Hierarchical extraction method, system and equipment for three-dimensional model of marine disaster prevention and disaster body

Abstract

The application provides a hierarchical extraction method, system and equipment for a three-dimensional model of a marine disaster prevention disaster-bearing body, which comprises the following steps: by performing hierarchical coding and naming on each entity element in a two-dimensional geographic entity vector file, the executable performance of identification and determination in the monomerization step of a three-dimensional geographic scene can be effectively improved, the feature conditions of the identification and determination of the two-dimensional geographic entity are accelerated according to key field information, the element range of the buffer zone to be established is quickly located, the cutting space range is effectively and accurately provided according to the virtual three-dimensional space polyhedron, the naming of the monomerized elements of the three-dimensional geographic entity is realized according to the naming rules, the object is quickly and automatically picked up according to the three-level classification logical attribution relationship of the elements, the folder organization is automatically established synchronously, and the automatic extraction processing of the achievement file is efficiently completed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, in particular to a hierarchical extraction method, system and equipment of a marine disaster prevention and disaster-bearing body three-dimensional model. BACKGROUND

[0002] At present, the three-dimensional geographic entity model construction mainly applies the automatic rapid construction technology and method, specifically, multi-angle image data, high-precision positioning data, digital surface model data, texture data and the like are collected based on the oblique photogrammetry technology, the multi-source data is fused and processed, the rapid construction of the three-dimensional oblique model is realized, the geometric characteristics of the model are continuous triangular net structure, the generation is realized through texture mapping assignment, the various geographic element models have the overall continuous characteristics, the three-dimensional entity element observation can be realized, but the separate processing and analysis of different geographic element models cannot be realized. Moreover, the three-dimensional geographic entity model obtained by using the above existing technology is saved in the form of tiles, the tile data has multi-level (LOD) data characteristics, but does not have the functions of single model classification, separate selection and spatial analysis and the like. SUMMARY

[0003] In view of the above problems, the present application is proposed in order to provide a hierarchical extraction method, system and equipment of a marine disaster prevention and disaster-bearing body three-dimensional model which overcomes the above problems or at least partially solves the above problems.

[0004] In one aspect of the present application, a hierarchical extraction method of a marine disaster prevention and disaster-bearing body three-dimensional model is provided, the method comprises:

[0005] S11, acquiring a three-dimensional geographic scene model and a two-dimensional geographic entity vector file of a marine storm surge area;

[0006] S12, performing hierarchical coding and naming on each entity element in the two-dimensional geographic entity vector file;

[0007] S13, identifying each entity element and the corresponding entity polygon boundary according to the name of the entity element, the entity polygon boundary of the traffic, water conservancy and water system two-dimensional geographic entity does not perform buffering, and the entity polygon boundary of the building / structure and facility is respectively extended outward to generate the corresponding entity buffer zone boundary;

[0008] S14, positioning the corresponding area boundary in the three-dimensional geographic scene model according to the entity buffer zone boundary of the building / structure and facility entity and the entity polygon boundary of the other entity elements except the building / structure and facility entity, and stretching each area boundary in the positive and negative directions of the Z-axis, to form a plurality of virtual three-dimensional space polyhedrons;

[0009] S15, the virtual three-dimensional space polyhedron corresponding to the building and facility entity and the three-dimensional geographic scene model are subjected to spatial relationship detection, so as to respectively judge whether the building and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional space polyhedron at the corresponding spatial position, if yes, it is determined that the corresponding virtual three-dimensional space polyhedron satisfies the spatial relationship, and the optimal virtual three-dimensional space polyhedron is obtained, otherwise, step S16 is executed;

[0010] S16, for the virtual three-dimensional space polyhedron which does not satisfy the spatial relationship, the corresponding entity buffer boundary is dynamically adjusted, and step S14 is returned until the virtual three-dimensional space polyhedron corresponding to the building and facility entity all satisfies the spatial relationship;

[0011] S17, the three-dimensional geographic scene model is subjected to physical space cutting by using the optimal virtual three-dimensional space polyhedron, and a plurality of three-dimensional geographic entity single model files are obtained, and the three-dimensional geographic entity single model file is named and hierarchically extracted according to the name of each entity element in the two-dimensional geographic entity vector file.

[0012] Another aspect of the present application also provides a hierarchical extraction system of a three-dimensional model of a marine disaster prevention disaster-bearing body, the system comprising:

[0013] A data acquisition module is configured to acquire a three-dimensional geographic scene model of a marine storm surge area and a two-dimensional geographic entity vector file;

[0014] A naming module is configured to hierarchically encode and name each entity element in the two-dimensional geographic entity vector file;

[0015] A boundary buffer module is configured to identify each entity element and the entity polygon boundary corresponding to the entity element according to the name of the entity element, and respectively extend the building and facility entity polygon boundary outward to generate the corresponding entity buffer boundary;

[0016] A space polyhedron generation module is configured to locate the corresponding region boundary in the three-dimensional geographic scene model according to the entity buffer boundary of the building and facility entity and the entity polygon boundary of other entity elements except the building and facility entity, and stretch each region boundary in the positive and negative directions of the Z-axis to form a plurality of virtual three-dimensional space polyhedrons;

[0017] A spatial relationship detection module is configured to detect the spatial relationship between the virtual three-dimensional space polyhedron corresponding to the building and facility entity and the three-dimensional geographic scene model, so as to respectively judge whether the building and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional space polyhedron at the corresponding spatial position, if yes, it is determined that the corresponding virtual three-dimensional space polyhedron satisfies the spatial relationship, otherwise, the virtual three-dimensional space polyhedron does not satisfy the spatial relationship;

[0018] The boundary adjustment module is used to dynamically adjust the boundary of the corresponding entity buffer for virtual three-dimensional spatial polyhedra that do not satisfy the spatial relationship, and return to the spatial polyhedron generation module to re-execute the spatial polyhedron generation step until the spatial relationship detection module detects that the current virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities all satisfy the spatial relationship, thus obtaining the optimal virtual three-dimensional spatial polyhedron.

[0019] The single-entity model extraction module is used to physically cut the 3D geographic scene model using the optimal virtual 3D space polyhedron to obtain multiple 3D geographic entity single-entity model files. The 3D geographic entity single-entity model files are named and extracted hierarchically according to the names of each entity element in the 2D geographic entity vector file.

[0020] Another aspect of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor; when the computer program is executed by the processor, it implements the steps of the graded extraction method for the three-dimensional model of marine disaster-bearing bodies as described above.

[0021] Another aspect of the present invention provides a computer program product, wherein the computer program product stores a computer program, and when the computer program is executed by a processor, it implements the steps of the graded extraction method for the three-dimensional model of the marine disaster prevention and mitigation body as described above.

[0022] The hierarchical extraction method, system, and device for three-dimensional models of marine disaster-bearing bodies provided in this invention can effectively improve the executability of identification and judgment in the individualization step of three-dimensional geographic scenes by hierarchically encoding and naming each entity element in the two-dimensional geographic entity vector file. It accelerates the identification and judgment of two-dimensional geographic entities based on key field information, quickly locates the range of elements that need to be buffered, effectively and accurately provides the cutting space range based on the virtual three-dimensional space polyhedron, and realizes the naming of individual elements of three-dimensional geographic entities according to naming rules. Based on the three-level classification logic of elements, it quickly and automatically picks up the extraction objects, synchronously and automatically creates folder organization, and efficiently completes the automatic output of result files.

[0023] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0025] Figure 1 A flowchart of a hierarchical extraction method for a three-dimensional model of a marine disaster-bearing body provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the name encoding rules in the hierarchical extraction method of the three-dimensional model of marine disaster-bearing bodies provided in the embodiments of the present invention;

[0027] Figure 3 The structural block diagram of the hierarchical extraction system for the three-dimensional model of marine disaster-bearing bodies proposed in this embodiment of the invention. Detailed Implementation

[0028] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0029] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0030] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art and should not be interpreted in an idealized or overly formal sense unless specifically defined.

[0031] Figure 1 The flowchart illustrating a method for hierarchical extraction of a three-dimensional model of a marine disaster-bearing body according to an embodiment of the present invention is shown schematically. (Refer to...) Figure 1 The hierarchical extraction method for the three-dimensional model of marine disaster-bearing bodies in this embodiment of the invention specifically includes the following steps:

[0032] S11. Obtain the three-dimensional geographic scene model and two-dimensional geographic entity vector file of the marine storm surge area.

[0033] In this embodiment, basic data preparation is performed first. Specific steps include: collecting a 3D geographic scene mesh model of the marine storm surge area and collecting 2D geographic entity vector files of the marine storm surge area. The spatial coverage relationship between the 2D geographic entities corresponding to the 2D geographic entity vector files and the 3D geographic scene data is checked to determine that the 2D geographic entities achieve full spatial coverage of the 3D geographic scene.

[0034] S12. Hierarchical coding and naming of each entity element in the two-dimensional geographic entity vector file.

[0035] In this embodiment, the hierarchical coding and naming of entity elements specifically involves hierarchically coding and naming each entity element according to its multi-level classification code. Specifically, the geographic entity elements in the vector file are classified at multiple levels based on their attribute information. In one specific embodiment, this can be a three-level classification. The first-level classification can be divided into buildings / structures and facilities, water conservancy, water bodies, and transportation according to geographic elements. Then, based on a preset hierarchical classification logic rule, the various categories included in each category are further subdivided in a finer-grained manner to obtain the three-level classification information.

[0036] S13. Identify each entity element and its corresponding entity patch boundary according to the name of the entity element, and extend the entity patch boundary of buildings / structures and facilities outward to generate the corresponding entity buffer boundary.

[0037] In this embodiment, only buildings and facilities are buffered, and not all entities are buffered. The boundaries of other two-dimensional geographic entities such as transportation, water conservancy, and water systems are not buffered. In subsequent steps, other entities (water, roads, etc.) can be directly cut by generating polyhedra based on the boundaries of the two-dimensional geographic entities.

[0038] S14. Based on the entity buffer boundaries of buildings / structures and facilities, as well as the entity patch boundaries of other entity elements besides buildings / structures and facilities, locate the corresponding region boundaries in the 3D geographic scene model, and stretch each region boundary in the positive and negative directions of the Z-axis to form multiple virtual 3D spatial polyhedra.

[0039] In this embodiment, since the surface of the geographical scene is uneven and there is a negative Z-axis direction at the bottom of the building, the boundaries of each region can be stretched in the positive and negative directions of the Z-axis. By stretching in the negative direction, it is ensured that the model surface in the negative direction is also included in the formed virtual three-dimensional space polyhedron.

[0040] S15. Perform spatial relationship detection on the virtual three-dimensional spatial polyhedrons corresponding to the building / structure and facility entities and the three-dimensional geographic scene model, so as to determine whether the building / structure and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional spatial polyhedrons of the corresponding spatial locations. If so, determine that the corresponding virtual three-dimensional spatial polyhedrons satisfy the spatial relationship and obtain the optimal virtual three-dimensional spatial polyhedron; otherwise, proceed to step S16.

[0041] In this embodiment, the optimal virtual 3D spatial polyhedron refers to all virtual 3D spatial polyhedra obtained when all building / structure and facility model elements in the 3D geographic scene model are located within the virtual 3D spatial polyhedron at their corresponding spatial positions. This includes virtual 3D spatial polyhedra containing building / structure and facility entities, as well as other entity elements besides building / structure and facility entities.

[0042] S16. For virtual three-dimensional spatial polyhedra that do not satisfy the spatial relationship, dynamically adjust the boundary of the corresponding entity buffer zone and return to step S14 until all virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities satisfy the spatial relationship.

[0043] S17. Use the optimal virtual 3D space polyhedron to physically cut the 3D geographic scene model to obtain multiple 3D geographic entity individual model files. Name and extract the 3D geographic entity individual model files according to the names of each entity element in the 2D geographic entity vector file.

[0044] In this embodiment, because the building / structure includes protruding structures such as eaves and cantilevered balconies, this invention extends the boundaries of the building / structure and facility entity patches outward to generate corresponding entity buffer boundaries. Spatial detection is then performed on the virtual 3D polyhedron formed based on these entity buffer boundaries to ensure that the complete structure of the building is contained within the negative half-space of the 3D polyhedron. This avoids escape points causing holes in the model structure during cutting, which would affect the overall effect. For scene models such as roads and water systems, spatial detection is not required because these scene models generally do not have the aforementioned protruding structural parts. Holes after cutting according to the 3D polyhedron are almost impossible to occur, and even if holes are accidentally created, they do not need to be modified if they do not affect the overall effect.

[0045] The hierarchical extraction method for the three-dimensional model of marine disaster-bearing bodies provided in this invention can effectively improve the executability of identification and judgment in the individualization step of the three-dimensional geographic scene by hierarchically encoding and naming each entity element in the two-dimensional geographic entity vector file. It accelerates the identification and judgment of two-dimensional geographic entities based on key field information, quickly locates the feature range of the element that needs to be established, effectively and accurately provides the cutting space range based on the virtual three-dimensional space polyhedron, and realizes the naming of individual elements of three-dimensional geographic entities according to the naming rules. Based on the multi-level classification logic of the elements, it quickly and automatically picks up the extraction objects, synchronously and automatically establishes folder organization, and efficiently completes the automatic output of the result files.

[0046] The hierarchical extraction method for three-dimensional models of marine disaster-bearing bodies provided in this invention can, in scenarios where ground features are precisely managed and analyzed, assign individual values ​​and process data for the model according to different application needs, such as traffic elements, water body elements, water conservancy elements, building elements, etc., and determine the management method of classifying and grading the results according to professional applications. It can achieve the goal of rapid hierarchical and classified management application by using advanced technical methods, thereby improving the usability and ease of use of data.

[0047] In this embodiment of the invention, step S12, which involves hierarchically encoding and naming each entity element in the two-dimensional geographic entity vector file, specifically includes the following steps (not shown in the accompanying drawings):

[0048] S121. Based on the natural classification attributes of each entity element in the two-dimensional geographic entity vector file, each entity element is classified into three levels. The first level of the three-level classification is divided into buildings / structures and facilities, water conservancy, water bodies and transportation according to geographic elements. According to the preset hierarchical classification logic rules, the three-level classification information is obtained by further subdividing each category included in the previous level classification in a fine-grained manner.

[0049] S122. Obtain the administrative region information, preset unit division information, model processing type, three-level classification information and sequence number information of each entity element in the two-dimensional geographic entity vector file, and encode each type of information to obtain the administrative region code, unit code, model processing type code, three-level classification code and sequence number code.

[0050] In a specific example, the three-level classification coding can be set according to the natural classification attributes of geographic entity elements. The three-level classification and coding names are as follows:

[0051] The primary classification of marine disaster-bearing bodies, based on the geographical elements they encompass, includes buildings and facilities (FW), water conservancy (SL), water bodies (ST), and transportation (JT). Secondary classifications are then established based on these primary classifications. Buildings and facilities (FW) specifically refer to houses; water conservancy (SL) specifically refers to canals, ditches, and reservoirs; water bodies (ST) specifically refer to rivers, lakes, and ponds; and transportation (JT) specifically refers to rail transit, urban roads, bridges, traffic junctions, and highways. Based on the secondary classification, a tertiary classification is established. Specifically, houses refer to ordinary houses (PTFW), stilted houses, stilted buildings (JKDJ), covered walkways (arcades), and floating buildings (LFPL); rivers are specifically surface rivers (DMHL); lakes and ponds are specifically lakes (HT) and ponds (CT); canals and ditches are specifically canals (YH) and surface ditches (DMQ); reservoirs are specifically water storage areas (XSQ); and rail transit specifically includes standard gauge railways (BZTL), narrow gauge railways (ZGTL), and subways. (DT), Maglev rail, Light rail (CFQG); Urban roads specifically include expressways (KSL), arterial roads (ZGL), secondary arterial roads (CGL), and local roads (ZL); Bridges specifically include railway bridges (TLQ), highway bridges (GLQ), combined road and rail bridges (GTLQ), grade-separated interchanges (LJQ), and other special-purpose bridges (QTQ); Traffic connection intersections specifically include roundabouts and intersections (LK); Highways specifically include national highways (GD), provincial highways (SD), county roads (XD), and other roads (other roads).

[0052] The logical relationship formula for element classification is as follows:

[0053] ;

[0054] ;

[0055] ;

[0056] ;

[0057] In the formula:

[0058] This represents all elements in the three-level classification of housing.

[0059] This represents all elements in the three-level classification of water bodies;

[0060] This represents all elements in the three-level classification of water resources.

[0061] This represents all elements in the three-level classification of transportation.

[0062] S123. Combine the coding data of each entity element in the order of administrative region code, unit code, model processing type code, three-level classification code and serial number code to generate the name of the corresponding entity element.

[0063] In this embodiment of the invention, the administrative region information, preset unit division information, model processing type information, three-level classification information, and sequence number information of each entity element in the two-dimensional geographic entity vector file are first obtained. Each type of information is then encoded to obtain the administrative region code, unit code, model processing type code, three-level classification code, and sequence number code. Specifically, the administrative region code is obtained by extracting spatial location. Unit codes are obtained by dividing the elements into units. The model processing type encoding is obtained through model processing methods. The element classification code is identified by recognizing the three-level classification of natural classification of two-dimensional geographic entities. Automatically create serial number codes .

[0064] Then, following the order of administrative region code, unit code, model processing type code, three-level classification code, and sequence number code, an element name field MC is created for each entity element in the two-dimensional geographic entity vector file, represented as follows:

[0065] ,

[0066] The coded data for each entity element are combined to automatically categorize and name the MC field of the element name. The naming coding rules are as follows: Figure 2 As shown.

[0067] In this embodiment of the invention, step S13, which involves extending the boundaries of building / structure and facility entity patches outward to generate corresponding entity buffer boundaries, specifically includes the following steps (not shown in the accompanying drawings):

[0068] S131. Identify the entity map boundaries corresponding to building / structure and facility entity elements in the two-dimensional geographic entity vector file, and divide the entity map boundaries corresponding to building / structure and facility entity elements into convex polygons and concave polygons.

[0069] S132. For a first entity feature whose entity patch boundary is a convex polygon, the coordinate points of each corresponding boundary of the convex polygon are extended outward according to a preset buffer distance to obtain the corresponding buffer boundary coordinate points. The entity buffer boundary of the corresponding first entity feature is obtained by connecting the coordinate points of each buffer boundary.

[0070] S133. For a second entity feature whose entity patch boundary is a concave polygon, the concave polygon is split into multiple convex sub-polygons. According to the preset buffer distance d, each coordinate point of the corresponding boundary of each convex sub-polygon is extended outward to obtain the corresponding buffer boundary coordinate point. The buffer boundary coordinate points are connected to obtain the sub-buffer boundary corresponding to each convex sub-polygon. After merging the sub-buffer boundaries of each convex sub-polygon, the effective contour boundary is extracted to obtain the entity buffer boundary of the corresponding second entity feature.

[0071] In this embodiment of the invention, the boundaries of building / structure and facility entity elements in two-dimensional geographic entity features are buffered outward at a fixed distance. The buffered buffers are then merged with the original building / structure and facility entity ranges to generate new entity buffer boundaries for building / structure and facility entities. A feature consists of multiple unconnected parts. A buffer boundary is generated separately for each building / structure and facility two-dimensional geographic entity feature, with overlapping buffers between adjacent features, each remaining independent. Specifically, the entity features corresponding to the building / structure and facility two-dimensional geographic entities are divided into convex polygons and concave polygons. A fixed-distance buffering method is used, and the boundary points of the building / structure and facility two-dimensional geographic entities are buffered... The buffer boundary of a 2D geographic entity is obtained by extending the buffer outward to point p, where the convex polygon 2D geographic entity satisfies the fixed-distance buffering method. This is achieved by extending the buffer boundary coordinates of each coordinate point on the corresponding boundary of the convex polygon outward. Connecting these buffer boundary coordinates yields the entity buffer boundary of the corresponding entity feature. For concave polygons, after buffering the concave portion of the 2D geographic entity, adjacent offset edges may self-intersect, resulting in the generated polygon containing invalid loops or holes. Alternatively, if the included angle between adjacent edges is too small, the arc at the vertex may cover other areas, forming a redundant structure. To address these issues, this invention splits the concave polygon into multiple convex sub-polygons, buffers each convex sub-polygon separately, merges the results, and retains the valid contour, ultimately generating the buffer boundary S of the 2D geographic entity. The buffering formula for point p of the buffer boundary S of the 2D geographic entity is as follows:

[0072] Point set:

[0073] ;

[0074] Edge objects:

[0075] ;

[0076] For each edge of the polygon Calculate the unit normal vector , buffering outwards at a fixed distance d.

[0077] Buffered point objects:

[0078] ;

[0079] Buffered objects:

[0080] ;

[0081] In the formula:

[0082] Points representing the boundaries of two-dimensional geographic entities;

[0083] represent The X and Y coordinates of the point;

[0084] n represents the number of points contained in the polygon after its sides are expanded;

[0085] The edge representing the boundary line of a two-dimensional geographic entity;

[0086] This is the unit normal vector of the boundary of a two-dimensional geographic entity.

[0087] Points representing the buffer boundaries of two-dimensional geographic entities;

[0088] An edge representing the boundary of a two-dimensional geographic entity buffer zone.

[0089] In this embodiment, n represents the number of points in the polygon, i represents any point, and i=0 means that the starting point is set to 0, and the last point of the closed polygon coincides with the starting point. When the starting point of the closed polygon is set to 0, the last point that is adjacent to the starting point but does not coincide with the starting point is n-1.

[0090] In this embodiment of the invention, the specific implementation of forming multiple virtual three-dimensional spatial polyhedra in step S14 includes:

[0091] Locating the spatial location of each entity element. Specifically, this refers to identifying each entity element based on the attribute information of two-dimensional geographic entity data, obtaining the spatial boundary coordinate information of two-dimensional geographic entities such as transportation, water conservancy, and water systems, as well as obtaining the boundary coordinate information of the entity buffer zone corresponding to the entity elements of buildings / structures and facilities, and locating the corresponding area in the three-dimensional geographic scene model obtained by oblique photography based on the obtained coordinate information;

[0092] Extrusion of individual entity elements. Specifically, this refers to extruding along the normal vector direction of a plane, using the entity buffer boundary of the building / structure and facility entities, as well as the entity patch boundary plane of other entity elements besides the building / structure and facility entities, as references, to construct a virtual three-dimensional polyhedron. The normal vector of the plane is a vector perpendicular to that plane. For a point on a two-dimensional vector plane... If the stretching distance along the normal vector direction is h, then the coordinates of the points on the corresponding virtual 3D polyhedron are... The formula is as follows:

[0093] The equation of the two-dimensional plane containing the two-dimensional geographic entity is:

[0094] ;

[0095] The normal vector of the plane is:

[0096] ;

[0097] Normalized normal vector:

[0098] ;

[0099] For any point on a two-dimensional plane Its three-dimensional coordinates are :

[0100] ;

[0101] in:

[0102] Ordinary three-dimensional vector;

[0103] Representative vector The modulus length;

[0104] It is the unit normal vector of a two-dimensional geographic entity plane;

[0105] A, B, C are the normal vectors of the plane. The component of the plane determines its orientation;

[0106] D is a constant term that determines the position of the plane.

[0107] In this embodiment of the invention, step S15, which involves spatial relationship detection between the virtual three-dimensional spatial polyhedron corresponding to the building / structure and facility entity and the three-dimensional geographic scene model, specifically includes the following steps: spatially overlaying the virtual three-dimensional spatial polyhedron corresponding to the building / structure and facility entity with the three-dimensional geographic scene model to analyze the spatial positional relationship between the vertices of the virtual three-dimensional spatial polyhedron corresponding to each building / structure and facility entity and the corresponding spatial location model element in the three-dimensional geographic scene model. The virtual three-dimensional spatial polyhedron is either a convex polyhedron or a concave polyhedron; if the building / structure and facility entity corresponds to… If the virtual 3D space polyhedron is a convex polyhedron, determine whether all points of the corresponding model element in the 3D geographic scene model are in the negative half-space of the convex polyhedron. If so, it is determined that the spatial relationship is satisfied; otherwise, it is determined that the spatial relationship is not satisfied. If the virtual 3D space polyhedron corresponding to the building / structure and facility entity is a concave polyhedron, determine whether all points of the corresponding model element in the 3D geographic scene model are in the negative half-space of the concave polyhedron and whether the edges do not intersect with the faces of the concave polyhedron. If so, it is determined that the spatial relationship is satisfied; if there are points in the positive half-space of the concave polyhedron or the edges intersect with the faces of the concave polyhedron, it is determined that the spatial relationship is not satisfied.

[0108] In this embodiment of the invention, the spatial relationship detection method specifically involves performing spatial overlay analysis on a virtual three-dimensional spatial polyhedron P corresponding to the building / structure and facility entity and a three-dimensional geographic scene model M to determine the spatial positional relationship between the vertices of the virtual three-dimensional spatial polyhedron and the three-dimensional geographic scene model. The virtual three-dimensional spatial polyhedron can be either convex or concave. Convex polyhedra require point inclusion detection, while concave polyhedra require point inclusion detection and edge / face overlap determination. Specifically, if the virtual three-dimensional spatial polyhedron P is convex, each point v corresponding to the model element in the three-dimensional geographic scene model M is traversed. For each face of a convex polyhedron Calculate the plane equation value of point v, and determine whether the obtained equation value is less than or equal to zero. If the equation value is less than or equal to zero, then all points of the current model element are in the negative half-space of all faces of the convex polyhedron, proving that the model element corresponding to the 3D geographic scene model M is inside the convex polyhedron and satisfies the spatial relationship. If the virtual 3D space polyhedron P is a concave polyhedron, iterate through each point v of the corresponding model element in the 3D geographic scene model. For each face of a concave polyhedron Calculate the plane equation value of v, determine whether the obtained equation value is less than or equal to zero, and traverse each edge e of the corresponding model element in the 3D geographic scene model for each face of the polyhedron. Determine the intersection of edges and faces. If the equation value is less than or equal to zero and the edges and faces do not intersect, then all points of the current model element are in the negative half space of the concave polyhedron and the edges do not intersect the faces of the concave polyhedron. The detection results are all in the negative half space, which proves that the model element corresponding to the 3D geographic scene model M is inside the concave polyhedron. The result is determined to satisfy the spatial relationship condition.

[0109] When determining whether a 3D geographic scene model M is completely located inside a virtual 3D space polyhedron P, v is set. Represents a vertex in a 3D geographic scene model.

[0110] If P is a convex polyhedron, the equations of all its faces are defined as follows: (If the normal vector points outwards), then the logical condition is:

[0111] ;

[0112] If P is a concave polyhedron, it is necessary to additionally check whether the edges and faces of the 3D geographic scene model M penetrate the surface of P:

[0113] .

[0114] In the formula:

[0115] The three-dimensional geographic scene model M is contained within the three-dimensional spatial polyhedron P.

[0116] This represents all points in the 3D geographic scene model M;

[0117] Represents all edges in the 3D geographic scene model M;

[0118] Represents all the faces in a three-dimensional polyhedron P;

[0119] Indicates "and";

[0120] This indicates that the edges of the 3D geographic scene model M do not intersect with the faces of the 3D spatial polyhedron P.

[0121] In this embodiment of the invention, step S16, which involves dynamically adjusting the boundary of the corresponding solid buffer zone for virtual three-dimensional spatial polyhedra that do not satisfy spatial relationships, specifically includes the following steps (not shown in the accompanying drawings):

[0122] S161. Label the spatial relationship detection results of the virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities. Virtual three-dimensional spatial polyhedra that meet the spatial relationship are labeled with a Boolean value of 1, and virtual three-dimensional spatial polyhedra that do not meet the spatial relationship are labeled with a Boolean value of 0.

[0123] In this embodiment, the steps include: detection result identification: if the virtual three-dimensional space polyhedron P is a convex polyhedron, and each point v in the three-dimensional geographic scene M... Within the polyhedron, prove that the 3D geographic scene model M is inside the virtual 3D space polyhedron P. Determine that this result satisfies the spatial relationship condition. The result value is represented by a Boolean value of 1. If the 3D geographic scene Mz contains a point v... Escape indicates failure to meet spatial conditions, and the result value is represented by the Boolean value 0. If the 3D spatial polyhedron P is a concave polyhedron, and each point v in the 3D geographic scene M... Within a 3D polyhedron, and where each edge e of the 3D geographic scene M does not intersect with the 3D polyhedron, the result is deemed to satisfy the spatial relationship condition, and the result value is represented by a Boolean value of 1; if the point of the 3D geographic scene M... If the detection result shows vertex escape or edge / face penetration, the result is considered not to meet the spatial relationship condition, and the result value is represented by a Boolean value of 0. Detection result annotation: Detection results with a Boolean value of 0 are annotated.

[0124] Assuming the test results are used The logic conditions for triggering detection and location annotation are as follows:

[0125] If P is a convex polyhedron:

[0126] ;

[0127] If P is a concave polyhedron:

[0128] ;

[0129] In the formula:

[0130] The line represents the intersection of a line and a surface;

[0131] The line represents a plane that does not intersect.

[0132] Represents the total number of points;

[0133] This means that at least one point exists;

[0134] Represents the total number of edges;

[0135] This means that at least one edge exists;

[0136] Represents the full range of surfaces;

[0137] This means that at least one face exists.

[0138] S162. Take the virtual 3D space polyhedron with the relationship detection result marked as 0 as the target virtual 3D space polyhedron, and calculate the maximum penetration distance of the target virtual 3D space polyhedron. The maximum penetration distance is the vertical distance from the point in the corresponding model element located outside the current target virtual 3D space polyhedron to the current target virtual 3D space polyhedron.

[0139] S163. Obtain the entity buffer boundary vector data corresponding to the target virtual three-dimensional space polyhedron, determine the optimal buffer distance based on the maximum penetration distance, and adjust the current entity buffer boundary based on the optimal buffer distance.

[0140] In this embodiment, for areas where the spatial relationship detection between the 3D geographic scene and the 3D spatial polyhedron model does not meet the spatial conditions, the detection result value is 0. The 2D geographic entity buffer boundary vector data of the buildings / structures and facilities involved in the virtual 3D spatial polyhedron are then collected. The optimal buffer distance is determined by dynamically adjusting the buffer distance based on the maximum penetration distance in the detection results. To accelerate convergence; perform space checks in the critical loop step: re-execute the outer buffer boundary expansion according to the above-described method of establishing an outer buffer. The process involves several key steps: forming new buffer boundaries for building / structure and facility entities, reconstructing 3D spatial polyhedra, re-detecting the 3D geographic scene and 3D spatial polyhedra, and re-annotating the detection results. Through these iterations, combined with dynamic distance adjustment and strict convergence conditions, the process ensures that the 3D scene model is ultimately fully contained. The detection results for the spatial relationships of the 3D geographic scene and the 3D spatial polyhedra are both 1, and the process stops when the spatial conditions are met. This process forms a 2D geographic entity buffer boundary that completely contains the projection range of the 3D geographic scene.

[0141] Vertex sequence: ;

[0142] Outward expansion distance Edge objects: ;

[0143] Outer vertex coordinates: ,

[0144] In the formula:

[0145] Points representing the boundaries of a two-dimensional geographic entity buffer zone;

[0146] An edge representing the boundary of a two-dimensional geographic entity buffer zone;

[0147] The buffer distance is dynamically adjusted to represent the maximum penetration distance.

[0148] The point represents the boundary of the new two-dimensional geographic entity buffer after the loop.

[0149] In this embodiment of the invention, step S17, which involves physically cutting the 3D geographic scene model using the optimal virtual 3D spatial polyhedron, specifically includes: using the optimal virtual 3D spatial polyhedron as a spatial cutting reference, stretching the bottom face of the optimal virtual 3D spatial polyhedron downwards along the Z-axis, calculating the intersection line between the optimal virtual 3D spatial polyhedron and the 3D geographic scene model, using the intersection line as a cutting line to perform Boolean operations on the 3D geographic scene model to achieve physical spatial cutting, and outputting a 3D geographic entity single-unit model file.

[0150] The automatic segmentation method for 3D geographic scenes in this embodiment includes the following steps: Determining the cutting reference object: using the entity buffer boundary range S of the final building / structure and facility entities and the entity patch boundaries of other entity elements besides the building / structure and facility entities as the input range, and using the corresponding virtual 3D spatial polyhedron P within this range as the spatial cutting reference; Performing 3D geographic scene model cutting: stretching the bottom face of the 3D spatial polyhedron P downwards along the Z-axis, calculating the intersection line between the 3D spatial polyhedron P and the 3D geographic scene M as the cutting line, performing Boolean operations on the 3D geographic scene M model to achieve physical spatial cutting; Outputting a 3D geographic entity individualized model file. : The single-unit model located inside the cutting range line According to the file naming rules, the three-level MC fields in the two-dimensional geographic entity buffer boundary attribute name field are classified and named as follows: buildings and facilities (FW), water bodies (ST), water conservancy (SL), and transportation (JT). After cutting, the individual models are extracted and stored in a new folder, including the three-dimensional scene models located outside the cutting range. The files will still be stored according to their original file names and organization.

[0151] Cutting logic condition formula:

[0152] ;

[0153] In the formula, v is the vertex of M:

[0154] ;

[0155] Vertex in the formula The condition for belonging to P is:

[0156] ;

[0157] The file is saved based on the cutting results. The specific saving logic is as follows:

[0158] ;

[0159] In the formula:

[0160] This represents a single-unit model located inside the cutting boundary line;

[0161] This represents a single-unit model located outside the cutting boundary line;

[0162] The lowest point on the Z-axis represents P;

[0163] This represents the highest point of P on the Z-axis;

[0164] S represents the spatial extent of a two-dimensional geographic entity boundary or buffer boundary.

[0165] D represents the stored data;

[0166] F represents the name of the data;

[0167] MC represents the element name, which is named according to the naming rules.

[0168] Represents the name of an element in the original document.

[0169] In this embodiment of the invention, step S17, which involves naming and hierarchically extracting the three-dimensional geographic entity individual model files according to the names of each entity element in the two-dimensional geographic entity vector file, specifically includes the following steps: obtaining the three-level classification codes included in the names of each entity element; naming the corresponding three-dimensional geographic entity individual model files according to the three-level classification codes of each entity element; extracting the key field information of the three-level classification contained in the name of each three-dimensional geographic entity individual model file; establishing a hierarchical folder structure according to the organizational structure of the three-level classification and the key field information of each level of classification in the three-level classification; and extracting the three-dimensional geographic entity individual model files located within the cutting range to the corresponding level folders according to the names of the three-dimensional geographic entity individual model files, so as to ensure that the organizational structure of the individual files remains unchanged.

[0170] This invention enables automatic classification and storage of 3D geographic entity individual model files according to a folder organization structure. Specifically, it identifies the three-level classification feature fields of the individual model: automatically segmented according to the above steps. After naming the individual 3D models according to the naming rules, the model file names contain key field information for the three-level classification; a logical attribution judgment of the name hierarchy is performed: based on the key field information of the three-level classification and the logical attribution conditions of the corresponding first-level classification names; corresponding hierarchical folders are automatically created: first-level folders are created according to the first-level classifications of Buildings and Facilities (FW), Water Bodies (ST), Water Conservancy (SL), and Transportation (JT), and second-level and third-level folders are created according to the fine-grained division structure to form a folder structure; the individual 3D geographic entities are automatically extracted: the naming rules are executed to... After the model is classified into three levels, it is automatically and quickly extracted into the corresponding hierarchical folders, while ensuring... The organizational structure of the individual files remains unchanged, enabling rapid identification and storage of the individualized results. The 3D scene model ensures that the original file organization structure and naming remain unchanged. and To jointly form the final deliverables document The process has ended.

[0171] The hierarchical extraction method for the three-dimensional model of marine disaster-bearing bodies in this embodiment of the invention can formulate element name coding rules based on the hierarchical classification logic rules for creating the model. Based on the feature field information of each level in the coding rules, it can automatically classify and code the names of two-dimensional geographic entity elements. It can separately identify the vector boundaries of two-dimensional geographic entities such as transportation, water bodies, and water conservancy, and establish buffer boundaries for buildings / structures and facilities. Based on the element class coding of buildings (structures) and facilities in the attribute fields of the two-dimensional geographic entities, it can identify the spatial coordinate information of the boundary points of the two-dimensional geographic entity patches of buildings (structures) and facilities. Based on the spatial coordinates of the boundary points of the two-dimensional geographic entity patches of buildings (structures) and facilities, it can buffer a certain area outward to lock the spatial buffer boundary, generating two-dimensional... 3D geographic entity buffer zone boundary; Establish 3D spatial polyhedrons for 2D geographic entity vector boundaries and buffer zone boundaries: Based on the boundaries, stretch in the positive and negative directions of the Z-axis to form 3D spatial polyhedrons; Spatial relationship detection: Overlay the 3D spatial polyhedrons corresponding to buildings / structures and facilities with the 3D geographic scene model to determine spatial relationships, obtaining the conclusion of whether the 3D geographic scene model is in the negative half-space of the 3D spatial polyhedron. If all points in the 3D scene model are in the negative half-space of the convex polyhedron, it is determined that the condition is met; if there are points in the positive half-space, it is determined that the condition is not met; if all points in the 3D scene model are in the negative half-space of the concave polyhedron and their edges do not intersect with the faces of the concave polyhedron, it is determined that the condition is met. If a point in the 3D scene model intersects with a face of a 3D concave polyhedron, the result is considered as not meeting the condition. The detection result identification and annotation process involves identifying and locating the detection result values ​​that do not meet the condition. The automatic adjustment of the 2D geographic entity buffer boundary involves identifying the optimal buffer distance for 2D geographic entities in the labeled area, reducing the number of iterations, and then repeatedly creating new 2D geographic entity buffer boundaries, generating new 3D polyhedra, performing 3D polyhedron and 3D geographic scene space detection, and identifying and annotating detection results until the spatial detection result values ​​meet the condition. The loop then stops, and the 2D geographic entity buffer boundary that meets the condition is obtained. Virtual 3D spatial polyhedron; Automatic 3D scene model segmentation: The virtual 3D spatial polyhedron is stretched downwards by a certain distance, and the intersection cutting line between the 3D spatial polyhedron and the 3D geographic scene is identified and the cutting is performed. This achieves the individualization of 3D geographic entity elements within the cutting area, while the 3D geographic scene model outside the cutting line remains unchanged from the original model. Automatic establishment of output file organization structure: Based on the name coding rules, the key third-level classification feature fields of the individualized model name are identified. Based on the logical affiliation relationship between the third-level classification and the first-level classification, hierarchical classification folders are automatically created and the individualized models of the third-level classification are extracted and collected into their respective hierarchical classification folders. This completes the rapid hierarchical management process of extracting individualized 3D geographic entities of marine disaster prevention and mitigation bodies.

[0172] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the described order of actions, because according to the embodiments of the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to the embodiments of the present invention.

[0173] Another embodiment of the present invention provides a hierarchical extraction system for a three-dimensional model of a marine disaster-bearing body, the system comprising a functional module for implementing the hierarchical extraction method for a three-dimensional model of a marine disaster-bearing body as described in any of the preceding embodiments. Figure 3 The diagram schematically illustrates the structural block diagram of a hierarchical extraction system for a three-dimensional model of a marine disaster-bearing body, according to another embodiment of the present invention. (Refer to...) Figure 3 The hierarchical extraction system for the three-dimensional model of marine disaster-bearing bodies in this embodiment specifically includes a data acquisition module 301, a naming module 302, a boundary buffer module 303, a spatial polyhedron generation module 304, a spatial relationship detection module 305, a boundary adjustment module 306, and a single-unit model extraction module 307, wherein:

[0174] Data acquisition module 301 is used to acquire a three-dimensional geographic scene model and a two-dimensional geographic entity vector file of the marine storm surge area;

[0175] The naming module 302 is used to hierarchically encode and name each entity element in the two-dimensional geographic entity vector file.

[0176] Boundary buffer module 303 is used to identify each entity element and its corresponding entity patch boundary according to the name of the entity element, and to extend the building / structure and facility entity patch boundary outward to generate the corresponding entity buffer boundary;

[0177] The spatial polyhedron generation module 304 is used to locate the corresponding regional boundaries in the three-dimensional geographic scene model based on the entity buffer boundaries of building / structure and facility entities and the entity patch boundaries of other entity elements besides building / structure and facility entities, and to stretch each regional boundary in the positive and negative directions of the Z-axis to form multiple virtual three-dimensional spatial polyhedra.

[0178] The spatial relationship detection module 305 is used to perform spatial relationship detection on the virtual three-dimensional spatial polyhedrons corresponding to the building / structure and facility entities and the three-dimensional geographic scene model, so as to determine whether the building / structure and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional spatial polyhedrons of the corresponding spatial locations. If so, it is determined that the corresponding virtual three-dimensional spatial polyhedrons satisfy the spatial relationship; otherwise, the virtual three-dimensional spatial polyhedrons do not satisfy the spatial relationship.

[0179] The boundary adjustment module 306 is used to dynamically adjust the boundary of the corresponding entity buffer for virtual three-dimensional spatial polyhedra that do not satisfy the spatial relationship, and return to the spatial polyhedron generation module to re-execute the spatial polyhedron generation step until the spatial relationship detection module detects that the current virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities all satisfy the spatial relationship, thus obtaining the optimal virtual three-dimensional spatial polyhedron.

[0180] The single-entity model extraction module 307 is used to physically cut the three-dimensional geographic scene model with the optimal virtual three-dimensional space polyhedron to obtain multiple three-dimensional geographic entity single-entity model files, and to name and extract the three-dimensional geographic entity single-entity model files according to the names of each entity element in the two-dimensional geographic entity vector file.

[0181] As the system implementation is basically similar to the method implementation, the description is relatively simple, and relevant parts can be found in the description of the method implementation.

[0182] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0183] In addition, another embodiment of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor; when the computer program is executed by the processor, it implements the steps of the graded extraction method for the three-dimensional model of marine disaster-bearing bodies as described above.

[0184] In addition, another embodiment of the present invention provides a computer program product, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the graded extraction method for the three-dimensional model of marine disaster prevention and mitigation bodies as described above.

[0185] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, any of the claimed embodiments can be used in any combination.

[0186] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hierarchical extraction method for a three-dimensional model of a marine disaster-bearing body, characterized in that, The method includes: S11. Obtain the 3D geographic scene model and 2D geographic entity vector file of the marine storm surge area; S12. Hierarchical coding and naming of each entity element in the two-dimensional geographic entity vector file; S13. Identify each entity element and its corresponding entity patch boundary according to the name of the entity element, and extend the boundaries of building / structure and facility entity patches outward to generate corresponding entity buffer boundaries. S14. Based on the entity buffer boundaries of buildings / structures and facilities, as well as the entity patch boundaries of other entity elements besides buildings / structures and facilities, locate the corresponding region boundaries in the three-dimensional geographic scene model, and stretch each region boundary in the positive and negative directions of the Z-axis to form multiple virtual three-dimensional space polyhedra. S15. Perform spatial relationship detection on the virtual three-dimensional spatial polyhedron corresponding to the building / structure and facility entity and the three-dimensional geographic scene model, so as to determine whether the building / structure and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional spatial polyhedron at the corresponding spatial location. If so, determine that the corresponding virtual three-dimensional spatial polyhedron satisfies the spatial relationship and obtain the optimal virtual three-dimensional spatial polyhedron; otherwise, proceed to step S16. S16. For virtual three-dimensional spatial polyhedra that do not satisfy the spatial relationship, dynamically adjust the boundary of the corresponding entity buffer zone and return to step S14 until all virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities satisfy the spatial relationship. S17. Use the optimal virtual 3D space polyhedron to physically cut the 3D geographic scene model to obtain multiple 3D geographic entity individual model files. Name and extract the 3D geographic entity individual model files according to the names of each entity element in the 2D geographic entity vector file.

2. The method according to claim 1, characterized in that, Hierarchical coding and naming of each entity feature in a two-dimensional geographic entity vector file, including: Based on the natural classification attributes of each entity element in the two-dimensional geographic entity vector file, each entity element is classified into three levels. The first level of the three-level classification is divided into buildings / structures and facilities, water conservancy, water bodies and transportation according to geographic elements. According to the preset hierarchical classification logic rules, the three-level classification information is obtained by further subdividing each category included in the previous level classification. The administrative region information, preset unit division information, model processing type, three-level classification information and sequence number information of each entity element in the two-dimensional geographic entity vector file are obtained, and each type of information is encoded to obtain the administrative region code, unit code, model processing type code, three-level classification code and sequence number code. The coding data of each entity element are combined in the order of administrative region code, unit code, model processing type code, three-level classification code, and serial number code to generate the name of the corresponding entity element.

3. The method according to claim 1, characterized in that, The boundaries of building / structure and facility entity maps are extended outwards to generate corresponding entity buffer boundaries, including: Identify the entity map boundaries corresponding to building / structure and facility entity elements in two-dimensional geographic entity vector files, and divide the entity map boundaries corresponding to building / structure and facility entity elements into convex polygons and concave polygons. For a first entity feature whose entity patch boundary is a convex polygon, the coordinate points of each corresponding boundary of the convex polygon are extended outward according to a preset buffer distance to obtain the corresponding buffer boundary coordinate points. The entity buffer boundary of the corresponding first entity feature is obtained by connecting the coordinate points of each buffer boundary. For a second entity feature whose entity patch boundary is a concave polygon, the concave polygon is split into multiple convex sub-polygons. According to the preset buffer distance d, the coordinate points of each corresponding boundary of each convex sub-polygon are extended outward to obtain the corresponding buffer boundary coordinate points. The coordinate points of each buffer boundary are connected to obtain the sub-buffer boundary corresponding to each convex sub-polygon. After merging the sub-buffer boundaries of each convex sub-polygon, the effective contour boundary is extracted to obtain the entity buffer boundary of the corresponding second entity feature.

4. The method according to claim 1, characterized in that, Spatial relationship detection is performed on the virtual 3D spatial polyhedron corresponding to the building / structure and facility entities and the 3D geographic scene model, including: The virtual three-dimensional spatial polyhedrons corresponding to the building / structure and facility entities are spatially superimposed with the three-dimensional geographic scene model to analyze the spatial positional relationship between the vertices of the model elements at the corresponding spatial positions in the three-dimensional geographic scene model and the virtual three-dimensional spatial polyhedrons corresponding to each building / structure and facility entity. The virtual three-dimensional spatial polyhedrons are convex polyhedra and concave polyhedra. If the virtual three-dimensional space polyhedron corresponding to the building / structure and facility entity is a convex polyhedron, determine whether all points of the corresponding model element in the three-dimensional geographic scene model are in the negative half space of the convex polyhedron. If so, it is determined that the spatial relationship is satisfied; otherwise, it is determined that the spatial relationship is not satisfied. If the virtual 3D spatial polyhedron corresponding to the building / structure and facility entity is a concave polyhedron, determine whether all points of the corresponding model element in the 3D geographic scene model are in the negative half space of the concave polyhedron and whether the edges do not intersect with the faces of the concave polyhedron. If so, it is determined that the spatial relationship is satisfied. If there are points in the positive half space of the concave polyhedron or the edges intersect with the faces of the concave polyhedron, it is determined that the spatial relationship is not satisfied.

5. The method according to claim 4, characterized in that, Determine whether all points of a corresponding model element in a 3D geographic scene model lie in the negative half-space of a convex polyhedron, including: Traverse each point v corresponding to a model element in the 3D geographic scene model. For each face of a convex polyhedron Calculate the plane equation value of point v, and determine whether the obtained equation value is less than or equal to zero. If the equation value is less than or equal to zero, then all points of the current model element are in the negative half space of the convex polyhedron. Determine whether all points of a corresponding model element in a 3D geographic scene model are located in the negative half-space of a concave polyhedron and whether the edges do not intersect the faces of the concave polyhedron, including: Traverse each point v corresponding to a model element in the 3D geographic scene model. For each face of a concave polyhedron Calculate the plane equation value of v, determine whether the obtained equation value is less than or equal to zero, and traverse each edge e of the corresponding model element in the 3D geographic scene model for each face of the polyhedron. Determine the intersection of edges and faces. If the equation value is less than or equal to zero and the edges and faces do not intersect, then all points of the current model elements are in the negative half-space of the concave polyhedron and the edges do not intersect the faces of the concave polyhedron.

6. The method according to claim 1, characterized in that, For virtual 3D polyhedra that do not satisfy spatial relationships, the boundaries of their corresponding entity buffers are dynamically adjusted, including: The spatial relationship detection results of virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities are labeled. Virtual three-dimensional spatial polyhedra that meet the spatial relationship are labeled with a Boolean value of 1, and virtual three-dimensional spatial polyhedra that do not meet the spatial relationship are labeled with a Boolean value of 0. The virtual 3D space polyhedron with a relationship detection result of 0 is taken as the target virtual 3D space polyhedron. The maximum penetration distance of the target virtual 3D space polyhedron is calculated. The maximum penetration distance is the vertical distance from the point in the corresponding model element located outside the current target virtual 3D space polyhedron to the current virtual 3D space polyhedron. Obtain the entity buffer boundary vector data corresponding to the target virtual 3D polyhedron, determine the optimal buffer distance based on the maximum penetration distance, and adjust the current entity buffer boundary based on the optimal buffer distance.

7. The method according to claim 2, characterized in that, Physical spatial segmentation of a 3D geographic scene model using an optimal virtual 3D spatial polyhedron includes: Using the optimal virtual 3D space polyhedron as a spatial cutting reference, the bottom face of the optimal virtual 3D space polyhedron is stretched downward along the Z-axis. The intersection line between the optimal virtual 3D space polyhedron and the 3D geographic scene model is calculated. The intersection line is used as the cutting line to perform Boolean operations on the 3D geographic scene model to achieve physical spatial cutting, and outputs a 3D geographic entity single-unit model file.

8. The method according to claim 7, characterized in that, The 3D geographic entity individual model file is named and hierarchically extracted according to the names of each entity feature in the 2D geographic entity vector file, including: Obtain the three-level classification codes included in the names of each entity element; Name the corresponding 3D geographic entity individual model file according to the three-level classification code of each entity element; Extract the key field information of the three-level classification contained in the name of each 3D geographic entity individual model file; Establish a hierarchical folder structure based on the organizational structure of the three-level classification and the key field information of each level of the three-level classification; Based on the name of the individual 3D geographic entity model file, extract the individual 3D geographic entity model files located within the cutting area to the corresponding level of folder to ensure that the organizational structure of the individual files remains unchanged.

9. A hierarchical extraction system for a three-dimensional model of a marine disaster-bearing body, characterized in that, The system includes: The data acquisition module is used to acquire three-dimensional geographic scene models and two-dimensional geographic entity vector files of the marine storm surge area; The naming module is used to hierarchically encode and name the various entity elements in a two-dimensional geographic entity vector file. The boundary buffer module is used to identify each entity element and its corresponding entity patch boundary based on the name of the entity element, and to extend the boundaries of building / structure and facility entity patches outward to generate the corresponding entity buffer boundary. The spatial polyhedron generation module is used to locate the corresponding region boundaries in the 3D geographic scene model based on the entity buffer boundaries of building / structure and facility entities and the entity patch boundaries of other entity elements besides building / structure and facility entities, and to stretch each region boundary in the positive and negative directions of the Z-axis to form multiple virtual 3D spatial polyhedra. The spatial relationship detection module is used to perform spatial relationship detection on the virtual three-dimensional spatial polyhedrons corresponding to the building / structure and facility entities and the three-dimensional geographic scene model, so as to determine whether the building / structure and facility model elements in the three-dimensional geographic scene model are all located in the virtual three-dimensional spatial polyhedrons of the corresponding spatial locations. If so, it is determined that the corresponding virtual three-dimensional spatial polyhedrons satisfy the spatial relationship; otherwise, the virtual three-dimensional spatial polyhedrons do not satisfy the spatial relationship. The boundary adjustment module is used to dynamically adjust the boundary of the corresponding entity buffer for virtual three-dimensional spatial polyhedra that do not satisfy the spatial relationship, and return to the spatial polyhedron generation module to re-execute the spatial polyhedron generation step until the spatial relationship detection module detects that the current virtual three-dimensional spatial polyhedra corresponding to the building / structure and facility entities all satisfy the spatial relationship, thus obtaining the optimal virtual three-dimensional spatial polyhedron. The single-entity model extraction module is used to physically cut the 3D geographic scene model using the optimal virtual 3D space polyhedron to obtain multiple 3D geographic entity single-entity model files. The 3D geographic entity single-entity model files are named and extracted hierarchically according to the names of each entity element in the 2D geographic entity vector file.

10. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor; when executed by the processor, the computer program implements the steps of the method as described in any one of claims 1-8.

11. A computer program product, characterized in that, The computer program product stores a computer program that, when executed by a processor, implements the steps of the method as described in any one of claims 1-8.

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