Building layering and household-splitting three-dimensional model construction method based on house property layering and household-splitting graph

Abstract

The invention relates to a building layering and household-splitting three-dimensional model construction method based on a house property layering and household-splitting graph. The method comprises the following steps: preprocessing CAD data of a house property layering and household-splitting graph; on the basis of vectors in the CAD data, constructing a vector surface of each household of each floor of the real estate by adopting a left-turn algorithm; associating the auxiliary modeling data contained in the building table to the vector surface of each household of the corresponding layer based on the annotation information of the layer number points in the CAD data; the method comprises the following steps: calculating a spatial position relationship between each family name point and a vector surface of each family of each layer, and associating annotation information in each family name point to the vector surface of the corresponding family; on the basis of the space coordinates of the alignment points in the CAD data, the vector surfaces of all the layers are stacked together; and moving the vector surface of each layer to a corresponding elevation position, modeling, forming a building layering and household three-dimensional geometry, moving the building layering and household three-dimensional geometry to the real coordinates of the real estate under the earth surface projection coordinate system, and outputting a building layering and household three-dimensional model. And the modeling efficiency and quality are improved.

Description

Technical Field

[0001] This application relates to the field of 3D modeling technology, and particularly to a method for constructing a 3D model of building floor-by-floor and household-by-household based on real estate floor-by-floor and household-by-household maps. Background Art

[0002] The 3D model of building floor-by-floor and household-by-household is a 3D internal space data model of a building generated based on 2D real estate data such as real estate floor-by-floor and household-by-household maps and building lists, aiming to intuitively and vividly express the internal information of the building, and is an indispensable basic data unit in the urban information model data system. The current modeling methods mainly include: ① Manual modeling method, where modelers manually model based on 2D drawings with the help of 3D modeling software such as Autodesk Revit and 3ds Max; ② Extrusion modeling method, where in various GIS software, a 3D block model is constructed by extruding 2D vector data; ③ Automatic modeling method, where algorithms are used to automatically extract floor-by-floor and household-by-household vectors, identify floor and household objects, and quickly construct a 3D model of building floor-by-floor and household-by-household through alignment, extrusion, registration, etc.

[0003] Although the manual modeling method can construct a high-precision 3D model of floor-by-floor and household-by-household, it depends on professional modeling software and modelers, and has problems such as low efficiency and high costs. Although the extrusion modeling method can achieve rapid modeling, the modeling result is only a simple block form with low precision. The automatic modeling method is the current mainstream modeling method, and both the modeling efficiency and quality are at a relatively high level, but its modeling effect highly depends on the drawing quality and algorithm capabilities, and is mainly for specific fields with limited technical application scope. In addition, there are many difficulties in the utilization of current real estate floor-by-floor and household-by-household maps: ① CAD data is redundant, with a large amount of unnecessary information such as lines and annotations; ② There is no unified standard for the production of real estate household-by-household maps in each region, resulting in inconsistent element representation forms and uneven quality of floor-by-floor and household-by-household maps; ③ Real estate floor-by-floor and household-by-household maps are usually in a free coordinate system, and each floor is placed relative to each other, and each floor needs to be placed in the correct geographical coordinates; ④ The existing annotation information in real estate floor-by-floor and household-by-household maps cannot meet the modeling needs, such as the lack of floor height information and household room attribution information.

[0004] Therefore, the current efficiency and quality of constructing the 3D model of floor-by-floor and household-by-household are relatively low. Summary of the Invention

[0005] Based on this, it is necessary to provide a method for constructing a 3D model of building floor-by-floor and household-by-household based on real estate floor-by-floor and household-by-household maps, which can improve the efficiency and quality of constructing the 3D model of floor-by-floor and household-by-household for the above technical problems.

[0006] A method for constructing a 3D model of building floor-by-floor and household-by-household based on real estate floor-by-floor and household-by-household maps, the method includes:

[0007] S1, Data preprocessing: Preprocess the CAD data of the property's floor and household plan, store the annotation information and vector elements in the CAD data in separate layers, add annotation points and annotation frames to the CAD data, and create a building table and a registration table for the property that contain auxiliary modeling data. The annotation points include alignment points, registration points, household name points, and floor number points;

[0008] S2, Topological surface construction: Based on the vectors in the CAD data, use the left-turn algorithm to construct the vector surfaces of each household on each floor of the property;

[0009] S3, Map-attribute association: Based on the annotation information of the floor number points in the CAD data, associate the auxiliary modeling data contained in the building table to the vector surfaces of each household on the corresponding floor; by calculating the spatial position relationship between each household name point and the vector surfaces of each household on each floor, then associate the annotation information in each household name point to the vector surface of the corresponding household;

[0010] S4, Vertical alignment: Based on the spatial coordinates of the alignment points in the CAD data, stack the vector surfaces of each layer together;

[0011] S5, Floor and household division: Based on the vector surfaces of each layer and the auxiliary modeling data, supplement and improve the modeling data source through elevation calculation and cloning operations;

[0012] S6, 3D modeling: Move the vector surfaces of each layer to the corresponding elevation positions and perform stretching modeling to form a 3D geometric body of the property's floor and household division;

[0013] S7, Spatial registration: Based on the annotation points and the registration table in the CAD data, move the 3D geometric body of the property's floor and household division to the real coordinates of the property under the earth's surface projection coordinate system;

[0014] S8, Model output: Organize the 3D geometric body data of the property's floor and household division in the form of building, floor, and household, and output a 3D model of the property's floor and household division in IFC format.

[0015] In one of the embodiments, the preprocessing of the CAD data of the property's floor and household plan, storing the annotation information and vector elements in the CAD data in separate layers, adding annotation points and annotation frames to the CAD data, and creating a building table and a registration table for the property that contain auxiliary modeling data includes:

[0016] Use Autodesk CAD to preprocess the CAD data of the property's floor and household plan, store the annotation information and vector elements in the CAD data in separate layers, add annotation points and annotation frames to the CAD data, and create a building table and a registration table for the property that contain auxiliary modeling data.

[0017] In one embodiment, constructing the vector surface of each household of the property based on the vectors in the CAD data and using the left-turn algorithm includes:

[0018] Traverse all vector elements in the CAD data, introduce computational geometry algorithms to detect the intersection points of vector elements, and break at the intersections;

[0019] For vector elements with overlapping phenomena, only retain one of the vector elements;

[0020] Traverse all the retained vector elements, and use the left-turn algorithm to reconstruct the vector surface of each household on each floor of the property.

[0021] In one embodiment, associating the auxiliary modeling data included in the building table to the vector surface of each household on the corresponding floor based on the annotation information of the floor number points in the CAD data includes:

[0022] Match the annotation information of the floor number points in the CAD data with the field information in the building table to determine the matching annotation information and field information, and associate the entire row information of the field information in the auxiliary modeling data of the building table to the floor number point corresponding to the annotation information;

[0023] Calculate the spatial positions of each floor number point and each annotation box. Based on the spatial positions of each floor number point and each annotation box, use the ray method to determine the intersecting floor number points and annotation boxes, and associate the auxiliary modeling data associated with the floor number point to the annotation box;

[0024] Calculate the spatial positions of each annotation box and the vector surface of each household on each floor. Based on the spatial positions of each annotation box and the vector surface of each household on each floor, use the polygon intersection detection function to determine the intersecting annotation boxes and vector surfaces, and associate the auxiliary modeling data associated with the annotation box to the vector surface intersecting with it.

[0025] In one embodiment, by calculating the spatial position relationship between each household name point and the vector surface of each household on each floor, and then associating the annotation information in each household name point to the vector surface of the corresponding household, includes:

[0026] Calculate the spatial position relationship between each household name point and the vector surface of each household on each floor. Based on the spatial positions of each household name point and the vector surface of each household on each floor, use the ray method to determine the intersecting household name points and vector surfaces, and then associate the annotation information in the household name point to the vector surface.

[0027] In one embodiment, stacking the vector surfaces of each floor together based on the spatial coordinates of the alignment points in the CAD data includes:

[0028] Taking the hierarchical household plan of the first floor above ground as the alignment target, extract the spatial coordinates of the alignment points on each floor. For each floor except the first floor, use the four-parameter transformation model to calculate the translation distance and rotation angle for moving each floor to the first floor, and overlay the vector surfaces of each floor together.

[0029] In one embodiment, the four-parameter transformation model is:

[0030]

[0031] Wherein, is the plane coordinate of the alignment point of the layer to be aligned, is the plane coordinate of the alignment point of the first floor above ground, t x 、t y are the translation parameters, and Δθ is the rotation parameter.

[0032] In one embodiment, supplement and improve the modeling data source based on the vector surfaces of each floor and the auxiliary modeling data through elevation calculation and cloning operations, including:

[0033] Calculate the starting elevation of each floor according to the starting elevation of the first floor above ground and the floor height in the auxiliary modeling data of the vector surfaces of each floor;

[0034] Clone the vector surfaces of the standard floors with the same form to form the vector surfaces of each floor with the same form, and synchronously modify the floor number, floor name, and starting elevation of this floor according to the clone serial number.

[0035] In one embodiment, move the vector surfaces of each floor to the corresponding elevation position and perform stretching modeling to form a three-dimensional geometric body of building hierarchical household, including:

[0036] Move each vector surface to the corresponding elevation according to the starting elevation of each floor;

[0037] Perform stretching processing on each vector surface according to the floor height of each floor to form a three-dimensional geometric body of building hierarchical household.

[0038] In one embodiment, move the three-dimensional geometric body of building hierarchical household to the real coordinates of the property under the earth surface projection coordinate system based on the marked points and registration table in the CAD data, organize the data of the three-dimensional geometric body of building hierarchical household in the form of building, floor, and household, and output the three-dimensional model of building hierarchical household in IFC format, including:

[0039] Taking the spatial coordinates recorded in the registration table as the registration target, extracting the coordinates of the registration points, calculating the transformation parameters from the registration points to the registration target through affine transformation, moving the three-dimensional geometric bodies of the building stratified household by household to the real coordinates of the property under the earth surface projection coordinate system, organizing the data of the three-dimensional geometric bodies of the building stratified household by household in the form of building, floor and household, and outputting the three-dimensional model of the building stratified household by household in IFC format.

[0040] The above method for constructing a three-dimensional model of a building stratified household by household based on a property stratified household map preprocesses the CAD data of the property stratified household map, stores the annotation information and vector elements in the CAD data in separate layers, adds annotation points and annotation frames to the CAD data, and creates a building plot table and a registration table containing auxiliary modeling data for the property. The annotation points include alignment points, registration points, household name points and floor number points. Based on the vectors in the CAD data, a vector surface for each household on each floor of the property is constructed using the left-turn algorithm. Based on the annotation information of the floor number points in the CAD data, the auxiliary modeling data contained in the building plot table is associated with the vector surface of each household on the corresponding floor. By calculating the spatial position relationship between each household name point and the vector surface of each household on each floor, the annotation information in each household name point is then associated with the vector surface of the corresponding household. Based on the spatial coordinates of the alignment points in the CAD data, the vector surfaces of each floor are stacked together. Based on the vector surfaces of each floor and the auxiliary modeling data, the modeling data source is supplemented and improved through elevation calculation and cloning operations. The vector surfaces of each floor are moved to the corresponding elevation positions and stretched for modeling to form three-dimensional geometric bodies of the building stratified household by household. Based on the annotation points and the registration table in the CAD data, the three-dimensional geometric bodies of the building stratified household by household are moved to the real coordinates of the property under the earth surface projection coordinate system, the data of the three-dimensional geometric bodies of the building stratified household by household is organized in the form of building, floor and household, and a three-dimensional model of the building stratified household by household in IFC format is output. Thereby, the modeling efficiency and quality are improved. Brief Description of the Drawings

[0041] Figure 1 It is a schematic flow chart of a method for constructing a three-dimensional model of a building stratified household by household based on a property stratified household map in an embodiment;

[0042] Figure 2 It is a CAD data diagram of a property stratified household in an embodiment;

[0043] Figure 3 It is a schematic diagram of partial data in a building plot table in an embodiment;

[0044] Figure 4 It is a schematic diagram of registration table data in an embodiment;

[0045] Figure 5 It is a display diagram of the vertical alignment result in an embodiment;

[0046] Figure 6 It is a display diagram of the 3D modeling result in an embodiment. Detailed implementation manners

[0047] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0048] In one embodiment, as Figure 1 shown, a method for constructing a building floor-by-floor and household-by-household 3D model based on a real estate floor-by-floor and household-by-household map is provided. Taking the application of this method to a terminal as an example for illustration, the method includes the following steps:

[0049] S1. Data preprocessing: Preprocess the CAD data of the real estate floor-by-floor and household-by-household map, store the annotation information and vector elements in the CAD data in separate layers, add annotation points and annotation frames to the CAD data, and create a building plot table and a registration table for the real estate that contain auxiliary modeling data. The annotation points include alignment points, registration points, household name points and floor number points.

[0050] Among them, the annotation points and annotation frames can be added manually or automatically through a program.

[0051] Among them, the building plot table refers to an auxiliary modeling data source constructed using Microsoft Excel. The content in the field information includes building number, floor number, floor name, floor height, floor mark, number of standard floors, alignment point name, etc., and the content can be expanded according to actual business requirements.

[0052] Among them, the registration table refers to an auxiliary modeling data source constructed using Microsoft Excel, and the content includes the name of the registration point, the X coordinate of the registration point, the Y coordinate of the registration point and the Z coordinate of the registration point.

[0053] S2. Topological surface construction: Based on the vectors in the CAD data, use the left-turn algorithm to construct the vector surfaces of each household on each floor of the real estate.

[0054] S3. Graphic-attribute association: Based on the annotation information of the floor number points in the CAD data, associate the auxiliary modeling data included in the building plot table to the vector surfaces of each household on the corresponding floor; by calculating the spatial position relationship between each household name point and the vector surfaces of each household on each floor, and then associate the annotation information in each household name point to the vector surface of the corresponding household.

[0055] Among them, the graphic-attribute association realizes the information association between the building plot table, annotation points, annotation frames and vector surfaces by using field matching and spatial calculation.

[0056] S4, Vertical Alignment: Based on the spatial coordinates of the alignment points in the CAD data, stack the vector surfaces of each layer together.

[0057] Among them, vertical alignment calculates the translation distance and rotation angle according to the spatial coordinates of the alignment points marked on each layer, and realizes stacking the data of each layer together.

[0058] S5, Stratification and Household Division: Based on the vector surfaces of each layer and the auxiliary modeling data, supplement and improve the modeling data source through elevation calculation and cloning operations.

[0059] Among them, stratification and household division uses the data relationship between the vector surfaces of each layer to obtain all the vector surfaces covering each household on each layer of the to-be-built building, including the following steps: The first step: Calculate the starting elevation of each layer based on the starting elevation of the first above-ground floor and the floor height of each layer; The second step: Clone the standard floor, and synchronously modify the floor number, floor name, and starting elevation according to the clone serial number.

[0060] S6, 3D Modeling: Move the vector surfaces of each layer to the corresponding elevation positions and perform stretching modeling to form a 3D geometric body of the building with stratified households.

[0061] Among them, 3D modeling includes the following steps: The first step: Move each vector surface to the corresponding elevation according to the information in the "starting elevation" field; The second step: Stretch each vector surface according to the information in the "floor height" field to form a 3D geometric body of the building with stratified households.

[0062] S7, Spatial Registration: Based on the marked points and the registration table in the CAD data, move the 3D geometric body of the building with stratified households to the real coordinates of the property under the earth surface projection coordinate system.

[0063] Among them, spatial registration takes the spatial coordinates recorded in the registration table as the registration target, extracts the coordinates of the registration points G1, G2, G3, and G4, calculates the transformation parameters from the registration points to the registration target through affine transformation, so as to move the 3D geometric body of the building with stratified households to the correct geographical coordinates and realize spatial registration.

[0064] S8, Model Output: Organize the data of the 3D geometric body of the building with stratified households in the form of building, layer, and household, and output the 3D model of the building with stratified households in IFC format.

[0065] Step S8, Based on the marked points and the registration table in the CAD data, move the 3D geometric body of the building with stratified households to the real coordinates of the property under the earth surface projection coordinate system, organize the data of the 3D geometric body of the building with stratified households in the form of building, layer, and household, and output the 3D model of the building with stratified households in IFC format.

[0066] The above method for constructing a three-dimensional model of building floor-by-floor and household-by-household based on the building floor-by-floor and household-by-household map preprocesses the CAD data of the building floor-by-floor and household-by-household map, stores the annotation information and vector elements in the CAD data in separate layers, adds annotation points and annotation frames to the CAD data, and creates a building plot table and a registration table for the building that contain auxiliary modeling data. The annotation points include alignment points, registration points, household name points, and floor number points. Based on the vectors in the CAD data and using the left-turn algorithm, a vector surface for each household on each floor of the building is constructed. Based on the annotation information of the floor number points in the CAD data, the auxiliary modeling data contained in the building plot table is associated with the vector surface of each household on the corresponding floor. By calculating the spatial position relationship between each household name point and the vector surface of each household on each floor, the annotation information in each household name point is then associated with the vector surface of the corresponding household. Based on the spatial coordinates of the alignment points in the CAD data, the vector surfaces of each floor are stacked together. Based on the vector surfaces of each floor and the auxiliary modeling data, the modeling data source is supplemented and improved through elevation calculation and cloning operations. The vector surfaces of each floor are moved to the corresponding elevation positions and stretched for modeling to form a three-dimensional geometry of building floor-by-floor and household-by-household. Based on the annotation points and the registration table in the CAD data, the three-dimensional geometry of building floor-by-floor and household-by-household is moved to the real coordinates of the building under the earth surface projection coordinate system, and the data of the three-dimensional geometry of building floor-by-floor and household-by-household is organized in the form of building, floor, and household, and an IFC-format three-dimensional model of building floor-by-floor and household-by-household is output. Thereby, the modeling efficiency and quality are improved.

[0067] In one embodiment, the preprocessing of the CAD data of the building floor-by-floor and household-by-household map, storing the annotation information and vector elements in the CAD data in separate layers, adding annotation points and annotation frames to the CAD data, and creating a building plot table and a registration table for the building that contain auxiliary modeling data includes:

[0068] Using Autodesk CAD to preprocess the CAD data of the building floor-by-floor and household-by-household map, storing the annotation information and vector elements in the CAD data in separate layers, adding annotation points and annotation frames to the CAD data, and creating a building plot table and a registration table for the building that contain auxiliary modeling data.

[0069] Among them, based on the CAD data of the building floor-by-floor and household-by-household map, new annotation points and annotation frames are added using Autodesk CAD. The annotation points can be classified into alignment points, registration points, household name points, and floor number points according to their functions; the annotation frames are rectangular surfaces used to group the vector elements of the same floor together.

[0070] In one embodiment, the constructing of the vector surface for each household of the building based on the vectors in the CAD data and using the left-turn algorithm includes:

[0071] Traverse all vector elements in the CAD data, introduce computational geometry algorithms to detect the intersection points of vector elements, and break at the intersections; for vector elements with overlapping phenomena, only retain one of the vector elements; traverse all the retained vector elements, and use the left-turn algorithm to reconstruct the vector surfaces of each household on each floor of the property.

[0072] In one embodiment, associating the auxiliary modeling data included in the building table to the vector surfaces of each household on the corresponding floor based on the annotation information of the floor number points in the CAD data includes:

[0073] Match the annotation information of the floor number points in the CAD data with the field information in the building table to determine the matching annotation information and field information, and associate the entire row information of the field information in the auxiliary modeling data of the building table to the floor number point corresponding to the annotation information; calculate the spatial positions of each floor number point and each annotation box, and based on the spatial positions of each floor number point and each annotation box, use the ray method to determine the intersecting floor number points and annotation boxes, and associate the auxiliary modeling data associated with the floor number point to the annotation box; calculate the spatial positions of each annotation box and the vector surfaces of each household on each floor, and based on the spatial positions of each annotation box and the vector surfaces of each household on each floor, use the polygon intersection detection function to determine the intersecting annotation boxes and vector surfaces, and associate the auxiliary modeling data associated with the annotation box to the vector surface that intersects it.

[0074] Among them, the ray method, also known as the ray crossing algorithm, the judgment principle of this algorithm is: if a point is inside a polygon, draw a horizontal ray to the right from this point, and the number of intersections with the polygon is odd; if it is outside the polygon, the number of intersections is even; if it is on the polygon boundary, the number of intersections is uncertain, sometimes even and sometimes odd.

[0075] Among them, the vector surface of a certain floor is composed of the vector surfaces of all households on that floor.

[0076] Among them, the polygon intersection detection function uses the polygon intersection detection function in the CGAL library for surface-to-surface intersection.

[0077] In one embodiment, associating the annotation information in each household name point to the vector surface of the corresponding household by calculating the spatial position relationship between each household name point and the vector surfaces of each household on each floor includes:

[0078] Calculate the spatial position relationship between each household name point and the vector surfaces of each household on each floor, and based on the spatial positions of each household name point and the vector surfaces of each household on each floor, use the ray method to determine the intersecting household name points and vector surfaces, and then associate the annotation information in the household name point to the vector surface.

[0079] In one embodiment, stacking the vector surfaces of each layer based on the spatial coordinates of the alignment points in the CAD data includes:

[0080] Taking the hierarchical household plan of the first above-ground floor as the alignment target, extracting the spatial coordinates of the alignment points of each layer, and for each layer other than the first floor, using a four-parameter transformation model to calculate the translation distance and rotation angle for moving each other layer to the first floor, and stacking the vector surfaces of each layer together.

[0081] In one embodiment, the four-parameter transformation model is:

[0082]

[0083] Wherein, is the planar coordinate of the alignment point of the layer to be aligned, is the planar coordinate of the alignment point of the first above-ground floor, t x 、t y are translation parameters, and Δθ is a rotation parameter.

[0084] In one embodiment, supplementing and improving the modeling data source based on the vector surfaces of each layer and the auxiliary modeling data through elevation calculation and cloning operations includes:

[0085] Calculating the starting elevation of each layer according to the starting elevation of the first above-ground floor and the floor height of each layer in the auxiliary modeling data of the vector surfaces of each layer;

[0086] Cloning the vector surfaces of the standard floors with the same form to form the vector surfaces of each layer with the same form, and synchronously modifying the floor number, floor name, and starting elevation of this layer according to the cloning serial number.

[0087] In one embodiment, moving the vector surfaces of each layer to the corresponding elevation position and performing stretching modeling to form a three-dimensional geometric body of hierarchical household division of the building includes:

[0088] Moving each vector surface to the corresponding elevation according to the starting elevation of each layer;

[0089] Performing stretching processing on each vector surface according to the floor height of each layer to form a three-dimensional geometric body of hierarchical household division of the building.

[0090] In one embodiment, moving the three-dimensional geometric body of hierarchical household division of the building to the real coordinates of the property under the earth surface projection coordinate system based on the marked points and registration table in the CAD data, organizing the data of the three-dimensional geometric body of hierarchical household division of the building in the form of building, floor, and household, and outputting a three-dimensional model of hierarchical household division of the building in IFC format includes:

[0091] Using the spatial coordinates recorded in the registration table as the registration target, extracting the coordinates of the registration points, calculating the transformation parameters from the registration points to the registration target through affine transformation, moving the three-dimensional building geometry by building and household to the real coordinates of the property in the earth surface projection coordinate system, organizing the three-dimensional building geometry data by building, floor, and household, and outputting the three-dimensional building model by building and household in IFC format.

[0092] The above method for constructing a three-dimensional building model by building and household based on the property map by building and household realizes the rapid construction of a three-dimensional building model by building and household through a complete set of standardized processing procedures such as data preprocessing, topological surface construction, graph-attribute association, building and household stratification, vertical alignment, building and household stratification, three-dimensional modeling, spatial registration, and model output. Among them, the standardized data preprocessing provides a data source that meets the requirements for the subsequent modeling process. In particular, through the simple interaction method of information annotation, the unified and efficient processing of CAD data sources with different regions and qualities is realized, improving the applicability of the modeling method while ensuring the modeling efficiency. In addition, by enriching the data in the building table, a three-dimensional building model by building and household that meets different business requirements can be constructed. By designing a more applicable topological surface construction scheme, vector surfaces for each floor and household can be generated accurately and quickly. This scheme is not only applicable to CAD data containing multiple vector element types, but also reduces the dependence on automatic recognition algorithms while ensuring efficiency and accuracy. By proposing a graph-attribute association method based on field matching and spatial calculation, the accurate association between the vector surfaces of each floor and household and the auxiliary modeling data is realized, solving the problem that the existing annotation information in CAD data cannot meet the modeling needs.

[0093] In order to achieve the vertical alignment and spatial registration of the vector surfaces of each floor, this application adopts the planar four-parameter transformation and affine transformation methods, solving the problems of the relative placement of the vector data of each floor and the lack of real geographical coordinates in the property map by building and household, and avoiding the cumbersome and inefficient manual alignment in the actual modeling process. In addition, according to the attribute information of each floor, the three-dimensional building geometry by building and household is automatically constructed by the stretching modeling method and output as a three-dimensional building model by building and household in IFC format, significantly improving the modeling efficiency and quality and better meeting the actual needs of the construction of the building and household model in the urban information model data processing system.

[0094] In one embodiment, a method for constructing a three-dimensional building model by building and household based on the property map by building and household includes the following steps:

[0095] Step 1, data preprocessing: Obtain the property map data by building and household to be modeled. The property map data in this example can be CAD data in DXF format or DWG format, and is stored in file units by "building", that is, the data of each floor within the same building is in the same CAD file, such asFigure 2 As shown below. The specific preprocessing steps are as follows:

[0096] Step 11, Layer management: Using Autodesk CAD, place the vector elements used in the original property floor plan CAD data on the same layer, and create a new layer for storing annotation information.

[0097] Step 12, Information annotation: Using the "Annotation" and "Rectangle" functions in Autodesk CAD, create various types of annotation information in the new layer to support subsequent modeling. Specifically, first create a rectangular area for each floor to clarify the area range of each floor, and add an annotation at the upper left vertex of the rectangular area. The annotation content is "L + floor number", which is called the "floor number point"; add annotations at two identical positions on each floor. The annotation content for the above-ground floors is "PL + floor number + serial number", and the annotation content for the underground floors is "PB + floor number + serial number", which is called the "alignment point"; add annotations at the four corner points of the outer contour of the first above-ground floor. The annotation content is "G + serial number", which is called the "registration point"; add annotations inside each closed area. The annotation content is "unit number + household number", which is called the "household name point". Information annotation realizes the floor area division and information supplementation of the original CAD data through simple interactive operations, providing information support for the subsequent modeling process.

[0098] Step 13, Create building tables and registration tables: The building tables and registration tables are data sources for storing auxiliary modeling data, which can be in XLS format or XLSX format. In this embodiment, use Microsoft Excel to create the above data, as Figure 3 and Figure 4 shown.

[0099] Step 2, Topological surface construction: Traverse all vector elements in the CAD data, introduce computational geometry algorithms to detect vector intersections, and break at the intersections; for vector elements with overlapping phenomena, only retain one of them; traverse all the remaining vector elements, and apply the left-turn algorithm to reconstruct the vector surfaces of each floor and each household.

[0100] Step 3, Map-attribute association. Through field matching and spatial calculation, associate the auxiliary modeling data in the building tables to the reconstructed vector surfaces of each floor and each household. Further, by calculating the spatial position of the household name points and the vector surfaces, associate the annotation information of the household name points to each vector surface.

[0101] Step 4, Vertical alignment. Take the first above-ground floor as the target reference floor. The remaining floors are the floors to be aligned. Calculate the translation distance and rotation angle required to move the floors to be aligned to the target reference floor based on the alignment point coordinates of the target reference floor and the alignment point coordinates of the floors to be aligned. Finally, stack the vector surfaces of each floor together through translation and rotation, as Figure 5 shown.

[0102] Taking the alignment points of the first layer as an example, the alignment points of the first layer include PL11 and PL12.

[0103] Step 5: Stratify and divide households. Calculate the starting elevation of each layer based on the starting elevation of the first floor above ground and the floor height of each layer; clone the standard layer and synchronously modify the layer number, layer name, and starting elevation according to the clone number to obtain a stratified and divided household vector surface covering all layers and households of the building to be constructed.

[0104] Step 6: 3D modeling. Move each vector surface to the corresponding elevation according to the information in the "starting elevation" field; perform stretching processing on each vector surface according to the information in the "floor height" field to form a set of 3D geometric bodies for stratified and divided households of the building, as Figure 6 shown.

[0105] Step 7: Spatial registration. Move the 3D geometric bodies of the stratified and divided households of the building to the correct geographical location using the real geographical coordinates provided by the registration table, as shown in Figure 4 shown. Specifically, taking the spatial coordinates recorded in the registration table as the registration target, extract the coordinates of the registration points G1, G2, G3, and G4, and calculate the transformation parameters from the registration points to the registration target through affine transformation, so as to move the 3D geometric bodies of the stratified and divided households of the building to the correct geographical coordinates.

[0106] Step 8: Model output. Traverse the set of 3D geometric bodies of the stratified and divided households of the building constructed, and determine whether they belong to a household object. If so, merge them into one household object; if the geometric bodies have the same "layer number" field, combine them into one layer object; finally, organize the data of the 3D geometric bodies of the stratified and divided households of the building in the form of "building - layer - household" and output a 3D model of the stratified and divided households of the building in IFC format.

[0107] It should be understood that although Figure 1 each step in the flowchart of Figure 1 is shown in sequence according to the arrow indication, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover,

[0108] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0109] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A method for constructing a three-dimensional model of a building layered and householded structure based on a real estate layered and householded structure map, characterized in that: The method comprises: S1, data preprocessing: preprocessing the CAD data of the real estate layered and household-by-household map, storing the annotation information and vector elements in the CAD data in layers, adding annotation points and annotation boxes to the CAD data, and creating a building table and a registration table containing auxiliary modeling data for the real estate, wherein the annotation points include alignment points, registration points, household name points, and layer number points; S2, topological surface construction: constructing vector surfaces of each household on each floor of the property based on the vectors in the CAD data and using a left-turn algorithm; S3, figure attribute association: based on the annotation information of the floor number point in the CAD data, the auxiliary modeling data contained in the building table is associated with the vector surface of each household in the corresponding floor; by calculating the spatial position relationship between each household name point and the vector surface of each household in each floor, the annotation information in each household name point is associated with the vector surface of the corresponding household; S4, vertical alignment: superimposing the vector surfaces of each layer based on the spatial coordinates of the alignment points in the CAD data; S5, layered and household-based: Based on the vector surface and auxiliary modeling data of each layer, the modeling data source is supplemented and improved through elevation calculation and cloning operations; S6, 3D modeling: Move the vector surface of each layer to the corresponding elevation position, and perform stretching modeling to form a 3D geometric body of the building layered and householded; S7, spatial registration: Based on the annotation points and registration table in the CAD data, the three-dimensional geometric bodies of the building layers and households are moved to the real coordinates of the property in the projection coordinate system on the earth's surface; S8, model output: organize the 3D geometric data of the building by layers and households in the form of buildings, floors and households, and output the 3D model of the building by layers and households in IFC format.

2. The method according to claim 1, characterized in that The method of preprocessing the CAD data of the real estate layered and household-by-household map, storing the annotation information and vector elements in the CAD data in layers, adding annotation points and annotation boxes to the CAD data, and creating a building table and a registration table containing auxiliary modeling data for the real estate includes: Autodesk CAD is used to preprocess the CAD data of the property layer and household map, the annotation information and vector elements in the CAD data are stored in layers, annotation points and annotation boxes are added to the CAD data, and a building table and a registration table containing auxiliary modeling data for the property are created.

3. The method according to claim 1, characterized in that The vector surface of each household of the real estate is constructed based on the vectors in the CAD data and using a left-turn algorithm, including: Traversing all vector elements in the CAD data, introducing a computational geometry algorithm to detect intersections of the vector elements, and breaking them at the intersections; For overlapping vector elements, only one of them is retained; All the retained vector features are traversed, and the vector surface of each household on each floor of the property is reconstructed using the left-turn algorithm.

4. The method according to claim 1, characterized in that The method of associating the auxiliary modeling data contained in the building table with the vector surface of each household in the corresponding layer based on the annotation information of the layer number point in the CAD data includes: Matching the annotation information of the floor number point in the CAD data with the field information in the building table, determining the matching annotation information and field information, and associating the entire row of the row where the field information is located in the auxiliary modeling data of the building table to the floor number point corresponding to the annotation information; Calculate the spatial position of each layer number point and each annotation frame, and based on the spatial position of each layer number point and each annotation frame, use the ray method to determine the intersecting layer number points and annotation frames, and associate the auxiliary modeling data associated with the layer number point to the annotation frame; Calculate the spatial position of each annotation box and the vector surface of each household on each layer. Based on the spatial position of each annotation box and the vector surface of each household on each layer, use the polygon intersection detection function to determine the intersecting annotation boxes and vector surfaces, and associate the auxiliary modeling data associated with the annotation box to the vector surface intersecting with it.

5. The method according to claim 1, characterized in that The method calculates the spatial position relationship between each household name point and the vector surface of each household in each layer, and then associates the annotation information in each household name point with the vector surface of the corresponding household, including: Calculate the spatial position relationship of each household name point and the vector surface of each household on each layer. Based on the spatial position of each household name point and the vector surface of each household on each layer, use the ray method to determine the intersecting household name points and vector surfaces, and then associate the annotation information in the household name point to the vector surface.

6. The method according to claim 1, characterized in that The step of stacking the vector surfaces of each layer based on the spatial coordinates of the alignment points in the CAD data includes: Taking the layered and household map of the first floor as the alignment target, the spatial coordinates of the alignment points of each layer are extracted. For each layer except the first floor, the four-parameter transformation model is used to calculate the translation distance and rotation angle of each layer to the first floor, and the vector surfaces of each layer are superimposed together.

7. The method according to claim 6, characterized in that The four-parameter conversion model is: in, is the plane coordinate of the alignment point of the layer to be aligned, is the plane coordinate of the alignment point on the ground floor, t x ,t y is the translation parameter, and Δθ is the rotation parameter.

8. The method according to claim 1, characterized in that: The vector surface and auxiliary modeling data based on each layer are used to supplement and improve the modeling data source through elevation calculation and cloning operations, including: Calculate the starting elevation of each layer based on the starting elevation of the first floor and the height of each layer in the auxiliary modeling data of each layer's vector surface; The vector surfaces of the standard layers with the same form are cloned to form vector surfaces of each layer with the same form, and the layer number, layer name and starting elevation of the layer are synchronously modified according to the clone sequence number.

9. The method according to claim 8, characterized in that The vector surface of each layer is moved to the corresponding elevation position, and stretched and modeled to form a three-dimensional geometric body of the building layered and householded, including: According to the starting elevation of each layer, each vector surface is moved to the corresponding elevation; According to the height of each floor, each vector surface is stretched to form a three-dimensional geometric body with different layers and households in the building.

10. The method according to claim 1, characterized in that The method of moving the 3D geometric body of the building by layer and household by household to the real coordinates of the property in the projection coordinate system of the earth surface based on the marked points and the registration table in the CAD data, organizing the 3D geometric body data of the building by layer and household by household in the form of building, floor and household, and outputting the 3D model of the building by layer and household by household in IFC format includes: The spatial coordinates recorded in the registration table are used as the registration target, the coordinates of the registration points are extracted, and the transformation parameters from the registration points to the registration target are calculated through affine transformation. The three-dimensional geometric body of the building layered and householded is moved to the real coordinates of the property in the projection coordinate system of the earth's surface, and the three-dimensional geometric body data of the building layered and householded is organized in the form of buildings, floors, and households, and the three-dimensional model of the building layered and householded is output in IFC format.

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