A cesium-based tower model layered rendering and interaction method and system

Abstract

This application discloses a Cesium-based method and system for layered rendering and interaction of tower models, belonging to the field of industrial infrastructure asset visualization management. The method includes: splitting the tower model into multiple layered models, adding unique identifiers to each layered model, and generating texture files of different levels of detail; constructing a tower attribute database; constructing a standard object model library to store layered templates for towers in various industries; when loading a tower model, after selecting a target layered model, rendering the target layered model of different levels of detail using texture files based on line-of-sight, frame rate, and network bandwidth; when picking a tower model, selecting the target tower model using a unique identifier, and simultaneously retrieving the attribute data of each target layered model from the tower attribute database and displaying it in the interactive area to achieve information interaction with the user. This method can improve rendering efficiency and operational interaction experience.

Description

Technical Field

[0001] This application belongs to the field of visual management of industrial infrastructure assets, and specifically relates to a method and system for layered rendering and interaction of iron tower models based on Cesium. Background Technology

[0002] As core infrastructure in fields such as communications and power, towers are characterized by their wide distribution, large scale, and significant differences in industry attributes. Specifically, telecommunications towers often house antennas, remote radio units (RRUs), baseband processing units (BBUs), feeders, and other equipment from multiple telecommunications operators, requiring collaborative management and precise operation and maintenance of multiple devices. Power industry towers (such as 500kV transmission towers and substation frame towers) prioritize load-bearing performance and insulation design, featuring complex structures that support high-voltage transmission lines, with a focus on safety monitoring and parameter control. While the structural forms, auxiliary equipment, core parameters, and operation and maintenance requirements of towers vary significantly across industries, they all share a common need for large-scale visualization and refined management.

[0003] The Cesium engine, with its powerful geospatial data integration capabilities, cross-platform compatibility, and high-resolution visualization effects, has become the mainstream technology choice for 3D visualization of large-scale industrial infrastructure. However, when dealing with large-scale tower models (typically, a single administrative province may have tens of thousands of towers, with each tower containing multiple structural components and attribute data), existing technologies have the following key shortcomings: Insufficient industry-specific adaptation: Traditional rendering methods lack specific adaptation designs for the characteristics of communication tower equipment and the insulation structure requirements of power towers. The rendering and interaction logic of core scenarios (such as multi-operator equipment management of communication towers and insulator status monitoring of power towers) is imperfect, resulting in the inability to meet core requirements. The rendering efficiency bottleneck is prominent: the geometric data (such as multiple antennas of communication towers and complex crossarms of power towers), texture data and attribute data of large-scale tower models are huge. If the overall loading mode is adopted, it will consume a lot of memory and network bandwidth, resulting in page loading delay, frame rate drop, or even lag and crash, which cannot meet the real-time visualization needs of tens of thousands of tower scenes. Insufficient granularity in layered interaction: Existing technologies make it difficult to achieve precise layered picking and independent control of towers. Users cannot filter target components according to industry characteristics (such as RRU equipment for communication towers and insulators for power towers), nor can they quickly retrieve differentiated attribute data (such as equipment operators for communication towers and rated voltage for power towers), resulting in low operation and maintenance efficiency. The data linkage mechanism is inadequate: the real-time status data of the towers (such as the equipment operating temperature of communication towers and the conductor tension of power towers) and the 3D model lack industry-adapted linkage logic, making it impossible to trigger visual early warnings according to industry standards. Furthermore, the association between attribute data and the model is loose, making it difficult to support intelligent management decisions. Weak multi-device adaptability: Existing methods cannot dynamically adjust the model loading strategy in different terminals such as mobile inspection equipment and PC management platforms, and in different network environments such as outdoor weak network and indoor high-speed network, resulting in slow loading on mobile devices and wasted performance of high-performance devices.

[0004] These problems severely restrict the practicality and efficiency of large-scale tower model visualization systems, making it difficult to be compatible with the differentiated application scenarios of towers in different industries, thus limiting the promotion and implementation of the technology. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a Cesium-based method and system for layered rendering and interaction of tower models. By utilizing model layered deconstruction, unique identifier association, multi-dimensional dynamic rendering, precise picking interaction, and industry-customized data linkage technology, it can achieve efficient rendering and precise interaction of tower models across multiple industries.

[0006] The following is the technical content of this disclosure: A layered rendering and interaction method for the Eiffel Tower model based on Cesium, comprising: After splitting the Eiffel Tower model into multiple layers, a unique identifier is added to each layer, and texture files of different levels of detail are generated. A tower attribute database is constructed to store attribute data of models at each level. The tower attribute database establishes the association between tower attribute data and models at each level through unique identifiers. A standard object model library is constructed to store hierarchical templates of towers in various industries. When loading the tower model, after selecting the target layered model from the standard object model library, the target layered model with different levels of detail is rendered using the texture file based on the line of sight, frame rate and network bandwidth. When picking a tower model, the target tower model is selected by a unique identifier. At the same time, the attribute data of each target layer model is obtained from the tower attribute database and displayed in the interactive area to realize information interaction with the user.

[0007] Furthermore, The multiple hierarchical models include: Basic layer, main structure layer, industry-specific layer, and identification layer; The unique identifier is: Tower ID - Industry Code - Hierarchical ID.

[0008] Furthermore, The tower attributes in the tower attribute database include: unique identifier, industry type, geometric parameters, material information, core fields, and extended fields; When the tower is a communication tower, the core fields include: operator, frequency band, and transmission power; When the tower is a power tower, the extended fields include: rated voltage and conductor type.

[0009] Furthermore, When loading the tower model, the layered models are loaded according to priority order. The priorities, from highest to lowest, are: main structure layer, industry-specific layer, basic layer, and identification layer.

[0010] Furthermore, When rendering hierarchical target models of varying detail based on view distance: Obtain the camera coordinates of Cesium and calculate the distance d between it and the center point of the tower; When the distance d is greater than the first distance threshold, the main structure layer model is loaded with the first level of refinement. When the second distance threshold ≤ distance d ≤ the first distance threshold, the main structure layer is loaded with the second level of fineness, the basic layer and the corresponding industry-specific layer are loaded with the first level of fineness; When the distance d is less than the second distance threshold, all levels of the model are loaded with the third level of refinement. Among them, the first level of refinement is less than the second level of refinement, which is less than the third level of refinement.

[0011] Furthermore, When picking up the tower model, the Cesium ray detection mechanism is used, and the tower model is picked up by filtering through a unique identifier.

[0012] Furthermore, When rendering hierarchical target models of varying detail based on frame rate: If the rendering frame rate is lower than the first frame rate threshold, reduce the model rendering detail and hide the identifier layer and some industry-specific layer models. If the rendering frame rate is higher than the second frame rate threshold, restore the model rendering detail and display the full-level model.

[0013] Furthermore, The feature is that the step of obtaining attribute data of each target hierarchical model from the tower attribute database and displaying it in the interactive area to achieve information interaction with the user includes: A quadtree spatial index is constructed for the tower model using planar coordinates. Only tower data from the specified industry that falls within the current viewport range is loaded and displayed in the interactive area.

[0014] A layered rendering and interactive system for the Eiffel Tower model based on Cesium, including: The model splitting module is used to split the Eiffel Tower model into multiple layers, add a unique identifier to each layer, and generate texture files with different levels of detail. The database construction module is used to build a tower attribute database to store attribute data of models at each level. The tower attribute database establishes the association between tower attribute data and models at each level through unique identifiers. The module also builds a standard object model library to store hierarchical templates for towers in various industries. The model loading module is used to select a target layered model from the standard object model library when loading the tower model, and then render target layered models of different levels of detail using the texture file based on the line of sight, frame rate and network bandwidth. The model interaction module is used to select the target tower model by a unique identifier when picking a tower model. At the same time, it retrieves the attribute data of each target layer model from the tower attribute database and displays it in the interaction area to realize information interaction with the user.

[0015] Furthermore, The tower attributes in the tower attribute database include: unique identifier, industry type, geometric parameters, material information, core fields, and extended fields; When the tower is a communication tower, the core fields include: operator, frequency band, and transmission power; When the tower is a power tower, the extended fields include: rated voltage and conductor type.

[0016] Compared with the prior art, this application has the following advantages: By deconstructing the integrated, complex model into functionally and structurally independent units, the resource redundancy bottleneck caused by overall loading can be resolved. The unique identifier establishes an unambiguous mapping link between model entities and business data, providing a stable and accurate indexing foundation for digital-model linkage. The standard object model library unifies the structural layering and template specifications of towers in different industries, eliminating the fragmentation and lack of specificity in industry adaptation. Multi-dimensional dynamic rendering adaptively adjusts rendering resources according to scene and network conditions, balancing visualization effects and system operating efficiency. The precise picking and attribute linkage driven by the unique identifier enables refined control of tower units and rapid information retrieval. Therefore, it can comprehensively solve the technical problems of insufficient industry adaptation specificity, prominent rendering efficiency bottlenecks, insufficient refinement of layered interaction, imperfect data linkage mechanism, and weak multi-device adaptation capabilities.

[0017] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the method of this disclosure is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The following is the method disclosed in this publication: A layered rendering and interaction method for the Eiffel Tower model based on Cesium, such as Figure 1 As shown, it includes: Step 1: First, break down the tower model into multiple layers: base layer, main structure layer, industry-specific layer, and identification layer. Add a unique identifier of tower ID-industry code-layer ID to each layer and generate texture files of different levels of detail. Furthermore, step 1 specifically includes: S11: Constructs a four-tiered architecture: "Basic Layer - Main Structure Layer - Industry-Specific Layer - Identification Layer," balancing universality and industry specificity, with a core focus on enhanced communication tower adaptability design: Basic Layer: Universal across all industries, including tower base, anchor bolts, foundation concrete structure, and other load-bearing components; Main Structure Layer: Universal across all industries, including tower legs, tower segments, crossarms, diagonal braces, and other core load-bearing structures; Industry-Specific Layer: Corely adapts to communication towers while also being compatible with other industries. The communication tower-specific layer includes antenna layer, RRU / BBU layer, feeder layer, and lightning protection facility layer; the power tower-specific layer includes insulator layer, transmission line layer, and equipotential ring layer; other industry-specific towers can be expanded to add additional exclusive layers (such as the nacelle layer for wind turbine towers); Identification Layer: Universal across all industries, including tower number nameplates, industry attribute identifiers (such as operator identifiers for communication towers, voltage level identifiers for power towers), safety warning signs, etc. S12: Convert the model data of each level into a format supported by Cesium, add a three-level unique identifier for each level consisting of tower ID, industry code, and level ID; compress the model texture; highlight the model identification and operator identification for the equipment texture of the communication tower, and retain the insulation material details for the insulator texture of the power tower. The overall preset has three levels of fineness: high, medium, and low. Step 2: Construct a tower attribute database to store attribute data for each level of the model. The attribute data includes unique identifiers, industry type, geometric parameters, material information, core fields, and extended fields. The core fields for communication towers are operator, frequency band, and transmission power, while the extended fields for power towers are rated voltage and conductor type. This database establishes a connection between each level of the model through unique identifiers. At the same time, a standard object model library is constructed to store the hierarchical templates of towers in various industries. Furthermore, step 2 specifically includes: S21: Establish a core + extended attribute field library: The core field library adapts to the needs of communication towers and includes equipment operator, frequency band, transmission power, installation date, etc.; the extended field library is compatible with other industries, and power towers add fields such as rated voltage, conductor type, insulation class, etc., and realize one-to-one association between attribute data and model through three-level ID; S22: Standard Object Model Library Construction: Build a pre-set standard object model library, which stores basic templates for each level of communication towers, and also includes layered templates for other industry towers such as power towers. Each template has a pre-set hierarchical structure framework and default attribute fields, supporting flexible expansion and reuse of industry templates.

[0022] Step 3: When loading the tower model, select the target layered model from the standard object model library according to the priority of the main structure layer, industry-specific layer, basic layer, and identification layer. Based on the line-of-sight, frame rate, and network bandwidth, render the target layered model with different levels of detail using texture files. When rendering based on line-of-sight, obtain the position of the Cesium camera and calculate the distance d between it and the center point of the tower. If the distance d is greater than the first distance threshold, load the main structure layer model with the first level of detail. If the second distance threshold ≤ d ≤ the first distance threshold, load the main structure layer with the second level of detail, load the basic layer and the corresponding industry-specific layer with the first level of detail. If d is less than the second distance threshold, load all layers with the third level of detail, and the first level of detail < the second level of detail < the third level of detail. When rendering based on frame rate, if the rendering frame rate is lower than the first frame rate threshold, reduce the model detail and hide the identification layer and some industry-specific layers. If it is higher than the second frame rate threshold, restore the detail and display the full layered model. Furthermore, step three specifically includes: S31. Configure the loading priority of the hierarchy. The priority from high to low is the main structure layer, industry-specific layer, basic layer, and identity layer. User-defined adjustments are supported. S32. Employs dynamic loading based on line-of-sight adaptation. By monitoring camera positions using Cesium, the distance between the camera and the tower model is calculated in real-time: Distance > L0: Only the low-resolution model of the main structure layer is loaded, hiding other layers; L1 < Distance ≤ L0: The main structure layer (medium resolution) and the foundation layer (low resolution) are loaded, with the core-specific layers of the communication tower (antenna layer, RRU layer, low resolution) loaded by default. Other industry towers are loaded according to their corresponding core layers; Distance < L1: All layers of high-resolution models are loaded to ensure detailed visualization (e.g., equipment interfaces of communication towers, insulator skirts of power towers); where L0 and L1 are distance thresholds, with L0 > L1. S33. Construct a quadtree spatial index for the tower model, load only the tower level data that intersects with the current viewport range, and retain only the simplified bounding box for models outside the viewport; Industry-filtered loading: only load tower models of the user-specified industry, and block data from other industries; S34. Monitor network bandwidth. In weak network environments, prioritize loading low-resolution models and core layers (main structure layer, communication tower antenna layer, etc.). In high-speed network environments, automatically load high-resolution models and all layers.

[0023] S35. Adaptive Rendering Optimization: Real-time monitoring of rendering frame rate. When the frame rate is lower than the specified threshold F0, the current loaded model's detail is automatically reduced from high detail to medium detail, and the identifier layer and non-core industry-specific layers are hidden. When the frame rate is higher than the specified threshold F1, high detail rendering and full-level display are restored. Where F0 < F1. Step 4: When picking up the tower model, the Cesium ray detection mechanism is used to achieve accurate picking through filtering with unique identifiers. At the same time, a quadtree spatial index is built for the tower model, and only tower data within the current viewport and the specified industry are loaded. The attribute data of each target hierarchical model is obtained from the tower attribute database and displayed in the interactive area to realize information interaction with the user.

[0024] Furthermore, step four specifically includes: S41. Based on the Cesium ray detection mechanism, the system uses "three-level ID" filtering to accurately pick up the user's click position, obtain the corresponding three-level ID, industry and related attribute data, and highlight them according to industry characteristics; S42. Use interactive panels adapted to core scenarios to control the visibility of different levels, including independent visibility of a single level and batch visibility of similar levels in the same industry. S43. Perform a joint filter based on industry type and attribute conditions, highlight the filter results in real time, and retrieve and display the target level attribute fields; S44. It adopts a dual caching mechanism of local storage + cloud synchronization to save users' operations such as hierarchical display, filtering conditions, and highlight status in real time, and automatically restores them after switching viewports, refreshing the page, or logging in across terminals.

[0025] Furthermore, it also includes: S51. Connects to various industry tower operation and maintenance management systems via the Web Socket protocol, receives real-time status data according to industry standards, and enables customized visual linkage: S52. Preset warning thresholds for various industries. When the status data exceeds the limit, automatically switch the corresponding level to warning color and push industry-specific warning information to the interactive panel.

[0026] Example 1: like Figure 1 As shown, this invention provides a method for layered rendering and interaction of large-scale Eiffel Tower models based on Cesium, including the following specific steps: S1: Perform standardized layered preprocessing on the tower model, consisting of "foundation layer - main structure layer - industry-specific layer - identification layer"; 1) Standardization and layering preprocessing of the tower model includes: using Blender software to perform layered decomposition of the communication tower (each tower carries 3 sets of operator antennas) and a certain 500kV power transmission tower: Communication tower: The structure consists of: a foundation layer (tower base concrete structure, anchor bolts), a main structure layer (4 tower legs, 10 tower body segments, 6 crossarms), an industry-specific layer (antenna layer, RRU / BBU layer, feeder layer, lightning protection facility layer), and a signage layer (tower number plate, operator identification plate). Power tower: The structure consists of: a foundation layer (tower base, anchor bolts), a main structure layer (6 tower legs, 15 tower body segments, 8 crossarms), an industry-specific layer (insulator layer, transmission line layer, equipotential ring layer, grounding device layer), and a marking layer (voltage level markings, safety warning signs). 2) Use the glTFTransform tool to convert each level model to glTF2.0 format and add a three-level unique identifier (tower ID-industry code-level ID) (e.g., the antenna layer ID of a communication tower is “T2024001-TX-TX003”, and the insulator layer ID of a power tower is “D2024005-DL-DL002”). 3) Use the BasisUniversal tool to compress the texture into ETC1S format, generating three levels of detail: high (2048×2048 pixels), medium (1024×1024 pixels), and low (512×512 pixels); S2: Generate hierarchical model data and associated attribute database with three-level unique identifiers (Tower ID - Industry Code - Hierarchical ID); 1) Construct a MySQL attribute database containing a tower hierarchy attribute table. Fields include a third-level ID, industry type, geometric parameters, material information, core fields (communication towers include operator, frequency band, and transmission power), and extended fields (power towers include rated voltage and conductor type). Establish a connection with the glTF model through the third-level ID. 2) Build a standard object model library, with the core storage being "communication tower templates" and also including "power tower templates". Each template has a four-level hierarchical framework and default attribute fields for the corresponding industry.

[0027] S3: Dynamic loading of layered models is achieved based on view distance, spatial index, and industry filtering, and adaptive rendering adjustment is performed in combination with frame rate and network bandwidth; 1) Configure the layer priority in the Cesium engine. The priorities from high to low are: main structure layer (1), industry-specific layer (2), basic layer (3), and identification layer (4). The antenna layer and RRU layer of the communication tower use priority 2 by default, and users can manually upgrade them to 1. Multi-dimensional dynamic loading logic: 2) Line-of-sight loading: The camera position is obtained through Cesium.Camera.prototype.positionCartographic, and the distance to the center point of the tower is calculated: When the distance is >800 meters, a low-resolution model of the main structure layer is loaded; when the distance is 50 meters ≤ distance ≤ 800 meters, a medium-resolution model of the main structure layer, a low-resolution model of the foundation layer, and a low-resolution model of the corresponding industry core-specific layer (communication tower antenna layer, RRU layer) are loaded; when the distance is <50 meters, a high-resolution model of all layers is loaded. 3) Spatial index scheduling: A 4-level quadtree index is used to divide the geographical area (each level node covers 10km×10km), and only the tower level data within the current viewport is loaded; 4) Adaptive optimization: Monitor the frame rate using Cesium.PerformanceWatchdog. When the frame rate is <25fps, switch the high-resolution model to medium-resolution and hide the identifier layer and non-core industry-specific layers. When the frame rate is ≥30fps, restore the initial settings. At the same time, monitor the network bandwidth. When the bandwidth is <1Mbps, prioritize loading the low-resolution model and the core layer.

[0028] S4: Achieves precise hierarchical picking through three-level ID filtering, providing layered interactive functions such as hierarchical visibility control, industry-attribute joint filtering, and exclusive information retrieval; hierarchical picking is implemented based on Cesium.RaycastQuery. 1) Pick-up method: When a user clicks on a scene, a ray is generated from the camera to the click point. The selected level is obtained by filtering through "three-level ID". Cesium.PostProcessStage is called to create a highlighted outline (red for communication towers, blue for power towers, with an outline width of 2 pixels). 2) Develop an interactive panel: including an industry filter area (providing checkboxes for industries such as communications and power), a hierarchy display control area (displayed according to a four-level hierarchical architecture, supporting single-level and batch display of the same type of hierarchy in the same industry), an attribute information display area (after selecting a hierarchy, the corresponding attribute data is retrieved from the MySQL database via an AJAX request and displayed in a table format), and an early warning information area (real-time display of exceeding the standard warning). 3) Persistence of interaction state: Local interaction state is stored using localStorage and synchronized to the cloud through the Node.js backend interface. The previous operation state is automatically restored after logging in across terminals or refreshing the page.

[0029] S5: Integrates with tower maintenance systems across various industries, receives real-time status data and triggers industry-customized visual alerts, maintaining data and model consistency through incremental update mechanisms. 1) Connect to the communication tower operation and maintenance system and the power industry transmission tower monitoring system via the WebSocket protocol, with the data push frequency set to 5 seconds / time, to receive real-time data such as the equipment operating temperature of the communication tower and the conductor tension of the power tower; 2) Configure industry early warning thresholds: Communication tower equipment temperature > 85℃, power tower conductor tension > 110% of design value. When the data exceeds the standard, call Cesium.MaterialProperty to create the corresponding industry early warning material (yellow flashing for communication towers, red flashing for power towers), and push an early warning prompt containing the level ID, the parameter exceeding the standard, and the handling suggestions in the early warning information area. 3) Incremental update: When the operator field of a communication tower or the insulator model of a power tower is changed in the attribute database, the changed data is pushed to the front end through the backend interface, and only the attribute information display of the corresponding level is updated without reloading the model.

[0030] Example 2 differs from Example 1 in that: The specific method for standardized stratified preprocessing is as follows: Establish a logical decomposition rule of "Basic Layer - Main Structure Layer - Industry-Specific Layer - Identification Layer". Communication Tower Decomposition: The main structure layer includes all standard segments, tower legs, crossarms, and common connectors; the industry-specific layer is further defined as the antenna layer, RRU / BBU equipment layer, feeder cabling layer, and lightning protection facility layer. The antenna layer can be defined as a sub-unit for each device (e.g., "the first antenna on the left platform"). Power Tower Decomposition: The main structure layer is the same as above; the industry-specific layer consists of the insulator layer (divided by string), transmission conductor layer (divided by phase), equipotential bonding ring / shielding ring layer, and grounding down conductor layer. Its significance lies in systematically decomposing the originally complex and singular tower BIM model into a collection of parts with independent business meaning, providing a structured data foundation for subsequent on-demand loading and independent control. Each split-level unit (such as an antenna or a string of insulators) is assigned a three-level unique identifier (tower global ID - industry code - level unit ID). For example, "T20240001_TX_ANT_001" represents tower number T20240001 (T), communication industry (TX), antenna layer (ANT), and unit number 001. Its significance lies in establishing a precise and unambiguous mapping relationship from 3D spatial objects to the backend business database. This identifier will serve as the core index key for all subsequent loading, picking, attribute querying, and data linkage, acting as a bridge to achieve "data-model integration." Every record in the attribute database must contain this three-level ID and be associated with the model file name or metadata, thereby enabling bidirectional queries within the system: "clicking on the model to see attributes" and "locating the model based on attributes."

[0031] The multi-level texture and lightweight model processing methods are as follows: the industry-standard glTF 2.0 format is used as the final output format of the layered model; BasisUniversal texture compression technology is used to generate three texture sets for the same model: high (2048x2048), medium (1024x1024), and low (512x512); the geometric model itself is also simplified according to the LOD principle. For example, the number of triangle faces in the low-level model can be reduced by more than 50%.

[0032] The specific methods of the layered model dynamic loading strategy include: Dynamic layer loading based on line-of-sight. The system calculates the spatial distance D between the Cesium camera and the center point of each tower in real time. Macro mode (D>800 meters): Only the low-resolution texture model of the main structural layer of the tower is loaded; all other layers are not loaded. The tower is displayed as a simplified outline on the map. Meso mode (50 meters ≤ D ≤ 800 meters): The medium-resolution model of the main structural layer and the low-resolution model of the foundation layer are loaded. Simultaneously, based on the tower's "industry code," the low-resolution models of its core "industry-specific layers" (such as the antenna layer and RRU layer of a communication tower, and the insulator layer of a power tower) are selectively loaded; the identification layer is still not loaded. Micro mode (D<50 meters or the user performs a "select / drill down" operation): All four layers of high-resolution models are fully loaded, ensuring that the user can view all information, including signs and bolt details. Its significance lies in transforming the rendering consumption of tens of thousands of iron towers across the country from an unbearable state of "full-scale high-resolution" to a state of "on-demand dynamic resolution" that is strongly correlated with the user's current focus. This algorithm ensures that GPU and memory resources are always focused on the most relevant data when users browse scenes at different scales, and is the core algorithm for achieving a smooth experience "from a single map of the whole country to the bolt-level resolution of a single tower".

[0033] Multi-level caching and preloading. Browser-side caching (LocalStorage / IndexedDB): Persistently stores downloaded, frequently used low-resolution model tiles and textures, enabling users to access the same area again with "zero" loading delays. Server-side pre-generated tiles (3DTiles): Using tools like CesiumLab, the processed layered model is divided into 3D Tiles sets based on geographic location and LOD. The Cesium engine can automatically request and schedule these tiles according to the view frustum. The significance lies in using a space-for-time strategy to distribute the massive network overhead of the initial load across subsequent browsing processes, and utilizing standard streaming technology to ensure the availability of ultra-large scene data.

[0034] The specific methods for implementing layered interaction and hybrid rendering are as follows: Cesium's native `scene.pick` method returns the outermost Primitive. In a hybrid rendering architecture, when picking occurs on a high-resolution BIM component rendered by Three.js, a custom event bridging module is used. The implementation works as follows: A transparent layer is overlaid on the Cesium Canvas for the Three.js renderer, maintaining camera synchronization between the two. When a user clicks in the Cesium scene, the screen coordinates of that point are passed to the Three.js renderer for Raycaster ray detection. After Three.js picks up the specific object, it parses a three-level unique identifier (tower ID - industry code - layer ID) from its user data (userData), and then returns this identifier and the event to the unified event bus in the Cesium layer for processing. The significance is that, without the user's awareness, interactive events occurring in different rendering engines are normalized, ensuring that whether clicking an icon on a map or clicking a bolt on a high-resolution model, the system can understand the user's intent in a unified way (through the three-level ID) and trigger subsequent business logic.

[0035] The blending management method for hybrid rendering is as follows: The core module, the "Scene Fusion Management Module," is responsible for the collaboration between Cesium and the embedded Three.js instance. It maintains a global scene-camera-object mapping table. Coordinate Transformation: When a high-resolution BIM model (using a local coordinate system) needs to be placed at a specific latitude and longitude in the Cesium world, this module uses Cesium.Transforms to perform matrix calculations to transform from WGS84 longitude / latitude / altitude to ECEF coordinates, and then to Three.js world coordinates. State Synchronization: When the Cesium camera moves or rotates, the management module calculates the corresponding transformation matrix in real time and drives the Three.js camera to update synchronously, ensuring that the scene seen from both perspectives is completely consistent. Its significance lies in solving the problem of fusion between geographic space and local model space, enabling the detailed model rendered by Three.js to be accurately "placed" on the correct position on the Earth's surface, just like native Cesium entities, and displayed correctly as the viewpoint moves. It is the technological cornerstone for achieving a seamless experience of "macro-Earth + micro-model."

[0036] The preferred embodiments disclosed in this invention are merely illustrative examples of feasible implementation methods and are not intended to exhaustively cover all technical details of the invention, nor do they constitute a limitation on the scope of protection of this invention. In practical applications, those skilled in the art can make appropriate adjustments, combinations, or substitutions to the methods or systems described in these embodiments based on specific production conditions, equipment configurations, and process requirements, without departing from the core concept of this invention. For example, the acquisition method, data processing algorithm, control threshold, or specific implementation form of the execution unit can all be reasonably modified according to the actual situation.

[0037] Based on the above method, this disclosure also provides a layered rendering and interaction system for the Eiffel Tower model based on Cesium, including: a model splitting module, a database construction module, a model loading module, and a model interaction module; The model splitting module is used to split the Eiffel Tower model, add unique identifiers, and generate multi-level texture files. The database construction module is used to build the tower attribute database and standard object model library. The tower attribute database includes unique identifiers, industry type, geometric parameters, material information, core fields, and extended fields. The core fields of communication towers are operator, frequency band, and transmission power, while the extended fields of power towers are rated voltage and conductor type. The model loading module is used to dynamically render target layered models of different levels of detail according to priority, view distance, frame rate, and network bandwidth; the model interaction module is used to pick up the model, retrieve attribute data, and complete user interaction through a unique identifier.

[0038] 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; 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 this application.

Claims

1. A method for Cesium-based tower model layer rendering and interaction, characterized in that, include: After splitting the Eiffel Tower model into multiple layers, a unique identifier is added to each layer, and texture files of different levels of detail are generated. A tower attribute database is constructed to store attribute data of models at each level. The tower attribute database establishes the association between tower attribute data and models at each level through unique identifiers. Build a standard physical model library to store layered templates for iron towers in various industries; When loading the tower model, after selecting the target layered model from the standard object model library, the target layered model with different levels of detail is rendered using the texture file based on the line of sight, frame rate and network bandwidth. When picking a tower model, the target tower model is selected by a unique identifier. At the same time, the attribute data of each target layer model is obtained from the tower attribute database and displayed in the interactive area to realize information interaction with the user.

2. The method of claim 1, wherein, The multiple hierarchical models include: Basic layer, main structure layer, industry-specific layer, and identification layer; The unique identifier is: Tower ID - Industry Code - Hierarchical ID.

3. The method of claim 1, wherein, The tower attributes in the tower attribute database include: unique identifier, industry type, geometric parameters, material information, core fields, and extended fields; When the tower is a communication tower, the core fields include: operator, frequency band, and transmission power; When the tower is a power tower, the extended fields include: rated voltage and conductor type.

4. The method for layered rendering and interaction of the Eiffel Tower model based on Cesium according to claim 1, characterized in that, When loading the tower model, the layered models are loaded according to priority order. The priorities, from highest to lowest, are: main structure layer, industry-specific layer, basic layer, and identification layer.

5. The method for layered rendering and interaction of a Cesium-based Eiffel Tower model according to claim 2, characterized in that, When rendering hierarchical target models of varying detail based on view distance: Obtain the camera coordinates of Cesium and calculate the distance d between it and the center point of the tower; When the distance d is greater than the first distance threshold, the main structure layer model is loaded with the first level of refinement. When the second distance threshold ≤ distance d ≤ the first distance threshold, the main structure layer is loaded with the second level of fineness, the basic layer and the corresponding industry-specific layer are loaded with the first level of fineness; When the distance d is less than the second distance threshold, all levels of the model are loaded with the third level of refinement. Among them, the first level of refinement is less than the second level of refinement, which is less than the third level of refinement.

6. The method for layered rendering and interaction of a Cesium-based Eiffel Tower model according to claim 1, characterized in that, When picking up the tower model, the Cesium ray detection mechanism is used, and the tower model is picked up by filtering through a unique identifier.

7. The method for layered rendering and interaction of the Eiffel Tower model based on Cesium according to claim 2, characterized in that, When rendering hierarchical target models of varying detail based on frame rate: If the rendering frame rate is lower than the first frame rate threshold, reduce the model rendering detail and hide the identifier layer and some industry-specific layer models. If the rendering frame rate is higher than the second frame rate threshold, restore the model rendering detail and display the full-level model.

8. The method for layered rendering and interaction of the Eiffel Tower model based on Cesium according to claim 1, characterized in that, The step of retrieving attribute data for each target hierarchical model from the tower attribute database and displaying it in the interactive area to achieve information interaction with the user includes: A quadtree spatial index is constructed for the tower model using planar coordinates. Only tower data from the specified industry that falls within the current viewport range is loaded and displayed in the interactive area.

9. A Cesium-based tower model layer rendering and interaction system, characterized in that, include: The model splitting module is used to split the Eiffel Tower model into multiple layers, add a unique identifier to each layer, and generate texture files with different levels of detail. The database construction module is used to build a tower attribute database to store attribute data of models at each level. The tower attribute database establishes the association between tower attribute data and models at each level through unique identifiers. The module also builds a standard object model library to store hierarchical templates for towers in various industries. The model loading module is used to select a target layered model from the standard object model library when loading the tower model, and then render target layered models of different levels of detail using the texture file based on the line of sight, frame rate and network bandwidth. The model interaction module is used to select the target tower model by a unique identifier when picking a tower model. At the same time, it retrieves the attribute data of each target layer model from the tower attribute database and displays it in the interaction area to realize information interaction with the user.

10. The system according to claim 8, characterized in that, The tower attributes in the tower attribute database include: unique identifier, industry type, geometric parameters, material information, core fields, and extended fields; When the tower is a communication tower, the core fields include: operator, frequency band, and transmission power; When the tower is a power tower, the extended fields include: rated voltage and conductor type.

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