Multi-dimensional parameterized city information model construction method and system and computer device

Abstract

The application belongs to the technical field of city modeling, and is a multi-dimensional parameterized city information model construction method, system and device. The method comprises the following steps: constructing a geometric data structure and an entity semantic-oriented basic model library; constructing a parameter demodulator, which is used for extracting entity positions and construction parameters from an entity or a group of entities, and converting the extracted entity positions and construction parameters into parameter information supporting modeling of other entities; according to the composition logic of a modeling scene, hierarchically and gradually completing construction of the scene; constructing a framework object and a sub-object of the scene, and establishing a topological relationship and a correlation relationship between a parent object / brother object and the sub-object; and finding a corresponding model of the sub-object from the basic model library to perform parameterized modeling. The application accurately expresses spatial positions, shape placeholders and spatial correlations of entities, realizes parameterized conversion and establishment of the entities, enables the entities to have more accurate topological relationship definitions, and improves modeling speed.

Description

Technical Field

[0001] This invention belongs to the field of urban modeling technology, specifically relating to a method, system, and computer equipment for constructing a multidimensional parametric urban information model. Background Technology

[0002] City Information Modeling (CIM) is an emerging technology and a hot application and research frontier in the field of digital cities / smart cities. It is a digital platform and technology that evolves from Building Information Modeling (BIM) to the city level. The integration of BIM and GIS has broad application needs and is the foundation for refined and intelligent urban management. Both have value and necessity in terms of data structure and application. However, they have independent modeling methods and data standards, and there are significant differences in geometry and semantic information. For example, the 3D GIS standard CityGML uses surfaces to represent geometric information, while the IFC standard in the BIM field uses entities. The integration of BIM and GIS is one of the key technologies of CIM technology and platforms, and achieving integrated 3D modeling of BIM and GIS is a fundamental solution.

[0003] Traditional 3D modeling techniques based on surface representation are generally used to represent the basic appearance features of a city and can adapt to surface models of any shape; however, they also have many drawbacks, including a lack of entity semantics, difficulty in expressing topological relationships, and difficulty in describing the internal information of objects.

[0004] BIM modeling technology can supplement the shortcomings of traditional 3D modeling in these aspects, and it is widely used in various construction engineering fields such as architecture and bridges. Each component in a BIM model is a composite model with parameters and behavioral relationships, composed of numerous features. However, current BIM modeling technology still focuses more on the modeling parameters of the components themselves, without much consideration for the parametric linkage from the perspective of the relationships between components. Therefore, it has the following shortcomings: 1) BIM standards, such as the IFC standard, are numerous, have complex relationships, high learning costs, and low efficiency; topological relationships become virtual objects, making conversions prone to loss; 2) BIM modeling technology provides functions such as lofting and elevation to help users reduce repetitive modeling and achieve accurate positioning, but it is far from achieving intelligent, batch, and rapid modeling; 3) Based on secondary development, professional plug-in modules can be provided, but each function often has a narrow scope, requiring specialized knowledge and multi-tool linkage; 4) When the design scheme changes, multiple modifications and integrations are required; 5) BIM modeling products are often modeled separately by multiple disciplines, and then integrated after each discipline is built, which often easily leads to component conflicts. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a method, system, and computer device for constructing a multidimensional parametric urban information model. Through the digital representation of complex two-dimensional and three-dimensional entities and spaces, it accurately expresses the spatial location, morphological occupancy, and spatial relationships of CIM entities, realizing the parametric transformation and establishment of CIM entities. This enables more accurate topological relationship definitions between entities, allowing for linked updates, automatic updates, and complete updates of CIM scenes, thereby improving modeling speed.

[0006] The method of the present invention is implemented through the following technical solution: a method for constructing a multidimensional parametric urban information model, comprising the following steps:

[0007] Construct geometric data structures, the geometric objects of which include points, lines, surfaces, and spatial volumes;

[0008] Build a basic model library oriented towards entity semantics;

[0009] Construct a parameter demodulator to extract entity location and construction parameters from an entity or a group of entities, and convert the extracted entity location and construction parameters into parameter information that supports modeling other entities;

[0010] Based on the composition logic of the modeling scene, the scene is constructed step by step in a hierarchical manner; the constructed scene is a collection of spatial objects, and the inclusion and bearing relationships of entities are expressed in a tree structure; spatial objects include frame objects, entities, and rule entity groups;

[0011] The framework object for constructing the scene;

[0012] Construct sub-objects of the framework object, and establish topological relationships between parent and child objects, child and sibling objects, related objects and child objects, and associations between parent and child objects and child and sibling objects by utilizing the topological relationships between the child objects and existing entity objects or by relying on the parameter demodulator.

[0013] Determine if there is a space conflict between the child object and the rule entity group; if there is a space conflict between the child object and the rule entity group, the rule entity group will be automatically split according to the space of the child object.

[0014] Find the corresponding model of the sub-object from the basic model library and perform parametric modeling.

[0015] In a preferred embodiment, the constructed parameter demodulator includes an input module, an output module, and a calculation module, wherein the input module is used to obtain input parameters; the calculation module calculates the parameters input by the input module to obtain output parameters; and the output module provides the output parameters calculated by the calculation module for use by other entities.

[0016] More preferably, the parameters are parameters for constructing the geometric model, including numerical values, strings, geometric data, and data structures;

[0017] The input parameters of the input module include constant values, parameters of the entity object, and output parameters of other demodulators.

[0018] The output parameters of the output module are numeric types that can be directly used by other entity objects;

[0019] Based on the algorithm implementation technology of the computing module, parameter demodulators are divided into numerical parameter demodulators, geometric topology parameter demodulators, and parameter extraction parameter demodulators.

[0020] The numerical values ​​of the numerical parameter demodulator include constant values, programmatically calculated values, sequence arrays, and reduced-dimensional values.

[0021] The geometric topology class parameter demodulator performs spatial topology operations on the geometry, including:

[0022] A linear geometric decomposer divides a topological line into several sub-segments or location points;

[0023] A planar geometry decomposer divides a topological surface into several topological lines or location points;

[0024] A spatial volume geometry decomposer that divides a topological space volume into several topological surfaces, topological lines, or location points;

[0025] Spatial buffer unit buffers linear, planar, and spatial volumes according to a preset distance or image range to obtain new topological geometry;

[0026] The bearing surface extraction unit establishes a bearing surface for an object and uses the bearing surface as the attachment surface;

[0027] The cross-section analysis unit extracts the projected cross-section of a spatial body on a certain plane, and obtains a set of line segments;

[0028] Topological intersection elements are used to calculate the intersection points of topological geometry.

[0029] The parameter extraction demodulator is used to collect and summarize several parameters. The parameter extraction methods include:

[0030] Parameter transfer: Extract a parameter from the first entity and output it to the second entity;

[0031] Location collection involves extracting location parameters of multiple entities according to search rules.

[0032] Extract key nodes by marking and extracting key location points from the topological space to generate new topological geometric data.

[0033] In a preferred embodiment, the constructed scene achieves the following functional characteristics through the inclusion and carrying relationships of entities:

[0034] The ability to obtain any spatial object and search for the corresponding spatial entity by its name, type, or ID;

[0035] Obtain the organizational relationships of the scene, which include the child objects of the entity and the parent objects of the entity;

[0036] Obtain all entity attributes for each entity, including construction geometry parameters, position, and bounding box;

[0037] Set the attributes and parameters of any entity in the scene.

[0038] In a preferred embodiment, the entity represents a real-world object and has a three-dimensional model representation.

[0039] The framework object represents a carrier in space, has topological characteristics, and manages several sub-objects;

[0040] The rule entity group is a virtual management unit that contains several entities and provides specific locations, orientations and other modeling parameters for the entities; the rule entity group dynamically maintains the number and space occupancy of the child objects included in the parent object.

[0041] In a preferred embodiment, the sub-objects of the construction framework object include:

[0042] Obtain the geometric and attribute data of the child objects of the frame object;

[0043] If the child object and the existing entity object can pass parameters, then a corresponding parameter demodulator is created according to the parameter passing implementation logic. The input of the parameter demodulator is associated with the existing entity object from which the parameters need to be extracted, and the output of the parameter demodulator is associated with the current child object, thereby passing the geometric parameters of the associated object to the current child object; otherwise, no processing is performed, and the default containment relationship between the parent object and the child object is retained.

[0044] By creating modeling relationships, constraint relationships, and business relationships, the associations between parent objects and child objects, and between child objects and sibling objects are established. Among them, modeling relationships include opening relationships, constraint relationships include containment relationships, connection relationships, covering relationships, and projection relationships, and business relationships include link relationships.

[0045] More preferably, if multiple child objects are ordered fillings in the space of the parent object, then a rule entity group is first constructed, which manages several entities, and the number and space occupancy of the multiple child objects contained in the parent object are dynamically maintained through the rule entity group.

[0046] Preferably, the construction method further includes: updating the scene model based on changes in the parameters of the framework object and its sub-objects; the updating of the scene model includes:

[0047] If the parameters of the frame object change, the child objects are notified to recalculate the modeling parameters and obtain new space occupancy information. The frame object determines whether there is a collision with the child objects. If there is no collision, the parameters are allowed to be updated, and the changes in parameters are applied to update the model of the frame object and its child objects. Otherwise, a conflict is reported or the corresponding parameters are not adjusted.

[0048] If a child object is moved or its modeling parameters are adjusted, the new space occupancy is calculated first, and the parent object is notified to calculate whether there is a collision between the child objects. If there is no collision, the corresponding adjustment is made. If there is a collision, the conflict is reported or the corresponding parameters are not adjusted.

[0049] The system of the present invention is implemented through the following technical solution: a multi-dimensional parametric urban information model construction system, comprising the following modules:

[0050] The data structure construction module is used to construct geometric data structures, and the geometric objects of the constructed geometric data structures include points, lines, surfaces, and spatial volumes;

[0051] The basic model library building module is used to build a basic model library oriented towards entity semantics.

[0052] The parameter demodulator building module is used to build a parameter demodulator, which is used to extract entity location and construction parameters from an entity or a group of entities, and convert the extracted entity location and construction parameters into parameter information that supports modeling other entities.

[0053] The scene construction module is used to construct the scene step by step in a hierarchical manner according to the composition logic of the modeling scene. The constructed scene is a collection of spatial objects, and the inclusion and carrying relationships of entities are expressed in a tree structure. Spatial objects include frame objects, entities, and rule entity groups.

[0054] The object construction module is used to construct the framework object of the scene; and to construct the sub-objects of the framework object. It uses the topological relationship between the sub-object and the existing entity object or based on the parameter demodulator to establish the topological relationship between the parent object and the child object, the topological relationship between the child object and the sibling object, the topological relationship between the associated object and the child object, and the association relationship between the parent object and the child object, and between the child object and the sibling object.

[0055] The parameterization module is used to find the corresponding model of the sub-object from the basic model library and perform parameterized modeling.

[0056] The object construction module is also used to determine whether there is a conflict between the space occupancy of the sub-object and the rule entity group; if there is a conflict between the space occupancy of the sub-object and the rule entity group, the rule entity group is automatically divided according to the space occupancy of the sub-object.

[0057] The computer device of the present invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the multidimensional parametric urban information model construction method of the present invention.

[0058] Compared with the prior art, the present invention has the following advantages:

[0059] 1. By digitally representing complex two-dimensional and three-dimensional entities and spaces, the spatial location, morphological occupancy, and spatial relationships of CIM entities are accurately expressed. This enables the parametric transformation and establishment of CIM entities, allowing for more accurate topological relationship definitions between entities. It also enables parameter-based CIM updates, giving CIM scenes the ability to be driven by geometric parameters and topological parameters.

[0060] 2. It can effectively organize and manage entities in a CIM scenario in a multi-level and multi-dimensional manner, and supports index queries based on the hierarchical relationship of the scenario, entity attributes, and entity association relationships.

[0061] 3. The constructed model contains rich relationships, and the framework objects and rule entity groups have capabilities such as sub-object management and parameter passing, thus greatly improving multi-entity management capabilities. The parameter passing and sharing mechanism further enables linked updates, automatic updates, and complete updates of the CIM scene. Through the parameter demodulator, modeling parameters can be obtained from associated entities, reducing manual interaction and thus improving modeling speed. General modeling techniques only consider linked updates of local scenes; after adjustments to the modeling scheme, the scope of scene updates becomes large, resulting in a lot of repetitive work.

[0062] 4. Compared with general modeling techniques, the modeling results of this invention not only have a three-dimensional model, but also have rich semantic information, retain the correlation during modeling, effectively realize the integration of BIM and GIS, and provide data support for subsequent CIM applications.

[0063] 5. This invention provides a business process for reading, calculating, and using parameters from entities, greatly reducing the requirements for users to handle modeling parameters; this modeling method using relationships is also easier to understand and simpler to operate. General modeling techniques focus more on the parameterization of specific components, lacking parameter transfer between components, resulting in complex operations. Attached Figure Description

[0064] Figure 1 This is a flowchart of the method for constructing a multidimensional parametric city information model in an embodiment of the present invention.

[0065] Figure 2 This is a schematic diagram of the composition logic of the parameter demodulator in an embodiment of the present invention;

[0066] Figure 3 This is a schematic diagram of the collaborative mechanism between the scene and the parameter demodulator in an embodiment of the present invention;

[0067] Figure 4 This is a schematic diagram of the city information model update in an embodiment of the present invention. Detailed Implementation

[0068] This invention relates to a parametric representation and dynamic update method for two- and three-dimensional entities and their spatial topological relationships, and to a method and system for constructing a multidimensional parametric urban information model. The invention will be further described below with reference to the accompanying drawings and embodiments, but the implementation of the invention is not limited thereto.

[0069] Example 1

[0070] In the real world, various entities have strong interrelationships; they are interdependent, mutually supportive, and even share the same or similar parameters. For example, utility tunnels and their supports and pipelines share the same orientation, and room walls and their internal pipelines and furniture have inclusion and dependency relationships. If these parameters can be effectively reused, the tedious, complex, and repetitive work in facility layout, space management, and scene component updates can be significantly reduced.

[0071] Therefore, this embodiment takes a two-pronged approach: first, defining the digital representation of complex two- and three-dimensional entities and spaces; and second, implementing parametric modeling and establishing a multi-dimensional parametric urban information model construction method. Specifically, it includes defining an integrated two- and three-dimensional geometric data structure, adopting a top-down modeling strategy, and forming a multi-dimensional association and linked update modeling mechanism by passing component modeling parameters. This significantly improves modeling efficiency, offers ease of use and intuitiveness, enables scene linkage and automatic updates, and the modeling results possess good semantic features.

[0072] This embodiment establishes a flexible method for constructing urban information models based on the relationships between entities, allowing for the transmission of entity modeling parameters. This method primarily involves establishing a hierarchical classification and management mechanism for entities and a multi-level message passing mechanism based on the scene, as well as achieving parameter information sharing among entities based on parameter demodulators. This enables accurate, rapid, and self-resolving entity spatial occupancy and quick responsive scene updates. Its core components include constructing a unified 2D and 3D geometric data structure, a parameterized CIM basic model library, and various types of parameter demodulators.

[0073] Specifically, such as Figure 1 As shown, the multidimensional parametric urban information model construction method in this embodiment includes the following steps:

[0074] S1. Construct a two-dimensional and three-dimensional integrated geometric data structure, which includes geometric objects such as points, lines, surfaces, and spatial volumes.

[0075] S2. Construct a CIM basic model library oriented towards entity semantics. The constructed CIM basic model library is a CIM entity template library, whose 3D model geometry is generated using CSG modeling technology driven by construction geometric parameters.

[0076] S3. Construct a set of parameter demodulators to extract entity positions and construction parameters from an entity or a group of entities, and convert the extracted entity positions and construction parameters into parameter information that supports modeling other entities through numerical calculation, geometric calculation and other methods.

[0077] The constructed parameter demodulator includes an input module, an output module, and a calculation module. The input module obtains input parameters from sources including associated entities. The calculation module calculates the parameters input by the input module to obtain output parameters. The output module provides the calculated output parameters for use by other entities. The number of input and output parameters of the parameter demodulator is determined by the algorithm module. These parameters are primarily for constructing the geometric model and can be numerical values, strings, geometric data, or complex data structures, such as a data structure composed of handles to other parameter demodulators and names of output attributes. The composition logic of the parameter demodulator is described below. Figure 2 .

[0078] In this embodiment, the input module of the parameter demodulator includes various inputs, the specific types of which are as follows:

[0079] 1) Constant value: can be a specific value entered by the user.

[0080] 2) Entity object parameters: Entity objects can be searched within the scene using keywords such as name, type, and ID. Since entity object parameters are public, they can be obtained through APIs and interfaces.

[0081] 3) Output parameters of other parameter demodulators: obtained from the output parameters of other parameter demodulators.

[0082] Taking the parameters for building a 5-meter wall as an example, as shown in Table 1:

[0083] Table 1

[0084]

[0085] The output module of the parameter demodulator can output one or more parameters. Output parameters are generally numeric and can be directly used by other entity objects. They can also be obtained through an interface (interface name: getOutputByName(String outPropertyName)) for dynamic updates.

[0086] The computation module of the parameter demodulator performs calculations according to a preset algorithm. Based on the algorithm implementation technology of the computation module, parameter demodulators can be classified into numerical parameter demodulators, geometric topology parameter demodulators, and parameter extraction parameter demodulators.

[0087] The calculation module of the numerical parameter demodulator is based on numerical values, which include the following types:

[0088] 1) Constant values. Provide fixed parameters for situations such as elevation and axis.

[0089] 2) Programmatic numerical calculation. Provides numerical calculation methods, such as trigonometric functions.

[0090] 3) Sequence array. Provides random values ​​and an array arranged according to a predetermined rule.

[0091] 4) Dimensionality reduction values. Extracting dimensionality-reduced values ​​from multidimensional values, such as extracting the Z coordinate from a point in three-dimensional space.

[0092] 5) Other types. For example, providing expressions that combine proportions and numbers.

[0093] In this embodiment, the geometric topology parameter demodulator performs spatial topology operations on geometric objects such as points, lines, surfaces, and solids. The spatial topology operations include the following types:

[0094] 1) Linear geometric decomposer. It can divide a topological line into several sub-segments or position points.

[0095] 2) Planar geometry decomposer. It can divide a topological surface into several topological lines or position points.

[0096] 3) Spatial volume geometry decomposer. It can divide a topological spatial volume into several topological surfaces, topological lines, or position points.

[0097] 4) Spatial buffer unit. It can buffer linear, planar, and spatial volumes according to a preset distance or image range to obtain a new topological geometry.

[0098] 5) Load-bearing surface extraction unit. Create a load-bearing surface for an object, which can be used as the attachment surface.

[0099] 6) Cross-sectional analysis unit. Extract the projected cross-section of a spatial volume on a certain plane to obtain a set of line segments.

[0100] 7) Topological Intersection Element. Calculate the intersection points of the topological geometry based on the topological geometry of the line segments.

[0101] 8) Other topology algorithms.

[0102] In this embodiment, the parameter extraction demodulator is used to collect and summarize several parameters. The parameter extraction methods include the following types:

[0103] 1) Parameter transfer. Extract a parameter from the first entity A and output it to the second entity B.

[0104] 2) Location collection. Extract location parameters of multiple entities according to search rules (such as by entity type).

[0105] 3) Extract key nodes. Key locations in the topological space, such as topological lines, topological surfaces, and topological points, can be marked and extracted to generate new topological geometric data.

[0106] 4) Other parameter extraction algorithms.

[0107] S4. Based on the composition logic of the modeling scene, the scene is constructed layer by layer and level by level. The constructed scene includes a management framework composed of several spatial objects, which is a collection of spatial objects; among them, spatial objects include frame objects, entities, rule entity groups, etc.

[0108] The scene constructed in this step uses a tree structure to express the containment and carrying relationships of entities, and achieves the following functional characteristics through the containment and carrying relationships of entities:

[0109] 1) The ability to obtain any spatial object. For example, searching for the corresponding spatial entity by its name (SelectByName), type (SelectByType), or ID (SelectByID).

[0110] 2) Obtain the organizational relationships of the scene, which include the child objects of the entity, the parent objects of the entity, etc.

[0111] 3) Obtain all entity attributes for each entity, including construction geometry parameters, position, and bounding box.

[0112] 4) Set the attributes, parameters, and other information of any entity in the scene.

[0113] In the scenario constructed in this step, each tree node in the tree structure corresponds to a SpaceObject. SpaceObjects come in three forms: frame objects, rule entity groups, and entities, all of which possess spatial location and spatial extent. Their basic attribute definitions are shown in Table 2.

[0114] Table 2

[0115]

[0116]

[0117] Among them, an entity represents a real-world object, has a three-dimensional model representation, inherits from spatial objects, and extends the attributes shown in Table 3.

[0118] Table 3

[0119]

[0120] A FrameObject represents a spatial entity with certain topological characteristics (such as closure and topological stability), and it manages several sub-objects. A FrameObject can be a virtual entity (such as a room) or a concrete 3D model representation; it inherits the definition of an entity and extends the attributes shown in Table 4.

[0121] Table 4

[0122] Children (subset of objects) SpaceObject[] It can contain several sub-objects

[0123] A RuledEntityGroup is a virtual management unit that contains several entities and provides these entities with specific locations, orientations, and other modeling parameters. It is generally used for managing entities arranged according to certain rules, such as pipelines that have topological relationships and are segmented. The construction geometry parameters of a RuledEntityGroup are often polylines, polygons, or spatial volumes, rather than a single spatial point. A RuledEntityGroup can dynamically maintain the number and spatial occupancy of its parent object's child objects, inheriting the definitions of spatial objects and extending the attributes shown in Table 5.

[0124] Table 5

[0125] Parameter demodulator ID Integer Points to a parameter demodulator Children (subset of objects) SpaceObject[] It can contain several sub-objects

[0126] S5. Construct the scene's frame object. If the frame object is not a virtual object, then create a 3D model of the frame object; if the frame object is a virtual object, then add nodes to the scene's tree structure (also called the scene tree).

[0127] Depending on the complexity of the scene, a scene can contain one or more frame objects. The geometric data and attribute data of the frame objects can be obtained through data parsing methods such as CAD and SHP, or user drawing. The geometric model is found from the basic model library and parametrically modeled.

[0128] S6. Construct child objects of the framework object, establish topological relationships between parent and child objects, child and sibling objects, related objects and child objects, as well as the relationships between parent and child objects and between child and sibling objects, and add them to the corresponding nodes in the scene tree.

[0129] Each constructed frame object and its child objects are space objects. A child object can be a concrete entity object, meaning it no longer contains other child objects; or it can be a frame object (i.e., a parent object), meaning it still contains child objects. The construction process of a child object includes the following steps:

[0130] S61. Obtain the geometric and attribute data of the sub-objects of the framework object through data parsing methods such as CAD and SHP or user drawing.

[0131] S62. If the sub-object and the existing entity object can pass parameters, that is, the construction geometric parameters of the sub-object can be converted from the parameters of the existing entity object through geometric operations, numerical calculations, etc., then a parameter demodulator is created, the input of the parameter demodulator is associated with the object whose parameters need to be extracted, and the output of the parameter demodulator is associated with the current sub-object (i.e., this sub-object), thereby realizing the passing of the geometric parameters of the associated object (i.e., the associated existing entity object) to the current sub-object; otherwise, no processing is performed, and the parent object and the sub-object retain the default containment relationship.

[0132] Each sub-entity (i.e., sub-object) in a rule entity group can be provided with independent position, orientation, and other parameters by the parameter demodulator.

[0133] The collaborative mechanism between the scene and the parameter demodulator, such as Figure 3 As shown. The parameter demodulator can obtain parameters of any spatial object in the scene; it can also set parameters of any spatial object in the scene. The spatial objects include each frame object and its sub-objects in the scene.

[0134] S63. Establish relationships between parent and child objects, and between child and sibling objects, by creating modeling relationships, constraint relationships, and business relationships. Among them, modeling relationships, such as opening relationships, are used to trigger the reconstruction of the target 3D model; constraint relationships are used to control the topological relationships that objects must satisfy; and business relationships are used to clarify the ownership and reference relationships with internal resources.

[0135] Among them, modeling relationships include opening relationships, constraint relationships include containment relationships, connection relationships, coverage relationships and projection relationships, and business relationship relationships include link relationships.

[0136] When establishing relationships between parent and child objects, and between child and sibling objects, it is necessary to analyze and extract the spatial geometric connections between them. For example, if the geometric axis data of the parent and child objects (such as the axis of a wall being the center line at the bottom of the wall) are a set of parallel line segments, then a disjoint relationship can be established. Similarly, a child object can also analyze its spatial geometric connections with its sibling objects to establish a relationship between them.

[0137] In this step, if multiple child objects are ordered fillings of the parent object's space, a rule entity group can be constructed first, and the rule entity group can manage several entities. The number and space occupancy of the multiple child entities contained in the parent object can be dynamically maintained through the rule entity group.

[0138] Relationships are an important part of parametric modeling, enabling coupling between entities. Table 6 shows a breakdown and explanation of various relationships.

[0139] Table 6

[0140]

[0141] In this embodiment, the relationship is stored in the "Relationship" field of the entity, using JSON or other similar methods. Different relationship storage structures may vary, but all include the relationship type, relationship name, target object ID, and other parameter information.

[0142] In a preferred embodiment, the relationships in the modeling process can be created automatically or added proactively based on the actual situation.

[0143] Automatically created relationships include containment relationships and connection relationships. Containment relationships are embedded in the scene's hierarchical structure, while connection relationships are embedded in the parameter demodulator.

[0144] Actively added relationships include opening relationships, covering relationships, projection relationships, and linking relationships. These relationships require modelers to fill in the information based on the actual situation between entities. For example, a covering relationship is the relationship between this object and other objects; this is an active setting. Of course, intelligent semantic analysis can reduce the manual entry of these relationships, but it is still a human perception of entity relationships.

[0145] Relationships can be used in the modeling process and in subsequent applications. Automatically created relationships are maintained by the modeling scene, while actively added relationships can be used for scene modeling and updates. For example, opening relationships can affect the model construction process of the parent object, impacting the model's shape. The overlap relationship between the current object and related objects can be verified through spatial geometric calculations; if the condition is not met, a warning message will be output.

[0146] S7. During the construction of sub-objects of the framework object, determine whether there is a conflict between the space occupied by the sub-object and the regular entity group. If there is a conflict between the space occupied by the sub-object and the regular entity group, the regular entity group is automatically divided according to the space occupied by the sub-object. Specifically, linear regular entity groups are divided into multiple segments, planar regular entity groups can be opened, and spatial volume regular entity groups occupy part of the space.

[0147] S8. Find the corresponding model of the sub-object from the CIM basic model library in step S2 and perform parametric modeling.

[0148] S9. Repeat steps S6-S8 above, continuously adding child objects contained in the parent object to the scene until no more child objects need to be created. The scene can use multiple top-level framework objects, containing all entities to be modeled. The final result is a multi-layered tree structure scene based on parent-child object relationships. The leaf nodes of this scene tree are independent entities that do not contain other spatial objects.

[0149] S10. After constructing the complete scene, update the scene model based on the parameter changes of the framework object and its sub-objects, such as... Figure 4 As shown. Specifically, it includes the following situations:

[0150] S101. If the parameters of the frame object change, it informs the child objects to recalculate the modeling parameters and obtain new space occupancy information. The frame object determines whether the child objects can be updated, i.e., whether there is a collision. If there is no collision, it allows the response parameters and applies the parameter changes to update the models of the frame object and its child objects; otherwise, it reports a conflict or does not adjust the corresponding parameters. The child objects also pass parameter change information to themselves.

[0151] S102. If a child object is moved or its modeling parameters are adjusted, first calculate the new space occupancy and notify the parent object to calculate whether there is a collision between child objects. If there is no collision, make the corresponding adjustments; if there is a collision, inform the parent object of the conflict or do not adjust the corresponding parameters.

[0152] S11. Generate model files and store the modeling process. Read the model of each entity in the scene and generate a 3D model file or a BIM model file. The modeling process includes the scene's organizational relationships and the content of all parameter demodulator nodes.

[0153] Example 2

[0154] Based on the same inventive concept as Embodiment 1, this embodiment provides a multidimensional parametric urban information model construction system, including the following modules:

[0155] The data structure construction module is used to construct geometric data structures, and the geometric objects of the constructed geometric data structures include points, lines, surfaces, and spatial volumes;

[0156] The basic model library building module is used to build a basic model library oriented towards entity semantics.

[0157] The parameter demodulator building module is used to build a parameter demodulator, which is used to extract entity location and construction parameters from an entity or a group of entities, and convert the extracted entity location and construction parameters into parameter information that supports modeling other entities.

[0158] The scene construction module is used to construct the scene step by step in a hierarchical manner according to the composition logic of the modeling scene. The constructed scene is a collection of spatial objects, and the inclusion and carrying relationships of entities are expressed in a tree structure. Spatial objects include frame objects, entities, and rule entity groups.

[0159] The object construction module is used to construct the framework object of the scene; and to construct the sub-objects of the framework object. It uses the topological relationship between the sub-object and the existing entity object or based on the parameter demodulator to establish the topological relationship between the parent object and the child object, the topological relationship between the child object and the sibling object, the topological relationship between the associated object and the child object, and the association relationship between the parent object and the child object, and the association relationship between the child object and the sibling object; and realizes the coupling between entities through the association relationship.

[0160] The parameterization module is used to find the corresponding model of the sub-object from the basic model library and perform parameterized modeling.

[0161] The scene update module is used to update the scene model based on changes in the parameters of the framework object and its sub-objects.

[0162] The object construction module is also used to determine whether there is a conflict between the space occupied by the child object and the rule entity group; if there is a conflict between the space occupied by the child object and the rule entity group, the space occupied by the child object is automatically divided by the rule entity group.

[0163] The modules described above in this embodiment are used to execute the steps of embodiment 1, and the detailed execution process can be found in embodiment 1, which will not be repeated here.

[0164] This embodiment also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the multidimensional parameterized urban information model construction method of Embodiment 1.

[0165] The above description is only a preferred embodiment of the present invention, but the scope of protection of the invention patent is not limited thereto. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the scope of protection of the present invention.

Claims

1. A method for constructing a multidimensional parametric urban information model, characterized in that, Includes the following steps: Construct geometric data structures, the geometric objects of which include points, lines, surfaces, and spatial volumes; Construct a CIM basic model library oriented towards entity semantics; the CIM basic model library is a CIM entity template library, whose 3D model geometry is generated by CSG modeling technology driven by construction geometric parameters; Construct a parameter demodulator to extract entity location and construction parameters from an entity or a group of entities, and convert the extracted entity location and construction parameters into parameter information that supports modeling other entities; Based on the composition logic of the modeling scene, the scene is constructed step by step in a layered and hierarchical manner. The constructed scene is a collection of spatial objects, and the inclusion and carrying relationships of entities are expressed in a tree structure. Spatial objects include frame objects, entities, and rule entity groups. The frame object represents a carrier in space, has topological features, and manages several sub-objects. The frame object can be a virtual object or have a specific 3D model expression form. The rule entity group is a virtual management unit, containing several entities, and providing specific positions, orientations, and other modeling parameters for the entities. The rule entity group dynamically maintains the number and spatial occupancy of the several sub-objects included in the parent object. Construct the scene's frame object; if the frame object is not a virtual object, create a 3D model of the frame object; if the frame object is a virtual object, add nodes to the scene's tree structure. Construct sub-objects of the framework object, and establish topological relationships between parent and child objects, child and sibling objects, and associated objects and child objects, as well as association relationships between parent and child objects and child and sibling objects, by utilizing the topological relationships between sub-objects and existing entity objects or based on the parameter demodulator, and add them to the corresponding nodes in the scene's tree structure; associated objects are associated existing entity objects; coupling between entities is achieved through association relationships; Determine if there is a space conflict between the child object and the rule entity group; if there is a space conflict between the child object and the rule entity group, the rule entity group will be automatically split according to the space of the child object. Find the corresponding model of the sub-object from the CIM basic model library and perform parametric modeling; The constructed parameter demodulator includes an input module, an output module, and a calculation module, wherein the input module is used to obtain input parameters; The calculation module calculates the parameters input by the input module and obtains the output parameters; The output module provides the output parameters calculated by the calculation module for use by other entities; The sub-objects of the construction framework object include: Obtain the geometric and attribute data of the child objects of the frame object; If the child object and the existing entity object can pass parameters, then a corresponding parameter demodulator is created according to the parameter passing implementation logic. The input of the parameter demodulator is associated with the existing entity object from which the parameters need to be extracted, and the output of the parameter demodulator is associated with the current child object, thereby passing the geometric parameters of the associated object to the current child object; otherwise, no processing is performed, and the default containment relationship between the parent object and the child object is retained. By creating modeling relationships, constraint relationships, and business relationships, the associations between parent objects and child objects, and between child objects and sibling objects are established. Among them, modeling relationships include opening relationships, constraint relationships include containment relationships, connection relationships, covering relationships, and projection relationships, and business relationships include link relationships.

2. The method for constructing a multidimensional parametric urban information model according to claim 1, characterized in that, The parameters are those used to construct the geometric model, including numerical values, strings, geometric data, and data structures; The input parameters of the input module include constant values, parameters of the entity object, and output parameters of other demodulators. The output parameters of the output module are numeric types that can be directly used by other entity objects; Based on the algorithm implementation technology of the computing module, parameter demodulators are divided into numerical parameter demodulators, geometric topology parameter demodulators, and parameter extraction parameter demodulators. The numerical values ​​of the numerical parameter demodulator include constant values, programmatically calculated values, sequence arrays, and reduced-dimensional values. The geometric topology class parameter demodulator performs spatial topology operations on the geometry, including: A linear geometric decomposer divides a topological line into several sub-segments or location points; A planar geometry decomposer divides a topological surface into several topological lines or location points; A spatial volume geometry decomposer that divides a topological space volume into several topological surfaces, topological lines, or location points; Spatial buffer unit buffers linear, planar, and spatial volumes according to a preset distance or image range to obtain new topological geometry; The bearing surface extraction unit establishes a bearing surface for an object and uses the bearing surface as the attachment surface; The cross-section analysis unit extracts the projected cross-section of a spatial body on a certain plane, and obtains a set of line segments; Topological intersection elements are used to calculate the intersection points of topological geometry. The parameter extraction demodulator is used to collect and summarize several parameters. The parameter extraction methods include: Parameter transfer: Extract a parameter from the first entity and output it to the second entity; Location collection involves extracting location parameters of multiple entities according to search rules. Extract key nodes by marking and extracting key location points from the topological space to generate new topological geometric data.

3. The method for constructing a multidimensional parametric urban information model according to claim 1, characterized in that, The constructed scene achieves the following functional characteristics through the inclusion and carrying relationships of entities: The ability to obtain any spatial object and search for the corresponding spatial entity by its name, type, or ID; Obtain the organizational relationships of the scene, which include the child objects of the entity and the parent objects of the entity; Obtain all entity attributes for each entity, including construction geometry parameters, position, and bounding box; Set the attributes and parameters of any entity in the scene.

4. The method for constructing a multidimensional parametric urban information model according to claim 1, characterized in that, The entity represents a real-world object and has a three-dimensional model representation.

5. The method for constructing a multidimensional parametric urban information model according to claim 1, characterized in that, If multiple child objects are ordered fillings of the parent object's space, then a rule entity group is first constructed. The rule entity group manages several entities and dynamically maintains the number and space occupancy of the multiple child objects contained in the parent object through the rule entity group.

6. The method for constructing a multidimensional parametric urban information model according to claim 1, characterized in that, The construction method further includes: updating the scene model based on changes in the parameters of the framework object and its sub-objects; the updating of the scene model includes: If the parameters of the frame object change, the child objects are notified to recalculate the modeling parameters and obtain new space occupancy information. The frame object determines whether there is a collision with the child objects. If there is no collision, the parameters are allowed to be updated, and the changes in parameters are applied to update the model of the frame object and its child objects. Otherwise, a conflict is reported or the corresponding parameters are not adjusted. If a child object is moved or its modeling parameters are adjusted, the new space occupancy is calculated first, and the parent object is notified to calculate whether there is a collision between the child objects. If there is no collision, the corresponding adjustment is made. If there is a collision, the conflict is reported or the corresponding parameters are not adjusted.

7. A multidimensional parametric urban information model construction system, characterized in that, Based on the construction method described in claim 1, the construction system includes the following modules: The data structure construction module is used to construct geometric data structures, and the geometry of the constructed geometric data structures includes points, lines, surfaces, and spatial volumes; the basic model library construction module is used to construct a CIM basic model library oriented towards entity semantics; the CIM basic model library is a CIM entity template library, and the geometry of its 3D model is generated using CSG modeling technology driven by the construction of geometric parameters; The parameter demodulator building module is used to build a parameter demodulator, which is used to extract entity location and construction parameters from an entity or a group of entities, and convert the extracted entity location and construction parameters into parameter information that supports modeling other entities. The scene construction module is used to construct the scene layer by layer and hierarchically according to the composition logic of the modeling scene. The constructed scene is a collection of spatial objects, and the inclusion and carrying relationships of entities are expressed in a tree structure. Spatial objects include frame objects, entities, and rule entity groups. The frame object represents a carrier in space, has topological features, and manages several sub-objects. The frame object can be a virtual object or have a specific 3D model expression form. The rule entity group is a virtual management unit, containing several entities, and providing specific positions, orientations, and other modeling parameters for the entities. The rule entity group dynamically maintains the number and spatial occupancy of the several sub-objects included in the parent object. The object construction module is used to construct the framework object of the scene; and to construct the child objects of the framework object. It uses the topological relationship between the child object and the existing entity object or according to the parameter demodulator to establish the topological relationship between the parent object and the child object, the topological relationship between the child object and the sibling object, the topological relationship between the associated object and the child object, and the association relationship between the parent object and the child object, and the association relationship between the child object and the sibling object, and adds them to the corresponding nodes of the scene's tree structure. The parameterization module is used to find the corresponding model of the sub-object from the CIM basic model library and perform parameterized modeling. The object construction module is also used to determine whether there is a conflict between the space occupancy of the sub-object and the rule entity group; if there is a conflict between the space occupancy of the sub-object and the rule entity group, the rule entity group is automatically divided according to the space occupancy of the sub-object.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method for constructing a multidimensional parametric urban information model as described in any one of claims 1-6.

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