Web vectorization hierarchical display method based on electronic sea chart sheet

Abstract

The invention discloses a web vectorization hierarchical display method based on an electronic sea chart sheet, and relates to the technical field of sea chart display, and the method comprises the steps: carrying out the characterization extraction processing of a sea chart three-dimensional model, and obtaining a sea chart sub-model; obtaining connection models of the sea chart sub-models and connection preference of each connection model; performing layering processing on the three-dimensional sea chart model based on the real-time analysis elements, and displaying the three-dimensional sea chart model after layering processing in a web; the method is used for solving the problems that in an existing web display method for the electronic sea chart sheet, vectorization layering cannot be carried out on an electronic sea chart displayed in a web according to elements needed by a user, so that when the user browses sea chart data in the web, needed data cannot be obtained in a targeted mode on the basis of the requirements of the user, and the user experience is poor. And the analysis speed of the user on the chart data is reduced.

Description

Technical Field

[0001] This invention relates to the field of nautical chart display technology, specifically a web-based vectorized layered display method based on electronic nautical chart sheets. Background Technology

[0002] The map sheet of an electronic nautical chart refers to the geographical area covered by the chart, defined by its inner boundary, that is, the actual geographical information area enclosed by lines of latitude and longitude. Although electronic nautical charts are presented in digital form, their map sheet concept differs from that of traditional nautical charts. Figure 1 Both define the geographical scope through the inner outline; vectorization refers to the process of converting images or data into a vector format based on mathematical algorithms. Vectorized layered display is a technique that decomposes complex images or data into editable vector elements according to a hierarchical structure.

[0003] Existing methods for web display of electronic nautical chart sheets typically generate tile charts based on the corresponding data files of the electronic chart. The client then obtains the requested tile charts and transmits them to the server for web display. While this improved method can increase browsing speed, it only enhances the display speed of the electronic chart and cannot perform vectorized layering of the displayed electronic chart based on the user's required elements. This results in users being unable to obtain the specific data they need when browsing web-based chart data, thus slowing down the analysis of the chart data. For example, patent application CN118503567A discloses... A web browser-based method for quickly displaying electronic nautical charts is proposed. This method deploys the electronic nautical chart software on a server, allowing users to access the latest chart data and functions through a browser. This offers significant convenience compared to client-based methods. However, other improvements to the web display of electronic nautical chart sheets typically address conventional chart processing methods. These methods still fail to vectorize and layer the electronic nautical charts displayed on the web according to the user's required elements. Consequently, users cannot obtain the specific data they need when browsing chart data on the web, reducing the speed of chart data analysis. Therefore, it is necessary to improve existing methods for web display of electronic nautical chart sheets. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in the prior art by proposing a web vectorized layered display method based on electronic nautical chart sheets. This method addresses the issue that existing web display methods for electronic nautical chart sheets cannot perform vectorized layering of the electronic nautical charts displayed on the web according to the elements required by the user. As a result, when users browse nautical chart data on the web, they cannot obtain the data they need based on their specific requirements, which reduces the speed of users' analysis of nautical chart data.

[0005] To achieve the above objectives, this application provides a web-based vectorized layered display method based on electronic nautical chart sheets, comprising the following steps:

[0006] Obtain the 3D model corresponding to the electronic nautical chart sheet and denote it as the sea. Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The dimensional model is subjected to feature extraction processing, and the corresponding nautical chart sub-model for each element is obtained based on the result of feature extraction processing. The elements include geographic features, navigation features and hydrological features.

[0007] Analyze all chart sub-models and obtain the connection model for each chart sub-model based on the analysis results; analyze the connection model based on the chart sub-models and obtain the connection preference for each connection model based on the analysis results;

[0008] Elements invoked when using electronic nautical chart sheets are denoted as real-time analysis elements, and the corresponding chart sub-models are denoted as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the nautical charts are analyzed. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 The dimensional model is displayed on the web.

[0009] Furthermore, based on the elements contained in the electronic nautical chart sheet, the sea... Figure 3 The dimensional model undergoes feature extraction processing, and based on the results of feature extraction, the corresponding nautical chart sub-model for each element is obtained, including:

[0010] Establish a spatial coordinate system with all axes in meters (m) as the unit, and denote it as a sea level. Figure 3 A 3D coordinate system was established; data corresponding to the electronic nautical chart sheets were read and elevation information was extracted. Interpolation and gridding were used to convert the 2D data of the electronic nautical chart sheets into 3D terrain data, and 3D modeling techniques were used to model the terrain at sea. Figure 3 Obtain the 3D model corresponding to the electronic nautical chart sheet in a 3D coordinate system, denoted as nautical map sheet. Figure 3 3D model;

[0011] Based on the geographic, navigational, and hydrological elements contained in the electronic nautical chart, a geographic database, a navigational database, and a hydrological database are established to store the data corresponding to the geographic, navigational, and hydrological elements in the electronic nautical chart.

[0012] The sea is analyzed based on data from geographic databases, navigation databases, and hydrological databases respectively. Figure 3 The dimensional model is subjected to feature extraction processing, and the corresponding nautical chart sub-models for geographic features, navigation features, and hydrological features are obtained based on the processing results.

[0013] Furthermore, the feature extraction process includes:

[0014] For any element among geographic, navigational, and hydrological elements: the data corresponding to the element in the electronic nautical chart sheet is recorded as element data, and the labeled objects corresponding to the element data in the electronic nautical chart sheet are recorded as element labels; in the sea Figure 3 Mark the positions of all element markers in the 3D coordinate system;

[0015] Based on GeoServer, vector tiles corresponding to the electronic nautical chart sheet are obtained. When generating vector tiles, the vector tiles corresponding to each element marker generated from the electronic nautical chart sheet are obtained based on the position data of the element markers of all elements, and are recorded as the marker tiles of the element markers.

[0016] Furthermore, the feature extraction process also includes:

[0017] For any one of the geographic, navigational, and hydrological elements: acquire the data of the electronic chart sheet contained in each labeled tile, and record it as the chart tile data of the labeled tile; in the sea Figure 3 The model corresponding to the nautical chart tile data is obtained from the dimensional model and denoted as the nautical chart tile model;

[0018] Place the nautical chart tile models corresponding to all the labeled tiles of the element in the same blank sea. Figure 3 Within a 3D coordinate system, and at this time the sea Figure 3 A three-dimensional model in a 3D coordinate system is denoted as an element-based chart sub-model;

[0019] Obtain the corresponding nautical chart sub-models for geographic features, navigation features, and hydrological features respectively.

[0020] Furthermore, all chart sub-models are analyzed, and the connection model for each chart sub-model is obtained based on the analysis results; the connection model is analyzed based on the chart sub-models, and the connection preference for each connection model is obtained based on the analysis results, including:

[0021] For any two elements, their corresponding chart submodels α and β are placed in the same empty sea. Figure 3 In a 3D coordinate system, the model in which the chart sub-model α and the chart sub-model β coincide is denoted as the connecting model;

[0022] For chart submodel α or chart submodel β: the corresponding chart slice models are denoted as chart slice model HQ1 to chart slice model HQ, respectively. r Where r is the number of chart tile models corresponding to the chart sub-model; for any chart tile model HQt When the nautical chart slice model HQ t When there is an overlapping area with the connection model, the nautical chart slice model HQ will be used. t The region that overlaps with the connecting model is denoted as the slice overlap model; the volume of the slice overlap model is denoted as v, and the number of element labels corresponding to the elements of the nautical chart sub-model contained in the slice overlap model is denoted as u, where t is a positive integer less than or equal to r and greater than or equal to 1.

[0023] Furthermore, the analysis of the connectivity models based on the chart sub-model, and the acquisition of connectivity preferences for each connectivity model based on the analysis results, also includes:

[0024] When the nautical chart slice model HQ t When there is no overlapping area with the connection model, the nautical chart slice model HQ is used. t This is denoted as an unrelated model; the value of r divided by the number of unrelated models in all nautical chart slice models is denoted as the unrelated proportion.

[0025] Establish a Cartesian coordinate system, denoted as the preference comparison coordinate system, where the X-axis and Y-axis are constant axes. In the preference scale coordinate system, establish three rays with the origin as the endpoint, denoted as γ1, γ2, and γ3 respectively. The acute angle formed by γ1 and γ2 at the origin is 60°, the acute angle formed by γ1 and γ3 at the origin is 60°, and γ2 and γ3 do not coincide.

[0026] Furthermore, the analysis of the connectivity models based on the chart sub-model, and the acquisition of connectivity preferences for each connectivity model based on the analysis results, also includes:

[0027] In γ1, a point with a distance of V from the origin is obtained and denoted as a volume point. In γ2, a point with a distance of U from the origin is obtained and denoted as a coincidence quantity point. In γ3, a point with a distance of no correlation scale from the origin is obtained and denoted as a scale point. Here, V is the sum of v corresponding to all chart tile models that are not denoted as no correlation models, and U is the sum of u corresponding to all chart tile models that are not denoted as no correlation models.

[0028] The area of ​​the triangle formed by the volume point, the number of overlapping points, and the proportion point is recorded as the preference value; the preference values ​​corresponding to the chart sub-model α and the chart sub-model β are obtained, and the chart sub-model with the largest preference value is recorded as the connection preference of the connection model;

[0029] Obtain the connection models between the chart sub-models corresponding to all elements, as well as the connection preferences of each connection model.

[0030] Furthermore, based on the hierarchical model and the connection preferences of the corresponding connection model, the sea... Figure 3The 3D model is processed into layers, and the resulting sea Figure 3 Dimensional models displayed on the web include:

[0031] Jianghai Figure 3 Import the dimensional model into the web for browsing; when using electronic nautical chart sheets, the elements called in the electronic nautical chart sheets will be recorded as real-time analysis elements, and the nautical chart sub-models corresponding to the real-time analysis elements will be recorded as hierarchical models;

[0032] Obtain all connecting models corresponding to the hierarchical model and record them as models to be added; for any model to be added: when the connecting preference of the model to be added is a hierarchical model, record the model to be added as a same-layer application model; when the connecting preference of the model to be added is not a hierarchical model, record the model to be added as a different-layer application model.

[0033] sea ​​in the web Figure 3 The dimensional model is processed in layers.

[0034] Furthermore, the hierarchical processing includes a primary hierarchical level and secondary hierarchical levels. The primary hierarchical level includes:

[0035] When a peer-to-peer application model exists, the web will be in the middle. Figure 3 Same-layer application models within a dimensional model and hierarchical models from the sea Figure 3 The dimensional model is stripped and recorded as the calling application model; when no application model exists in the same layer, the web layer is... Figure 3 Hierarchical models within a dimensional model from the sea Figure 3 The model is stripped from the dimensional model, where the application model is the model corresponding to the element called by the user.

[0036] Furthermore, the second-level sub-stratification includes:

[0037] When heterogeneous application models exist, all heterogeneous application models are retrieved from the sea. Figure 3 The model is separated from the application model and denoted as the association layer model, which is independent of the application model. The association layer model is a model that is associated with the element called by the user.

[0038] Web Zhonghai Figure 3 Models outside the calling application model and the associated layer model within the dimensional model are denoted as unassociated models. Based on the existence of chart tile models corresponding to all element labels in the unassociated models, the unassociated models are processed into layers. After the unassociated models are processed into layers, each layer corresponds to a chart tile model with one element label.

[0039] The beneficial effects of this invention are as follows: This application first obtains a three-dimensional model corresponding to the electronic nautical chart sheet, and denotes it as a sea map. Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The 3D model undergoes feature extraction processing, and based on the results, a corresponding sub-model for each element of the nautical chart is obtained. Then, all sub-models are analyzed, and based on the analysis results, a connection model for each sub-model is obtained. The advantage of this approach is that by analyzing the nautical chart model, a connection model for each sub-model can be obtained. Figure 3 The 3D model is used to extract features to obtain the nautical chart sub-model, which can identify the location of each element in the electronic nautical chart sheet. Figure 3 The models in the dimensional model are effectively distinguished, and by obtaining the connecting model of the chart sub-model, the model that is simultaneously in multiple chart sub-models can be obtained. This allows the model corresponding to the required data to be obtained in a targeted manner based on the user's needs after obtaining the elements required by the user, thereby improving the user's speed of analyzing chart data when browsing chart data on the web.

[0040] This application also analyzes the connection model based on the chart sub-model and obtains the connection preference of each connection model based on the analysis results; finally, the elements called when using electronic chart sheets are recorded as real-time analysis elements, and the chart sub-models corresponding to the real-time analysis elements are recorded as hierarchical models; based on the hierarchical models and the connection preferences of the connection models corresponding to the hierarchical models, the connection preference of each connection model is obtained. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 Displaying the dimensional model on the web has the advantage that, by obtaining the connection preferences of the connection model, a more suitable sub-model of the chart can be obtained, thereby enabling subsequent analysis of the chart on the web. Figure 3 When layering a dimensional model, the hierarchy of connecting models can be set more flexibly to ensure the smooth operation of the layered model. Figure 3 The 3D model better meets users' needs and improves the speed at which users can analyze nautical chart data. Attached Figure Description

[0041] Figure 1 This is a flowchart of the steps of the method of the present invention;

[0042] Figure 2 The present invention relates to the sea in the web. Figure 3 Flowchart of the steps for hierarchical processing of a 3D model;

[0043] Figure 3 This is a schematic diagram of the electronic device of the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Example 1, please refer to Figure 1 As shown, this application provides a web-based vectorized layered display method based on electronic nautical chart sheets, including the following steps:

[0046] Step S1: Obtain the 3D model corresponding to the electronic nautical chart sheet and denot it as the sea. Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The dimensional model is subjected to feature extraction processing, and the corresponding nautical chart sub-model for each element is obtained based on the result of feature extraction processing. The elements include geographic features, navigation features and hydrological features.

[0047] In this embodiment, only the geographical elements, navigation elements, and hydrological elements in the electronic nautical chart are analyzed. In the actual implementation process, the elements contained in the elements can be added, deleted, or modified according to the element composition in the electronic nautical chart during the actual analysis, that is, the geographical elements, navigation elements, and hydrological elements can be added, deleted, or modified.

[0048] Step S1 includes: Step S101, establishing a spatial coordinate system with all coordinate axes in meters (m) and denoted as θ_h Figure 3 A 3D coordinate system was established; data corresponding to the electronic nautical chart sheets were read and elevation information was extracted. Interpolation and gridding were used to convert the 2D data of the electronic nautical chart sheets into 3D terrain data, and 3D modeling techniques were used to model the terrain at sea. Figure 3 Obtain the 3D model corresponding to the electronic nautical chart sheet in a 3D coordinate system, denoted as nautical map sheet. Figure 3 3D model;

[0049] In the specific implementation process, elevation information is the vertical distance from a point along the plumb line to a certain reference surface. It is usually used to describe the altitude or relative height of the ground surface or object. Elevation information can be obtained from the data in the electronic nautical chart to provide data support for the acquisition of three-dimensional terrain data.

[0050] Step S102: Based on the geographic elements, navigation elements and hydrological elements contained in the electronic nautical chart, establish a geographic database, a navigation database and a hydrological database respectively, and store the data corresponding to the geographic elements, navigation elements and hydrological elements in the electronic nautical chart.

[0051] Step S103 involves analyzing the sea data based on data from the geographic database, navigation database, and hydrological database. Figure 3 The dimensional model is subjected to feature extraction processing, and the corresponding nautical chart sub-models for geographic features, navigation features and hydrological features are obtained based on the processing results;

[0052] Step S104, the feature extraction process includes: Step S1041, for any element among geographic features, navigation features, and hydrological features: the data corresponding to the element in the electronic nautical chart sheet is recorded as element data, and the labeled objects corresponding to the element data in the electronic nautical chart sheet are recorded as element labels; in the sea Figure 3 Mark the positions of all element markers in the 3D coordinate system;

[0053] In practical implementation, the element labels in geographic elements can include the coastlines of the mainland and islands and the boundaries of dry beaches, forming the sea-land boundary baseline, water depth point numerical labels, isobaths, seabed types, significant landforms, port facilities, and other positioning references; the element labels in navigation elements can include navigation facilities such as buoys, lighthouses, and guide beacons, dangerous objects such as shipwrecks, reefs, and fishing fences, and markings for channel boundaries, traffic separation systems, anchorage areas, and no-navigation zones; the element labels in hydrological elements can include real-time hydrological information such as tide tables, ocean current vectors, and magnetic deviations, latitude and longitude grids and asymptotic latitude scales, map names, numbers, scales, publishing institutions, datums, coordinate systems, and Notices to Navigation version numbers; the element labels corresponding to geographic, navigation, and hydrological elements can be set according to the elements existing in the actual electronic nautical chart sheet; by acquiring the element labels and obtaining the corresponding nautical chart tile models during subsequent analysis, the models corresponding to the objects contained in the elements can be acquired in greater detail, so that the obtained nautical chart sub-models can effectively reflect the three-dimensional model corresponding to each element.

[0054] Step S1042: Obtain the vector tiles corresponding to the electronic nautical chart sheet based on GeoServer. When generating vector tiles, obtain the vector tiles corresponding to each element marker generated by the electronic nautical chart sheet based on the position data of the element markers of all elements, and record them as the marker tiles of the element markers.

[0055] In the specific implementation process, GeoServer is a tool for converting electronic nautical chart sheets into vector tiles. GeoServer can be replaced with any tool that can be obtained to convert electronic nautical chart sheets into vector tiles during the actual analysis.

[0056] Step S1043: For any one of the geographic, navigational, and hydrological elements: acquire the data of the electronic nautical chart sheet contained in each labeled tile, and record it as the nautical chart tile data of the labeled tile; in the sea Figure 3The model corresponding to the nautical chart tile data is obtained from the dimensional model and denoted as the nautical chart tile model;

[0057] Step S1044: Place the nautical chart tile models corresponding to all the labeled tiles of the element in the same blank sea area. Figure 3 Within a 3D coordinate system, and at this time the sea Figure 3 A three-dimensional model in a 3D coordinate system is denoted as an element-based chart sub-model;

[0058] Step S1045: Obtain the chart sub-models corresponding to geographic elements, navigation elements, and hydrological elements respectively. In the specific implementation process, by obtaining the chart sub-model of each element in the electronic chart sheet, after obtaining the elements required by the user, the model corresponding to the required data can be obtained in a targeted manner based on the user's needs, thereby improving the user's analysis speed of chart data when browsing chart data on the web.

[0059] Step S2: Analyze all chart sub-models and obtain the connection model for each chart sub-model based on the analysis results; analyze the connection model based on the chart sub-models and obtain the connection preference for each connection model based on the analysis results;

[0060] Step S2 includes: Step S201, for any two elements corresponding to the chart sub-model α and chart sub-model β: place the chart sub-model α and chart sub-model β in the same blank sea... Figure 3 In a 3D coordinate system, the model in which the chart sub-model α and the chart sub-model β coincide is denoted as the connecting model;

[0061] Step S202, for chart sub-model α or chart sub-model β: denote the chart slice models corresponding to the chart sub-models as chart slice model HQ1 to chart slice model HQ, respectively. r Where r is the number of chart tile models corresponding to the chart sub-model; for any chart tile model HQ t When the nautical chart slice model HQ t When there is an overlapping area with the connection model, the nautical chart slice model HQ will be used. t The region that overlaps with the connecting model is denoted as the slice overlap model; the volume of the slice overlap model is denoted as v, and the number of element labels corresponding to the elements of the nautical chart sub-model contained in the slice overlap model is denoted as u, where t is a positive integer less than or equal to r and greater than or equal to 1.

[0062] Step S203, when the nautical chart slice model HQ t When there is no overlapping area with the connection model, the nautical chart slice model HQ is used. t This is denoted as an unrelated model; the value of r divided by the number of unrelated models in all nautical chart slice models is denoted as the unrelated proportion.

[0063] In the specific implementation process, since the chart slice model is part of the chart sub-model, the chart slice model may have overlapping areas with the connecting model, or it may not have overlapping areas with the connecting model. Therefore, in this embodiment, the correlation between the chart sub-model and the connecting model is integrated by taking into account the correlation between all chart slice models and the connecting model in the chart sub-model. That is, by obtaining the volume of the overlapping slice model, the number of element labels of the elements corresponding to the chart sub-models contained in the overlapping slice model, and the proportion of unrelated elements, and further obtaining the preference value, the correlation between the chart sub-model and the connecting model can be obtained; V, U, and irrelevant values. A higher correlation ratio indicates a larger overlap between the chart tile model and the connecting model in the chart sub-model, a greater number of element labels in the overlapping area, and a greater number of chart tile models not recorded as unrelated models. In other words, the correlation between the chart sub-model and the connecting model is stronger. Therefore, by comparing the preference values ​​of the two chart sub-models corresponding to the connecting model, a chart sub-model with a stronger correlation to the connecting model can be obtained, thus setting the connecting preference for the chart sub-model. By obtaining the connecting preference of the connecting model, a chart sub-model that is more suitable for the connecting model can be obtained, thereby enabling subsequent analysis of charts in the web. Figure 3 When layering a dimensional model, the hierarchy of connecting models can be set more flexibly to ensure the smooth operation of the layered model. Figure 3 The 3D model better meets users' needs and improves the speed at which users can analyze nautical chart data.

[0064] Step S204: Establish a Cartesian coordinate system and denote it as the preference comparison coordinate system. The X-axis and Y-axis of the preference comparison coordinate system are constant axes. In the preference scale coordinate system, establish three rays with the origin as the endpoint and denote them as γ1, γ2 and γ3 respectively. The acute angle formed by γ1 and γ2 at the origin is 60°, the acute angle formed by γ1 and γ3 at the origin is 60°, and γ2 and γ3 do not coincide.

[0065] Step S205: In γ1, obtain the point with a distance of V from the origin and record it as the volume point; in γ2, obtain the point with a distance of U from the origin and record it as the overlapping quantity point; in γ3, obtain the point with a distance of no correlation ratio from the origin and record it as the ratio point. Here, V is the sum of v corresponding to all chart tile models that are not recorded as no correlation models, and U is the sum of u corresponding to all chart tile models that are not recorded as no correlation models.

[0066] Step S206: Record the area of ​​the triangle formed by the volume point, the number of overlapping points, and the proportion point as the preference value; obtain the preference values ​​corresponding to the chart sub-model α and the chart sub-model β, and record the chart sub-model with the largest preference value as the connection preference of the connection model;

[0067] Step S207: Obtain the connection model between the sub-models of the chart corresponding to all elements and the connection preference of each connection model.

[0068] Step S3: Elements invoked when using electronic nautical chart sheets are designated as real-time analysis elements, and the corresponding chart sub-models are designated as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the nautical chart sub-models are analyzed. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 The dimensional model is displayed on the web.

[0069] Step S3 includes: Step S301, placing the sea Figure 3 Import the dimensional model into the web for browsing; when using electronic nautical chart sheets, the elements called in the electronic nautical chart sheets will be recorded as real-time analysis elements, and the nautical chart sub-models corresponding to the real-time analysis elements will be recorded as hierarchical models;

[0070] Step S302: Obtain all connection models corresponding to the hierarchical model and record them as models to be added; for any model to be added: when the connection preference of the model to be added is a hierarchical model, record the model to be added as a same-layer application model; when the connection preference of the model to be added is not a hierarchical model, record the model to be added as a different-layer application model.

[0071] For step S303, please refer to [link / reference]. Figure 2 As shown, for the sea in the web Figure 3 The dimensional model is processed in layers.

[0072] Step S304, the hierarchical processing includes a primary hierarchical level and a secondary hierarchical level; Step S3041, the primary hierarchical level includes:

[0073] When a peer-to-peer application model exists, the web will be in the middle. Figure 3 Same-layer application models within a dimensional model and hierarchical models from the sea Figure 3 The dimensional model is stripped and recorded as the calling application model; when no application model exists in the same layer, the web layer is... Figure 3 Hierarchical models within a dimensional model from the sea Figure 3 The model is stripped from the dimensional model, where the application model is the model corresponding to the element called by the user.

[0074] Step S3042, the second-level sub-layer includes: when heterogeneous application models exist, retrieving all heterogeneous application models from the sea... Figure 3 The model is separated from the application model and denoted as the association layer model, which is independent of the application model. The association layer model is a model that is associated with the element called by the user.

[0075] Web Zhonghai Figure 3Models outside the calling application model and the associated layer model within the dimensional model are denoted as unassociated models. Based on the existence of chart tile models corresponding to all element labels in the unassociated models, the unassociated models are processed into layers. After the unassociated models are processed into layers, each layer corresponds to a chart tile model with one element label.

[0076] Example 2, please refer to Figure 3 As shown, Figure 3 A schematic diagram of an electronic device is provided, which may include a processor, a communication interface, a memory, and a communication bus. The processor, communication interface, and memory communicate with each other via the communication bus. The memory stores computer-readable instructions, and the processor can call these instructions. When the processor executes a computer-readable instruction, it performs steps similar to those in a web-based vectorized layered display method based on electronic nautical chart sheets to achieve the following functions: First, it acquires the 3D model corresponding to the electronic nautical chart sheet and denotes it as a sea... Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The system performs feature extraction on the 3D model and obtains the corresponding chart sub-model for each element based on the feature extraction results. Then, it analyzes all chart sub-models and obtains the connection model for each sub-model based on the analysis results. The connection model is then analyzed based on the chart sub-models, and the connection preference for each connection model is obtained based on the analysis results. Finally, the elements called when using electronic chart sheets are recorded as real-time analysis elements, and the chart sub-models corresponding to these real-time analysis elements are recorded as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the system analyzes the chart sub-models for each element. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 The dimensional model is displayed on the web.

[0077] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0078] Example 3: This application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by the computer, the computer can execute a web vectorized layered display method based on electronic nautical chart sheets provided by the above methods. The method includes: firstly, obtaining a three-dimensional model corresponding to the electronic nautical chart sheet, and denoting it as a sea... Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The system performs feature extraction on the 3D model and obtains the corresponding chart sub-model for each element based on the feature extraction results. Then, it analyzes all chart sub-models and obtains the connection model for each sub-model based on the analysis results. The connection model is then analyzed based on the chart sub-models, and the connection preference for each connection model is obtained based on the analysis results. Finally, the elements called when using electronic chart sheets are recorded as real-time analysis elements, and the chart sub-models corresponding to these real-time analysis elements are recorded as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the system analyzes the chart sub-models for each element. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 The dimensional model is displayed on the web.

[0079] Example 4: This application also provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it performs the steps of the above-described web vectorization layered display method based on electronic nautical chart sheets to achieve the following functions: First, it obtains the three-dimensional model corresponding to the electronic nautical chart sheet and denotes it as a sea... Figure 3 3D model; based on elements contained in electronic nautical chart sheets for understanding the sea Figure 3 The system performs feature extraction on the 3D model and obtains the corresponding chart sub-model for each element based on the feature extraction results. Then, it analyzes all chart sub-models and obtains the connection model for each sub-model based on the analysis results. The connection model is then analyzed based on the chart sub-models, and the connection preference for each connection model is obtained based on the analysis results. Finally, the elements called when using electronic chart sheets are recorded as real-time analysis elements, and the chart sub-models corresponding to these real-time analysis elements are recorded as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the system analyzes the chart sub-models for each element. Figure 3 The 3D model is processed into layers, and the resulting sea Figure 3 The dimensional model is displayed on the web.

[0080] Based on the above description of the embodiments, the embodiments of the present invention can be provided as methods, systems, or computer program products. Based on this understanding, the above technical solutions, in essence or in terms of their contribution to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or certain parts of the embodiments.

[0081] In the embodiments provided in this application, it should be understood that the disclosed system or method can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of modules or units is only a logical functional division, and there may be other division methods in actual implementation. Furthermore, multiple modules or units may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces. The indirect coupling or communication connection between systems, modules, and units may be electrical, mechanical, or other forms.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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. Such 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 this application.

Claims

1. A web-based vectorized layered display method based on electronic nautical chart sheets, characterized in that, Includes the following steps: Obtain the 3D model corresponding to the electronic nautical chart sheet and denote it as the nautical chart 3D model; perform feature extraction processing on the nautical chart 3D model based on the elements contained in the electronic nautical chart sheet, and obtain the nautical chart sub-model corresponding to each element based on the result of feature extraction processing. The elements include geographic elements, navigation elements and hydrological elements. Analyze all chart sub-models and obtain the connection model for each chart sub-model based on the analysis results; analyze the connection model based on the chart sub-models and obtain the connection preference for each connection model based on the analysis results; Elements invoked when using electronic nautical chart sheets are denoted as real-time analysis elements, and the corresponding chart sub-models are denoted as hierarchical models. Based on the hierarchical models and the connection preferences of the corresponding connection models, the 3D nautical chart model is hierarchically processed, and the hierarchically processed 3D nautical chart model is displayed on the web.

2. The web-based vectorized layered display method based on electronic nautical chart sheet as described in claim 1, characterized in that, The 3D model of the nautical chart is characterized by feature extraction based on the elements contained in the electronic nautical chart sheet, and the sub-model of the nautical chart corresponding to each element is obtained based on the result of the feature extraction process, including: A spatial coordinate system with all axes in meters is established and denoted as the nautical chart three-dimensional coordinate system. Data corresponding to the electronic nautical chart sheet is read and elevation information is extracted from the data. Interpolation and gridding are used to convert the two-dimensional data corresponding to the electronic nautical chart sheet into three-dimensional terrain data. Three-dimensional modeling technology is used to obtain the three-dimensional model corresponding to the electronic nautical chart sheet in the nautical chart three-dimensional coordinate system, denoted as the nautical chart three-dimensional model. Based on the geographic, navigational, and hydrological elements contained in the electronic nautical chart, a geographic database, a navigational database, and a hydrological database are established to store the data corresponding to the geographic, navigational, and hydrological elements in the electronic nautical chart. The 3D nautical chart model is characterized by feature extraction based on data from geographic databases, navigation databases, and hydrological databases, and the corresponding nautical chart sub-models are obtained based on the processing results.

3. The web-based vectorized layered display method based on electronic nautical chart sheet as described in claim 2, characterized in that, Feature extraction processing includes: For any element among geographic, navigational, and hydrological elements: the data corresponding to the element in the electronic chart sheet is recorded as element data, and the labeled objects corresponding to the element data in the electronic chart sheet are recorded as element labels; the positions of all element labels are marked in the three-dimensional coordinate system of the chart. Based on GeoServer, vector tiles corresponding to the electronic nautical chart sheet are obtained. When generating vector tiles, the vector tiles corresponding to each element marker generated from the electronic nautical chart sheet are obtained based on the position data of the element markers of all elements, and are recorded as the marker tiles of the element markers.

4. The web-based vectorized layered display method based on electronic nautical chart sheet as described in claim 3, characterized in that, Feature extraction processing also includes: For any one of the geographic, navigational, and hydrological elements: obtain the data of the electronic chart sheet contained in each labeled tile and record it as the chart tile data of the labeled tile; obtain the model corresponding to the chart tile data in the 3D chart model and record it as the chart tile model; Place the chart tile models corresponding to all the labeled tiles of the element in the same blank chart 3D coordinate system, and denote the 3D model in the chart 3D coordinate system at this time as the chart sub-model of the element. Obtain the corresponding nautical chart sub-models for geographic features, navigation features, and hydrological features respectively.

5. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 4, characterized in that, Analyze all chart sub-models and obtain the connection model for each chart sub-model based on the analysis results; The connectivity models are analyzed based on the nautical chart sub-model, and the connectivity preferences of each connectivity model are obtained based on the analysis results, including: For any two elements, the corresponding chart sub-models α and β are placed in the same blank chart 3D coordinate system, and the model where the chart sub-models α and β coincide is called the connecting model. For chart submodel α or chart submodel β: the corresponding chart slice models are denoted as chart slice model HQ1 to chart slice model HQ, respectively. r Where r is the number of chart tile models corresponding to the chart sub-model; for any chart tile model HQ t When the nautical chart slice model HQ t When there is an overlapping area with the connection model, the nautical chart slice model HQ will be used. t The region that overlaps with the connecting model is denoted as the slice overlap model; the volume of the slice overlap model is denoted as v, and the number of element labels corresponding to the elements of the nautical chart sub-model contained in the slice overlap model is denoted as u, where t is a positive integer less than or equal to r and greater than or equal to 1.

6. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 5, characterized in that, The analysis of the connectivity models based on the nautical chart sub-model, and the acquisition of the connectivity preferences for each connectivity model based on the analysis results, also includes: When the nautical chart slice model HQ t When there is no overlapping area with the connection model, the nautical chart slice model HQ is used. t This is denoted as an unrelated model; the value of r divided by the number of unrelated models in all nautical chart slice models is denoted as the unrelated proportion. Establish a Cartesian coordinate system, denoted as the preference comparison coordinate system, where the X-axis and Y-axis are constant axes. In the preference scale coordinate system, establish three rays with the origin as the endpoint, denoted as γ1, γ2, and γ3 respectively. The acute angle formed by γ1 and γ2 at the origin is 60°, the acute angle formed by γ1 and γ3 at the origin is 60°, and γ2 and γ3 do not coincide.

7. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 6, characterized in that, The analysis of the connectivity models based on the nautical chart sub-model, and the acquisition of the connectivity preferences for each connectivity model based on the analysis results, also includes: In γ1, a point with a distance of V from the origin is obtained and denoted as a volume point. In γ2, a point with a distance of U from the origin is obtained and denoted as a coincidence quantity point. In γ3, a point with a distance of no correlation scale from the origin is obtained and denoted as a scale point. Here, V is the sum of v corresponding to all chart tile models that are not denoted as no correlation models, and U is the sum of u corresponding to all chart tile models that are not denoted as no correlation models. The area of ​​the triangle formed by the volume point, the number of overlapping points, and the proportion point is recorded as the preference value; the preference values ​​corresponding to the chart sub-model α and the chart sub-model β are obtained, and the chart sub-model with the largest preference value is recorded as the connection preference of the connection model; Obtain the connection models between the chart sub-models corresponding to all elements, as well as the connection preferences of each connection model.

8. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 7, characterized in that, Based on the hierarchical model and the connection preferences of the corresponding connection model, the 3D nautical chart model is hierarchically processed, and the hierarchically processed 3D nautical chart model is displayed on the web, including: Import the 3D model of the nautical chart into the web for browsing; when using the electronic nautical chart sheet, the elements called in the electronic nautical chart sheet will be recorded as real-time analysis elements, and the nautical chart sub-models corresponding to the real-time analysis elements will be recorded as hierarchical models; Obtain all connecting models corresponding to the hierarchical model and record them as models to be added; for any model to be added: when the connecting preference of the model to be added is a hierarchical model, record the model to be added as a same-layer application model; when the connecting preference of the model to be added is not a hierarchical model, record the model to be added as a different-layer application model. Layering is performed on the 3D model of nautical charts in the web.

9. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 8, characterized in that, Layered processing includes a primary layer and secondary layers. The primary layer includes: When a same-layer application model exists, the same-layer application model and the layerable model within the 3D model of the nautical chart in the web are separated from the 3D model of the nautical chart and recorded as the calling application model; when no same-layer application model exists, the layerable model within the 3D model of the nautical chart in the web is separated from the 3D model of the nautical chart. The calling application model is the model corresponding to the element called by the user.

10. A web-based vectorized layered display method based on electronic nautical chart sheets according to claim 9, characterized in that, Secondary sub-strata include: When heterogeneous application models exist, all heterogeneous application models are separated from the 3D nautical chart model and recorded as related layer models that are independent of the calling application models. The related layer model is a model that is associated with the element called by the user. Models outside the calling application model and the associated layer model in the web 3D nautical chart model are denoted as unassociated models. Based on the existence of nautical tile models corresponding to all element labels in the unassociated models, the unassociated models are layered. After the unassociated models are layered, each layer corresponds to a nautical tile model with one element label.

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