Point-by-point coordinate conversion method and device for udb format bim model data

Abstract

The application discloses a UDB format BIM model data point-by-point coordinate conversion method and device, which comprises the following steps: step S1: data acquisition; step S2: component data processing; step S3: global coordinate conversion; step S4: model component and data set reconstruction; and step S5: data set output. The method is quick and easy to use, and users can add UDB three-dimensional model data through a window and set coordinate conversion information, so that the conversion of model geometric coordinate information and the transfer of model attributes are automatically completed.

Description

Technical Field

[0001] This application relates to the field of image data format conversion technology, and in particular to a method and apparatus for point-by-point coordinate conversion of UDB format BIM model data. Background Technology

[0002] SuperMap platform has become one of the main basic platforms for BIM+GIS technology application development in China. It is widely used in the construction and development of engineering BIM+GIS information construction basic platforms because it adopts mature data processing technology, relatively complete data processing software, mature desktop data processing secondary development basic platform and mature WebGL-based basic development platform.

[0003] However, because SuperMap's BIM data processing software is constantly being updated, some functions are incomplete, such as coordinate transformation. Existing BIM data processing software can only transform the coordinates of the center of a single feature set component model, and cannot perform point-by-point transformations of the coordinates of model vertices, material maps, normals, etc.

[0004] Therefore, when using the original BIM model as the independent coordinate system for various projects, it is necessary to convert the original BIM model to a unified coordinate system (such as CGCS2000). However, due to the projection distortion between the independent coordinate system and the target coordinate system, converting the component center coordinates of the dataset separately can cause linear (such as water diversion tunnels) BIM models to be unable to connect with other models at the beginning and end, making it difficult to integrate BIM and GIS data. This is especially true in the application of BIM+GIS information technology in high-altitude linear projects, where it is impossible to construct a BIM+GIS engineering data map on a single map.

[0005] Therefore, how to solve the conversion of BIM model coordinate data based on UDB format is currently a key issue and technical challenge in BIM+GIS data fusion based on the SuperMap platform. Summary of the Invention

[0006] This application addresses the technical problems of projection distortion after coordinate data conversion of UDB-format BIM models, inability of the beginning and end of the BIM model to connect with other models after transforming the center coordinates, and difficulty in integrating BIM and GIS data. It provides a point-by-point coordinate conversion method for UDB-format BIM model data to realize vertex coordinate conversion of UDB-format BIM models.

[0007] This application provides a point-by-point coordinate conversion method for UDB format BIM model data, including the following steps:

[0008] Step S1: Obtain data: Load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data shall contain at least one skeleton data and component center coordinates.

[0009] Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components;

[0010] Step S2: Component data processing: Process the construction data obtained in step S1, including the transformation of the center coordinates of each component, and obtaining the global coordinates of the normal vector, the global coordinates of the model material map, and the global coordinates of the model vertices;

[0011] The aforementioned component center coordinate processing refers to the provision of a center coordinate (x, y) for each component in the UDB data structure. c y c , z c Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point (x). cd y cd , z cd ).

[0012] The acquisition of various global coordinates for each component refers to, taking the acquisition of vertex global coordinates as an example, the vertex global coordinates (x, y, z) data of the UDB model are obtained through a series of transformations, that is, the vertex coordinates (x, y, z) are obtained through a series of transformations. o y o , z o ), center coordinates (x) c y c , z c The transformation matrix R and the transformation matrix R satisfy the following relationship:

[0013]

[0014] Material map coordinates (u o v o The material map's global coordinates (u, v) satisfy the following:

[0015]

[0016] Step S3: Global coordinate transformation, obtain the target's global coordinates (x... d y d , z d And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction;

[0017] Transformation matrix reconstruction: The transformation matrix of the reconstructed model components is replaced by the identity matrix. That is, R d satisfy:

[0018]

[0019] Model geometric information reconstruction includes normal vector coordinate reconstruction, model material map coordinate reconstruction, and model vertex coordinate reconstruction. The normal vector coordinate and model vertex coordinate reconstruction processes are exactly the same. (The text then repeats the process of reconstructing model vertex coordinates, which is redundant and can be omitted.) dd y dd , z dd Taking reconstruction as an example, it satisfies:

[0020]

[0021] Model material texture coordinates (u dd v dd Refactoring, satisfying:

[0022]

[0023] Step S4: Model Components and Dataset Reconstruction: Reconstruct the model data based on the calculation results of the model data in Steps S2 and S3, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, then transfer component attributes and reconstruct the dataset;

[0024] Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component.

[0025] Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements.

[0026] Step S5: Dataset Output: Assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

[0027] Preferably, in step S5, assigning a new coordinate system means that after the model coordinate data is converted into new coordinates, the coordinate system information of the dataset needs to be updated. This can be done simply by creating a new coordinate system based on the EPSG number of the new coordinate system.

[0028] Preferably, global transformation refers to the transformation of data coordinates based on the transformation relationship between the original independent coordinates and the target coordinates.

[0029] Preferably, the global coordinate transformation and the central coordinate transformation are the same, both involving a standard coordinate system transformation of the global coordinates.

[0030] Preferably, both global coordinate transformation and center coordinate transformation adopt the 7-parameter method or the 4-parameter method.

[0031] Another aspect of this application provides a point-by-point coordinate transformation method for UDB format BIM model data as described above, including:

[0032] The data acquisition module is used to load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data must contain at least one skeleton data and component center coordinates.

[0033] Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components;

[0034] The component data processing module is used to process the acquired construction data, including the transformation of the center coordinates of each component, and the acquisition of global coordinates of the normal vector, global coordinates of the model material texture, and global coordinates of the model vertices.

[0035] The aforementioned component center coordinate processing refers to the provision of a center coordinate (x, y) for each component in the UDB data structure. c y c , z c Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point (x). cd y cd , z cd ).

[0036] The acquisition of various global coordinates for each component refers to, taking the acquisition of vertex global coordinates as an example, the vertex global coordinates (x, y, z) data of the UDB model are obtained through a series of transformations, that is, the vertex coordinates (x, y, z) are obtained through a series of transformations. o y o , z o ), center coordinates (x) c y c , z c The transformation matrix R and the transformation matrix R satisfy the following relationship:

[0037]

[0038] Material map coordinates (u o v o The material map's global coordinates (u, v) satisfy the following:

[0039]

[0040] The global coordinate transformation module is used to obtain the target's global coordinates (x, y, y). d y d , z d And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction;

[0041] The transformation matrix is ​​reconstructed, and the transformation matrix of the reconstructed model components is replaced by the identity matrix. That is, Rd satisfies:

[0042]

[0043] Model geometric information reconstruction includes normal vector coordinate reconstruction, model material map coordinate reconstruction, and model vertex coordinate reconstruction. The normal vector coordinate and model vertex coordinate reconstruction processes are exactly the same. (The text then repeats the process of reconstructing model vertex coordinates, which is redundant and can be omitted.) dd y dd , z dd Taking reconstruction as an example, it satisfies:

[0044]

[0045] Model material texture coordinates (u dd v dd Refactoring, satisfying:

[0046]

[0047] The model component and dataset reconstruction module is used to reconstruct the model data based on the calculation results of the obtained model data, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, and then transfer component attributes and reconstruct the dataset.

[0048] Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component.

[0049] Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements.

[0050] The dataset output module is used to assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

[0051] The beneficial effects that this application can produce include:

[0052] 1) The point-by-point coordinate transformation method for UDB format BIM model data provided in this application is quick and easy to use. Users can add UDB 3D model data through the window and set coordinate transformation information to automatically complete the transformation of model geometric coordinate information and the transfer of model attributes.

[0053] 2) The point-by-point coordinate conversion method for UDB format BIM model data provided in this application has strong scalability. Through this method, the coordinate data of UDB format BIM model can be quickly converted between any two coordinate systems.

[0054] 3) The point-by-point coordinate transformation method for UDB format BIM model data provided in this application realizes the integration of BIM+GIS data based on the SuperMap platform. BIM can flexibly embed coordinate transformation algorithms, which solves the problem of point-by-point coordinate transformation of UDB format BIM data with multiple independent engineering coordinates, thereby promoting the application of BIM+GIS technology in engineering information construction. Attached Figure Description

[0055] Figure 1 A schematic diagram illustrating the point-by-point coordinate transformation method for UDB format BIM model data provided in this application;

[0056] Figure 2 A schematic diagram of the point-to-point coordinate conversion device module for UDB format BIM model data provided in this application;

[0057] Figure 3 The following are schematic diagrams of the results obtained in the embodiments of this application; wherein a) is a diagram of the treatment results of the Xiaoyuba inverted siphon section of the Dianzhong Water Diversion Project; b) is a diagram of the treatment results of the Songlin aqueduct section of the Dianzhong Water Diversion Project; c) is a diagram of the treatment results of the Jiudaohe inverted siphon section of the Dianzhong Water Diversion Project; d) is a diagram of the treatment results of the Luzhihe aqueduct section of the Dianzhong Water Diversion Project. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0059] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0060] Technical means not detailed in this application and not used to solve the technical problems of this application are all set according to common general knowledge in the field, and multiple common general knowledge setting methods can be implemented.

[0061] The UDB file format described in this application is a 3D data exchange format provided by SuperMap. The UDB format is not open source. SuperMap provides an SDK based on development tools such as C++ and C# to realize the reading, writing, modification and conversion operations of UDB 3D BIM model data.

[0062] See Figure 1 The point-by-point coordinate conversion method for UDB format BIM model data provided in this application includes the following steps:

[0063] Step S1: Obtain data: Load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data shall contain at least one skeleton data and component center coordinates.

[0064] Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components;

[0065] Step S2: Component data processing: Process the construction data obtained in step S1, including the transformation of the center coordinates of each component, and obtaining the global coordinates of the normal vector, the global coordinates of the model material map, and the global coordinates of the model vertices;

[0066] The aforementioned component center coordinate processing refers to the provision of a center coordinate (x, y) for each component in the UDB data structure. c y c , z c Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point (x). cd y cd , z cd ).

[0067] The acquisition of various global coordinates for each component refers to, taking the acquisition of vertex global coordinates as an example, the vertex global coordinates (x, y, z) data of the UDB model are obtained through a series of transformations, that is, the vertex coordinates (x, y, z) are obtained through a series of transformations. o y o , z o ), center coordinates (x) c y c , z c The transformation matrix R and the transformation matrix R satisfy the following relationship:

[0068]

[0069] Wherein, the global coordinates of the normal vector (x) f y f , z f ) and local coordinates (x) f0 y f0 , z f0 The transformation between ) is consistent with the vertex coordinate transformation method, that is:

[0070]

[0071] Material map coordinates (u ov o The material map's global coordinates (u, v) satisfy the following:

[0072]

[0073] Step S3: Global coordinate transformation, obtain the target's global coordinates (x... d y d , z d And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction;

[0074] The transformation matrix is ​​reconstructed, and the transformation matrix of the reconstructed model components is replaced by the identity matrix. That is, Rd satisfies:

[0075]

[0076] Model geometric information reconstruction includes normal vector coordinate reconstruction, model material map coordinate reconstruction, and model vertex coordinate reconstruction. The normal vector coordinate and model vertex coordinate reconstruction processes are exactly the same. (The text then repeats the process of reconstructing model vertex coordinates, which is redundant and can be omitted.) dd y dd , z dd Taking reconstruction as an example, it satisfies:

[0077]

[0078] Model material texture coordinates (u dd v dd Refactoring, satisfying:

[0079]

[0080] Step S4: Model Components and Dataset Reconstruction: Reconstruct the model data based on the calculation results of the model data in Steps S2 and S3, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, then transfer component attributes and reconstruct the dataset;

[0081] Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component.

[0082] Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements.

[0083] Step S5: Dataset Output: Assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

[0084] In this context, assigning a new coordinate system means that after the model coordinate data is converted into the new coordinate system, the coordinate system information of the dataset needs to be updated. This can be done simply by creating a new coordinate system based on the EPSG number of the new coordinate system.

[0085] In one specific embodiment, global transformation refers to the transformation of data coordinates based on the transformation relationship between the original independent coordinates and the target coordinates. Global coordinate transformation is consistent with central coordinate transformation, i.e., performing a standard coordinate system transformation on the global coordinates. Commonly used methods such as the 7-parameter method, 4-parameter method, or affine transformation can be employed. This invention provides a reserved interface for flexible embedding of these methods.

[0086] See Figure 2 Another aspect of this application provides a point-by-point coordinate transformation method for UDB format BIM model data as described above, comprising:

[0087] The data acquisition module is used to load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data must contain at least one skeleton data and component center coordinates.

[0088] Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components;

[0089] The component data processing module is used to process the acquired construction data, including the transformation of the center coordinates of each component, and the acquisition of global coordinates of the normal vector, global coordinates of the model material texture, and global coordinates of the model vertices.

[0090] The aforementioned component center coordinate processing refers to the provision of a center coordinate (x, y) for each component in the UDB data structure. c y c , z c Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point (x). cd y cd , z cd ).

[0091] The acquisition of various global coordinates for each component refers to, taking the acquisition of vertex global coordinates as an example, the vertex global coordinates (x, y, z) data of the UDB model are obtained through a series of transformations, that is, the vertex coordinates (x, y, z) are obtained through a series of transformations. o y o , z o ), center coordinates (x) c y c , z c The transformation matrix R and the transformation matrix R satisfy the following relationship:

[0092]

[0093] Material map coordinates (u o v o The material map's global coordinates (u, v) satisfy the following:

[0094]

[0095] The global coordinate transformation module is used to obtain the target's global coordinates (x, y, y). d y d , z d And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction;

[0096] The transformation matrix is ​​reconstructed, and the transformation matrix of the reconstructed model components is replaced by the identity matrix. That is, Rd satisfies:

[0097]

[0098] Model geometric information reconstruction includes normal vector coordinate reconstruction, model material map coordinate reconstruction, and model vertex coordinate reconstruction. The normal vector coordinate and model vertex coordinate reconstruction processes are exactly the same. (The text then repeats the process of reconstructing model vertex coordinates, which is redundant and can be omitted.) dd y dd , z dd Taking reconstruction as an example, it satisfies:

[0099]

[0100] Model material texture coordinates (u dd v dd Refactoring, satisfying:

[0101]

[0102] The model component and dataset reconstruction module is used to reconstruct the model data based on the calculation results of the obtained model data, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, and then transfer component attributes and reconstruct the dataset.

[0103] Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component.

[0104] Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements.

[0105] The dataset output module is used to assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

[0106] This device can quickly integrate BIM and GIS without any projection distortion after integration.

[0107] Example

[0108] like Figure 1 As shown, this invention provides a method for point-by-point coordinate transformation of UDB format BIM model data, the method comprising the following steps:

[0109] Step S1: Load the UDB SDK dynamic link library, parse and obtain various data of the UDB 3D model file. The obtained data includes: component data, model attribute information and index. The component data must contain at least one skeleton data and component center coordinates.

[0110] Skeleton data includes: vertex coordinates, normal coordinates, and material map coordinates of model components;

[0111] Step S2: Transform the center coordinates of each component, obtain the global coordinates of the normal vector, obtain the global coordinates of the model material texture, and obtain the global coordinates of the model vertices;

[0112] The component center coordinate transformation includes the following steps: In the UDB data structure, for each component's center coordinate (x... c y c , z c Perform a coordinate system transformation for the target measurement and obtain the transformation center point (x). cd y cd , z cd );

[0113] Obtaining the various global coordinates of each component involves the following steps: Taking the acquisition of vertex global coordinates as an example, the vertex global coordinates (x, y, z) data of the UDB model are obtained through a series of transformations, that is, the vertex coordinates (x, y, z) are obtained from the global coordinates of each component. o y o , z o ), center coordinates (x) c y c , z c The transformation matrix R and the transformation matrix R satisfy the following relationship:

[0114]

[0115] The normal vector coordinates and vertex coordinates are transformed in the same way, while the material map coordinates (u) o v o The material map's global coordinates (u, v) satisfy the following:

[0116]

[0117] Step S3: Obtain the target's global coordinates (x) d y d , z d ), and perform transformation matrix reconstruction of model component data and reconstruction of model geometric information.

[0118] Global coordinate transformation includes the following steps: Based on the transformation relationship between the original independent coordinates and the target coordinates, data coordinate transformation is achieved. Global coordinate transformation is consistent with central coordinate transformation, i.e., a standard coordinate system transformation is performed on the global coordinates. Commonly used methods such as the 7-parameter method, 4-parameter method, or affine transformation can be employed. These methods can be flexibly embedded through the interface reserved in this invention.

[0119] Transformation matrix reconstruction includes the following steps: the transformation matrix of the reconstructed model components is replaced by the identity matrix. That is, R... d Satisfy the following formula:

[0120]

[0121] Model geometric information reconstruction includes: normal vector coordinate reconstruction, model material map coordinate reconstruction, and model vertex coordinate reconstruction. The normal vector coordinate and model vertex coordinate reconstruction processes are exactly the same. (The text then repeats the process of reconstructing model vertex coordinates, which is redundant and can be omitted.) dd y dd , z dd Taking reconstruction as an example, the model vertex coordinates (x) dd y dd , z dd )satisfy:

[0122]

[0123] And the model material texture coordinates (u dd v dd Refactoring, satisfying:

[0124]

[0125] Step S4: Model component and dataset reconstruction: The model data calculation results in steps S2 and S3 are reconstructed, including: component center coordinate reconstruction, transformation matrix reconstruction and related skeleton data reconstruction, and then component attributes are transferred to obtain the reconstructed dataset;

[0126] Transferring component attributes means that, according to the UDB format model, each component corresponds to one set of attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component.

[0127] Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements.

[0128] Step S5: Dataset Output: Assign a new coordinate system to the reconstructed dataset and create a new dataset file under the current model data to complete the dataset output.

[0129] In this context, assigning a new coordinate system means that after the model coordinate data is converted into the new coordinate system, the coordinate system information of the dataset needs to be updated. This can be done simply by creating a new coordinate system based on the EPSG number of the new coordinate system.

[0130] The methods described in the above embodiments were applied to the Xiaoyuba inverted siphon section of the Dianzhong Water Diversion Project, and the resulting effect is shown in the figure below. Figure 3 As shown in a), the model can be accurately integrated with the terrain image after the model coordinate transformation, accurately showing the user its location and the surrounding terrain.

[0131] The methods described in the above embodiments were applied to the Songlin Aqueduct section of the Dianzhong Water Diversion Project, and the resulting effect is shown in the figure below. Figure 3 As shown in b), the model can be accurately integrated with the terrain image after the coordinate transformation, accurately showing the user its location and the surrounding terrain.

[0132] The methods described in the above embodiments were applied to the Jiudaohe inverted siphon section of the Dianzhong Water Diversion Project, and the resulting effect is shown in the figure below. Figure 3 As shown in c), the model can be accurately integrated with the terrain image after the model coordinate transformation, accurately showing the user its location and the surrounding terrain.

[0133] The methods described in the above embodiments were applied to the Luzhihe Aqueduct section of the Dianzhong Water Diversion Project, and the resulting effect is shown in the figure below. Figure 3 As shown in c), the model can be accurately integrated with the terrain image after the model coordinate transformation, accurately showing the user its location and the surrounding terrain.

[0134] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for point-by-point coordinate transformation of UDB format BIM model data, characterized in that, Includes the following steps: Step S1: Obtain data: Load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data shall contain at least one skeleton data and component center coordinates. Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components; Step S2: Component data processing: Process the construction data obtained in step S1, including transforming the center coordinates of each component, and obtaining global coordinates of the normal vector and global coordinates of the model vertices; The aforementioned component center coordinate processing refers to the provision of a center coordinate for each component in the UDB data structure. Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point. ; The acquisition of various global coordinates for each component refers to the acquisition of the vertex global coordinates of the UDB model. The data is obtained through a series of transformations, namely vertex coordinates. Center coordinates The transformation matrix R satisfies the following relationship: ; Step S3: Global coordinate transformation, obtain the target's global coordinates And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction; Transformation matrix reconstruction: The transformation matrix of the reconstructed model component is replaced by the identity matrix. That is, R d satisfy: Model geometric information reconstruction includes normal vector coordinate reconstruction and model vertex coordinate reconstruction. The process of normal vector coordinate reconstruction and model vertex coordinate reconstruction is exactly the same. Using model vertex coordinates Refactoring, satisfying: ; Step S4: Model Components and Dataset Reconstruction: Reconstruct the model data based on the calculation results of the model data in Steps S2 and S3, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, then transfer component attributes and reconstruct the dataset; Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component. Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements. Step S5: Dataset Output: Assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

2. The point-by-point coordinate conversion method for UDB format BIM model data according to claim 1, characterized in that, In step S5, assigning a new coordinate system means that after the model coordinate data is converted into new coordinates, the coordinate system information of the dataset needs to be updated. This can be done simply by creating a new coordinate system based on the EPSG number of the new coordinate system.

3. The point-by-point coordinate conversion method for UDB format BIM model data according to claim 1, characterized in that, Global transformation refers to the transformation of data coordinates based on the transformation relationship between the original independent coordinates and the target coordinates.

4. The point-by-point coordinate conversion method for UDB format BIM model data according to claim 1, characterized in that, The global coordinate transformation and the central coordinate transformation are the same operation, both of which are standard coordinate system transformations performed on the global coordinates.

5. The point-by-point coordinate conversion method for UDB format BIM model data according to claim 4, characterized in that, Both global coordinate transformation and center coordinate transformation use the 7-parameter method or the 4-parameter method.

6. A point-by-point coordinate conversion device for UDB format BIM model data according to any one of claims 1 to 5, characterized in that, include: The data acquisition module is used to load the UDB SDK dynamic link library, parse and obtain the component data, model attribute information and index of the UDB 3D model file. The component data must contain at least one skeleton data and component center coordinates. Skeleton data includes the vertex coordinates, normal coordinates, and material map coordinates of model components; The component data processing module is used for component data processing: processing the construction data obtained in step S1, including transforming the center coordinates of each component, and obtaining global coordinates of the normal vector and global coordinates of the model vertices; The aforementioned component center coordinate processing refers to the provision of a center coordinate for each component in the UDB data structure. Therefore, when performing coordinate transformation, it is necessary to transform the coordinates to the target measurement coordinate system and obtain the transformation center point. ; The acquisition of various global coordinates for each component refers to the acquisition of the vertex global coordinates of the UDB model. The data is obtained through a series of transformations, namely vertex coordinates. Center coordinates The transformation matrix R satisfies the following relationship: ; The global coordinate transformation module is used for global coordinate transformation and to obtain the target's global coordinates. And perform model component data reconstruction, including transformation matrix reconstruction and model geometric information reconstruction; Transformation matrix reconstruction: The transformation matrix of the reconstructed model component is replaced by the identity matrix. That is, R d satisfy: Model geometric information reconstruction includes normal vector coordinate reconstruction and model vertex coordinate reconstruction. The process of normal vector coordinate reconstruction and model vertex coordinate reconstruction is exactly the same. Using model vertex coordinates Refactoring, satisfying: ; The model component and dataset reconstruction module is used to reconstruct the model data based on the calculation results of the obtained model data, including the component center coordinates, transformation matrix, and reconstructed components of related skeleton data, and then transfer component attributes and reconstruct the dataset. Among them, transferring component attributes means that, according to the UDB format model, each component corresponds to one attribute information. Therefore, when constructing a new component, the corresponding attribute information must also be transferred to ensure the integrity of the BIM component. Reconstructing a dataset refers to the process of reconstructing a dataset by mapping multiple component data and their attributes according to UDB format requirements. The dataset output module is used to assign a new coordinate system to the reconstructed dataset, create a new dataset file under the current model data, and output the resulting dataset, the new coordinate system, and the model.

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