship of the to-be-matched mesh and the contrast mesh are consistent, the two meshes are matched, otherwise the two meshes are not matched; wherein, the comparison of any one of the geometric coordinate connection relationship and the texture coordinate connection relationship comprises: for the first mesh vertex of the to-be-matched mesh, the un-matched second mesh vertex of the contrast mesh is traversed, the parameter information of the first mesh vertex is compared with the parameter information of the second mesh vertex until the mesh vertex and the triangle of the to-be-matched mesh are traversed, and the connection relationship comparison result of the to-be-matched mesh and the contrast mesh is determined; wherein, the mesh state information of the to-be-matched mesh is updated according to the matching result of the first mesh vertex in the traversal process; for the comparison of the geometric coordinate connection relationship, the parameter information comprises the geometric coordinates of the mesh vertex and the geometric coordinate connection relationship of the mesh represented by the preset traversal rule; for the comparison of the texture coordinate connection relationship, the parameter information comprises the texture coordinates of the mesh vertex and the texture coordinate connection relationship of the mesh represented by the preset traversal rule.

2. The method of claim 1, wherein, The priori comparison comprises: texture map comparison, vertex number comparison, texture coordinate number comparison, and maximum number of adjacent triangles of vertices comparison.

3. The method of claim 1, wherein, The mesh state information comprises: the traversal situation of the triangle in the mesh, the traversal situation of the vertex in the mesh, the traversal order of the vertex in the mesh, and the number of the vertices in the mesh which have been visited.

4. The method of claim 1, wherein, Until the mesh vertex and the triangle of the to-be-matched mesh are traversed, the connection relationship comparison result of the to-be-matched mesh and the contrast mesh is determined, comprising: when the mesh vertex and the triangle of the to-be-matched mesh are traversed, if the parameter information of the to-be-matched mesh is consistent with the parameter information of the contrast mesh, the connection relationship of the to-be-matched mesh and the contrast mesh is consistent; otherwise, the connection relationship of the to-be-matched mesh and the contrast mesh is inconsistent.

5. A three-dimensional mesh lossless compression decision device, characterized by, ​ The prior comparison module is configured to compare the to-be-matched mesh and the comparison mesh in priori, and output a result of mesh mismatching when the prior comparison result of the to-be-matched mesh and the comparison mesh is inconsistent. The connection relationship comparison module is configured to compare the connection relationship of the to-be-matched mesh and the comparison mesh when the prior comparison result of the to-be-matched mesh and the comparison mesh is consistent, and determine the matching result of the two meshes, wherein the connection relationship includes at least one of a geometric coordinate connection relationship and a texture coordinate connection relationship. The connection relationship comparison module is configured to compare the connection relationship of the to-be-matched mesh and the comparison mesh when the prior comparison result of the to-be-matched mesh and the comparison mesh is consistent, and determine the matching result of the two meshes, wherein the connection relationship includes at least one of a geometric coordinate connection relationship and a texture coordinate connection relationship. If the geometric coordinates and the texture coordinates of the mesh share a set of connection relationship, any connection relationship of the geometric coordinate connection relationship and the texture coordinate connection relationship is compared; if the geometric coordinate connection relationship or the texture coordinate connection relationship of the to-be-matched mesh and the comparison mesh is consistent, the two meshes are matched, otherwise the two meshes are not matched. If the geometric coordinates and the texture coordinates of the mesh have different connection relationships, the geometric coordinate connection relationship and the texture coordinate connection relationship are compared respectively; if the geometric coordinate connection relationship and the texture coordinate connection relationship of the to-be-matched mesh and the comparison mesh are consistent, the two meshes are matched, otherwise the two meshes are not matched. The comparison of any connection relationship of the geometric coordinate connection relationship and the texture coordinate connection relationship includes: For a first mesh vertex of the to-be-matched mesh, a second mesh vertex of the comparison mesh which is not matched is traversed, and the parameter information of the first mesh vertex is compared with the parameter information of the second mesh vertex until the mesh vertex and the triangle of the to-be-matched mesh are traversed, and the connection relationship comparison result of the to-be-matched mesh and the comparison mesh is determined; wherein the mesh state information of the to-be-matched mesh is updated according to the matching result of the first mesh vertex in the traversal process; For the comparison of the geometric coordinate connection relationship, the parameter information includes the geometric coordinates of the mesh vertex and the geometric coordinate connection relationship of the mesh represented by a preset traversal rule; for the comparison of the texture coordinate connection relationship, the parameter information includes the texture coordinates of the mesh vertex and the texture coordinate connection relationship of the mesh represented by a preset traversal rule.

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