Real-time Rendering Method and System for Dynamic 3D Simulation Images Based on Electronic Chart

Abstract

The present invention relates to the technical field of image processing, and particularly to a real-time rendering method and system for dynamic three-dimensional simulation images based on electronic nautical charts. The method includes: acquiring two-dimensional electronic nautical chart data and dynamic real-time data; generating three-dimensional simulation images based on the acquired two-dimensional electronic nautical chart data and performing real-time rendering on the obtained three-dimensional simulation images; dynamically adjusting the rendering priority of key three-dimensional simulation images during rendering; updating the three-dimensional simulation images and dynamically rendering them after receiving the dynamic real-time data; the two-dimensional electronic nautical chart data includes geographic coordinates, water depth data, channel data, shoreline data, obstacle data, and object attribute data; the object attribute data includes object type, object height data, and object hierarchy data; the dynamic real-time data includes update data of the two-dimensional electronic nautical chart and maritime notice information.

Description

Technical Field

[0001] The present invention relates to the technical field of image processing, and particularly to a method and system for real-time rendering of dynamic three-dimensional simulation images based on electronic nautical charts. Background Art

[0002] An Electronic Navigational Chart (ENC) is a digital nautical chart used for modern ship navigation. It replaces traditional paper charts and integrates real-time data through electronic devices (such as an Electronic Chart Display and Information System, ECDIS), significantly improving navigation safety and efficiency.

[0003] Through data fusion (supplementing elevation and models) and coordinate transformation, a three-dimensional electronic nautical chart can be generated based on a two-dimensional electronic nautical chart. For example, the open-source three-dimensional earth engine CesiumJS supports loading electronic nautical chart data (such as in GeoJSON format) and generating a three-dimensional ocean scene in combination with terrain services. ESRI ArcGIS Pro: Achieves three-dimensional visualization of the seabed through the fusion of Bathymetric Attributed Grid (BAG) data and ENC. Professional nautical simulators Polaris and Navi-Trainer integrate three-dimensional visual scenes and electronic nautical chart data.

[0004] When rendering three-dimensional simulation images in a three-dimensional scene, the technical ideas of the existing technologies mainly focus on: separating styles from spatial data, improving efficiency by pre-querying the display style library and decoupling attribute parsing and graphic rendering; or processing through coordinate transformation in layers, that is, phased transformation (geographic → planar → screen) to reduce the real-time calculation complexity; and significantly reducing the number of drawing commands by using instruction merging and dynamic clipping.

[0005] However, it does not consider how to optimize the rendering process of the electronic nautical chart in a three-dimensional scene in the case of the update of the two-dimensional electronic nautical chart version and the receipt of maritime notices; and the situation of dynamically rendering objects during autonomous navigation. Summary of the Invention

[0006] The present invention dynamically adjusts the rendering priority of key three-dimensional simulation images through dynamic object criticality scoring to ensure the smooth rendering of three-dimensional images.

[0007] The technical solution proposed by the present invention is: A method for real-time rendering of dynamic three-dimensional simulation images based on an electronic nautical chart, the method comprising:

[0008] Obtaining two-dimensional electronic nautical chart data and dynamic real-time data;

[0009] Generate a 3D simulation image based on the acquired 2D electronic chart data, and perform real-time rendering on the obtained 3D simulation image; Dynamically adjust the rendering priority of key 3D simulation images during rendering;

[0010] After receiving dynamic real-time data, update the 3D simulation image and perform dynamic rendering;

[0011] The 2D electronic chart data includes geographic coordinates, water depth data, waterway data, shoreline data, obstacle data, and object attribute data;

[0012] The object attribute data includes object type, object height data, and object hierarchy data;

[0013] The dynamic real-time data includes update data of the 2D electronic chart and maritime notice information.

[0014] Preferably, the generating a 3D simulation image based on the acquired 2D electronic chart data includes:

[0015] Convert the water depth data in the 2D electronic chart data into grid elevation points, and generate a continuous 3D seabed surface by combining with an interpolation algorithm;

[0016] Generate a shoreline 3D terrain by combining the shoreline data in the 2D electronic chart data with the digital elevation model DEM of surface buildings and facilities;

[0017] Generate an object 3D display model according to the object attribute data;

[0018] Convert the geographic coordinate longitude and latitude into a local coordinate system supported by the 3D engine, and correct the projection deformation through the UTM zoning algorithm;

[0019] Project the dynamic position of the ship, i.e., AIS data, into the local coordinate system;

[0020] The performing real-time rendering on the obtained 3D simulation image includes:

[0021] Load ocean material data, ship texture data, vertex shader, and fragment shader;

[0022] Layer by object type, including terrain layer, dynamic object layer, and UI layer;

[0023] Detect whether the bounding box of the object 3D display model intersects with the view frustum;

[0024] Select the LOD level according to the distance from the object to the camera;

[0025] Batch submit transformation matrices for similar objects, perform lighting calculations through the Phong lighting model, generate depth maps and use them for real-time shadow calculations.

[0026] Preferably, after receiving the dynamic real-time data, updating the 3D simulation image and dynamically rendering it includes:

[0027] Obtaining update data, including incremental files in IHO S-57 / S-101 format or JSON / XML messages of maritime notices;

[0028] Extracting the range of the updated area, object type, longitude and latitude coordinates, and object attribute data from the update data;

[0029] Using differential coding to extract the transformed part of the update data relative to the original 2D nautical chart data to avoid parsing all data;

[0030] Performing object display style matching based on the object type, that is, querying the IHO ECDIS display library according to the object data to obtain the corresponding 3D display model as the new object model;

[0031] Converting the longitude and latitude of the new object model into local coordinates supported by the 3D engine; updating the original object model with the new object model;

[0032] If the materials of the new object models are the same, merging the drawing instructions of the new object models into a single batch for submission to reduce the number of GPU calls;

[0033] For the same new object models, using the instanced rendering algorithm for batch processing.

[0034] Preferably, the real-time rendering of the obtained 3D simulation image further includes:

[0035] Highlighting the key features of the 3D simulation image of key objects and avoiding redundant calculations, specifically including:

[0036] Defining semantic importance based on object attributes, that is, setting object priority weights based on object data ;

[0037] Based on the object movement speed , and the distance from the viewpoint as well as the interaction frequency , performing object criticality evaluation, that is, object criticality scoring ; where respectively represent weight coefficients, respectively represent the maximum speed, maximum viewing distance, and maximum interaction frequency;

[0038] Obtaining the 3D simulation images of objects related to the navigation task in the current navigation task, and the objects related to the navigation task include obstacles in the waterway, waterway lines, and ships in the same waterway;

[0039] If , then it is determined that the corresponding object label is a key object label; among them, represents the criticality evaluation threshold;

[0040] All object labels that meet the condition are sorted in descending order according to the object label criticality score to form a priority sequence; and the first K object labels are selected as key object labels for dynamic rendering, and the value of K is dynamically adjusted according to the GPU memory.

[0041] Preferably, the real-time rendering of the obtained three-dimensional simulation image further includes:

[0042] During the rendering of the selected K object labels, the highest precision LOD is forced to be used, and the view distance downgrading is prohibited; that is:

[0043] The th object label's precision ;

[0044] In the fragment shader, edge detection and color overlay are added, and a spotlight effect is added to the key object label to improve its visual contrast, that is ; among them, respectively represent the light source direction vector and the surface normal of the key object label; represents the light intensity coefficient; ; represents the basic visual contrast;

[0045] Use MSAA 4× anti-aliasing and HDR algorithm to independently render the key object label;

[0046] Render non-key object labels using a low sampling rate and a simplified shader;

[0047] Perform parallel task allocation for the GPU and CPU, that is,

[0048] The screening of key object labels and the processing of key object label data use CPU thread 1;

[0049] The LOD calculation of non-key object labels uses CPU thread 2;

[0050] The rendering and light enhancement of key object labels use the GPU Compute Shader, and a fixed thread area is allocated to store the three-dimensional display model of key object labels;

[0051] Compress the texture of non-key object labels using the BC7 compression algorithm, and use the lossless RGBA32 format for the texture of key object labels.

[0052] Preferably, the real-time rendering of the obtained three-dimensional simulation image further includes:

[0053] Dynamically schedule computing resources based on priorities, specifically including:

[0054] Based on the priority sequence, reserve 70% of the GPU time for the rendering of key objects per frame;

[0055] If the rendering time is greater than the target frame time, preferentially reduce the LOD level of non-key objects;

[0056] Prohibit detecting whether the bounding box of the 3D model of the key object intersects with the view frustum, that is, disable the view frustum culling operation for the key object;

[0057] When detecting whether the bounding box of the 3D model of the non-key object intersects with the view frustum, expand the view frustum culling range to , where represents the view frustum culling range of non-key objects.

[0058] Preferably, dynamically adjusting the rendering priority of the key 3D simulation image during rendering includes:

[0059] Define the 3D display model of the key object as the key 3D simulation image;

[0060] Obtain the route information, divide the route into multiple waypoints, that is, the route can be represented as a set of multiple waypoints;

[0061] Let the route be , divide the route path into multiple route segments ; where represents the number of waypoints, ;

[0062] Calculate the navigation angle and length of each route segment, set the path influence radius , and only consider the relevance between the key objects within the path influence radius and the path;

[0063] Optimize the priority score calculation process, and propose a dynamic priority calculation process, including:

[0064] Set the vertical distance attenuation function , where represents the Gaussian attenuation coefficient, represents the shortest distance from the object to the route segment;

[0065] Set the direction consistency score ; where represents the angle between the object and the current waterway;

[0066] Then, the dynamic object criticality score associated with the route , respectively represent dynamic weight coefficients, represent semantic priorities, and the semantic priorities are set based on object types;

[0067] Based on the dynamic object criticality scores associated with the route, perform dynamic screening and resource allocation of objects, specifically including:

[0068] Select and objects as critical objects, where respectively represent a distance-related threshold and an angle-related threshold;

[0069] Arrange the dynamic object criticality scores associated with the route in ascending order to form a dynamic object priority sequence. Only the first critical objects are rendered with full precision per frame;

[0070] If , the corresponding object is retained for rendering regardless of whether it is within the path influence radius;

[0071] Allocate independent GPU time for the rendering of critical objects.

[0072] Preferably, the arranging the dynamic object criticality scores associated with the route in ascending order to form a dynamic object priority sequence, and only the first critical objects are rendered with full precision per frame, includes:

[0073] During rendering, according to the dynamic object criticality scores associated with the route, add luminous borders with different luminous intensities to the first critical objects, and maintain the highest LOD level, that is, the LOD0 level;

[0074] Generate direction arrows at the positions of each critical object, and the direction arrows point to the next waypoint.

[0075] The present invention also provides a real-time rendering system for dynamic 3D simulation images based on an electronic chart, including a processor, a memory and a communication module connected to the processor. The system is used to execute the real-time rendering method for dynamic 3D simulation images based on the electronic chart.

[0076] The present invention also provides a computer-readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the real-time rendering method for dynamic 3D simulation images based on the electronic chart.

[0077] Advantages of the present invention:

[0078] In the present invention, when the two-dimensional electronic chart is updated or a maritime notice is received, the electronic chart in the three-dimensional scene is updated in real time. Through incremental data processing and dynamic rendering optimization, the changes in the chart can be quickly responded to, and a smooth interaction experience can be achieved.

[0079] 2. In the present invention, during dynamic rendering optimization, through path correlation analysis and in combination with the priority (criticality score of dynamic objects associated with the shipping lane), the objects related to the shipping lane are dynamically highlighted in the three-dimensional scene, and the objects with the highest priority are retained, so as to balance navigation guidance and the display of the overall chart information and adapt to scenarios with high real-time requirements such as automatic ship navigation. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 It is a flowchart of the real-time rendering method of the dynamic three-dimensional simulation image based on the electronic chart according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0081] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious deformations. The basic principles defined in the following description can be applied to other implementation schemes, deformation schemes, improvement schemes, equivalent schemes, and other technical schemes that do not deviate from the spirit and scope of the present invention.

[0082] It can be understood that the term "a" should be understood as "at least one" or "one or more". That is, in one embodiment, the number of an element can be one, while in other embodiments, the number of the element can be multiple. The term "a" cannot be understood as a limitation on the number.

[0083] Embodiment 1:

[0084] Refer to Figure 1 , the technical solution provided by the present invention is: a real-time rendering method of a dynamic three-dimensional simulation image based on an electronic chart, including the following steps:

[0085] Step 1: Obtain two-dimensional electronic chart data and dynamic real-time data;

[0086] Step 2: Generate a three-dimensional simulation image based on the obtained two-dimensional electronic chart data, and perform real-time rendering on the obtained three-dimensional simulation image; dynamically adjust the rendering priority of the key three-dimensional simulation images during rendering.

[0087] Step 3: After receiving the dynamic real-time data, update the three-dimensional simulation image and perform dynamic rendering.

[0088] Among them, generating a three-dimensional simulation image based on the obtained two-dimensional electronic chart data in Step 2 includes the following steps:

[0089] Convert the water depth data in the two-dimensional electronic chart data into grid elevation points, and generate a continuous three-dimensional seabed surface in combination with the interpolation algorithm;

[0090] Generate a three-dimensional shoreline terrain by combining the shoreline data in the two-dimensional electronic chart data with the digital elevation model (DEM) of surface buildings and facilities;

[0091] Generate a three-dimensional display model of the object according to the object attribute data;

[0092] Convert the geographical coordinates (longitude and latitude) into a local coordinate system supported by the three-dimensional engine, and correct the projection deformation through the UTM zoning algorithm;

[0093] Project the dynamic position of the ship, i.e., the AIS data, into the local coordinate system.

[0094] Among them, the real-time rendering of the obtained three-dimensional simulation image in step 2 includes the following steps:

[0095] Load ocean material data, ship texture data, vertex shaders, and fragment shaders;

[0096] Layer by object type, including a terrain layer, a dynamic object layer, and a UI layer; read the object type (including lighthouses, buoys, obstacles, ships, etc.) from the standard electronic chart file (ENC)

[0097] Detect whether the bounding box of the three-dimensional display model of the object intersects with the frustum; that is, perform frustum culling operation,

[0098] Select the LOD level according to the distance from the object to the camera; for example, when the distance from the object to the camera is less than 1000 meters, the LOD level is LOD0, and the number of triangles is 10000; when the distance from the object to the camera is in the range of 1000 meters to 1500 meters, the LOD level is LOD1, and the number of triangles is 2000; when the distance from the object to the camera is greater than 1500 meters, the LOD level is LOD2, and the number of triangle data is 500.

[0099] Batch submit transformation matrices for objects of the same type, perform lighting calculations through the Phong lighting model, generate depth maps and use them for real-time shadow calculations.

[0100] Among them, in step 2, dynamically adjusting the rendering priority of the key three-dimensional simulation image during rendering includes the following steps:

[0101] Screen out key objects, highlight the key features of the three-dimensional simulation images of key objects, and avoid redundant calculations, specifically including:

[0102] Define semantic importance based on object attributes, that is, set object priority weights based on object data ; For example, when the object is an obstacle, the priority weight is 0.8, and when the object is a buoy, the priority weight is 0.6.

[0103] Based on the moving speed of the object , the distance from the viewpoint and the interaction frequency , perform a criticality evaluation of the object, that is, the criticality score of the object ; Among them, respectively represent the weight coefficients, respectively represent the maximum speed, the maximum viewing distance, and the maximum interaction frequency;

[0104] Obtain the three-dimensional simulation images of the objects related to the navigation task in the current navigation task. The objects related to the navigation task include obstacles in the waterway, waterway lines, and ships in the same waterway;

[0105] If , then determine that the corresponding object is a critical object; among them, represents the criticality evaluation threshold;

[0106] Arrange all the objects that meet the condition in descending order according to the criticality score of the object to form a priority sequence; and select the top K objects as critical objects for dynamic rendering, and the value of K is dynamically adjusted according to the GPU memory.

[0107] During the rendering of the selected K objects, force the use of the highest precision LOD and prohibit the viewing distance from being downgraded to highlight the key features (contrast, texture, etc.) of the three-dimensional simulation images of the critical objects; that is:

[0108] The th object's precision ;

[0109] In the fragment shader, add edge detection and color overlay, and add a spotlight effect to the critical objects to improve their visual contrast, that is ; Among them, respectively represent the light source direction vector and the surface normal of the critical object; represents the light intensity coefficient; ; represents the basic visual contrast;

[0110] Use MSAA 4× anti-aliasing and HDR algorithms to independently render the critical objects;

[0111] Render the non-critical objects using a low sampling rate and a simplified shader;

[0112] Allocate parallel tasks to the GPU and the CPU, that is,

[0113] The screening of key landmarks and the processing of key landmark data use CPU thread 1;

[0114] The LOD calculation of non-key landmarks uses CPU thread 2;

[0115] The rendering and lighting enhancement of key landmarks use the GPU Compute Shader, allocate a fixed thread area, and store the 3D display model of key landmarks;

[0116] The texture of non-key landmarks is compressed using the BC7 compression algorithm, and the texture of key landmarks uses the lossless RGBA32 format.

[0117] Among them, step 3 can be implemented through the following steps:

[0118] Step 3.1: Obtain updated data, including incremental files in IHO S-57 / S-101 format or JSON / XML messages of maritime notices;

[0119] Step 3.2: Extract the range of the updated area, landmark type, longitude and latitude coordinates, and landmark attribute data from the updated data;

[0120] Step 3.3: Use differential coding to extract the transformed part of the updated data relative to the original 2D nautical chart data, avoiding full-scale data parsing;

[0121] Step 3.4: Perform landmark display style matching based on the landmark type, that is, query the IHO ECDIS display library according to the landmark data to obtain the corresponding 3D display model as the new added landmark model;

[0122] Step 3.5: Convert the longitude and latitude of the new added landmark model into local coordinates supported by the 3D engine; use the new added landmark model to update the original landmark model;

[0123] Step 3.6: If the materials of the new added landmark models are the same, merge the drawing instructions of the new added landmark models into a single batch for submission to reduce the number of GPU calls;

[0124] For the same new added landmark models, use the instanced rendering algorithm for batch processing.

[0125] Embodiment 2:

[0126] In scenarios with high real-time requirements such as ship automatic navigation and UAV route monitoring, in order to balance navigation guidance and global information display, only key landmarks associated with the navigation path are rendered. That is, through path proximity analysis, the landmarks related to the route are dynamically highlighted in the 3D scene, while high-priority targets are retained.

[0127] Based on Embodiment 1, the following technical solutions are proposed:

[0128] Dynamically adjust the rendering priority of key 3D simulation images during rendering, including:

[0129] Define the 3D display model of key objects as key 3D simulation images;

[0130] Obtain route information, divide the route into multiple waypoints, that is, the route can be represented as a set of multiple waypoints;

[0131] Let the route be , divide the route path into multiple segments ; where represents the number of waypoints, ;

[0132] Calculate the navigation angle and length of each segment, set the path influence radius , and only consider the relevance between key objects within the path influence radius and the path;

[0133] Optimize the priority score calculation process, and propose a dynamic priority calculation process, including:

[0134] Set the vertical distance attenuation function , where represents the Gaussian attenuation coefficient, represents the shortest distance from the object to the segment;

[0135] Set the direction consistency score ; where represents the angle between the object and the current waterway;

[0136] Then, the dynamic object criticality score associated with the route , respectively represent the dynamic weight coefficients, represents the semantic priority, and the semantic priority is set based on the object type;

[0137] Based on the dynamic object criticality score associated with the route, perform dynamic screening and resource allocation of objects, specifically including:

[0138] Select and objects as key objects, where respectively represent the distance-related threshold and the angle-related threshold;

[0139] Arrange the dynamic object criticality scores associated with the route in ascending order to form a dynamic object priority sequence, and only perform full-precision rendering on the first key objects per frame; specifically:

[0140] Perform hierarchical rendering:

[0141] The first layer: Render path-associated landmarks. That is, according to the criticality scores of dynamic landmarks associated with the route, add luminous borders with different luminous intensities to the first several critical landmarks (the brightness of the luminous border varies with the level of the criticality score of the dynamic landmark). And, generate direction arrows at the position of each critical landmark, and the direction arrow points to the next waypoint.

[0142] The second layer: Render high-priority landmarks, lock the LOD and apply depth offset, that is, maintain the highest LOD level of the critical landmarks, that is, the LOD0 level.

[0143] The third layer: Simplify the rendering of other landmarks, that is, non-critical landmarks are rendered in a low LOD and without special effects (luminous border, arrow).

[0144] In this embodiment, performance monitoring can also be performed as needed:

[0145] Statistical rendering time for each layer, dynamically adjust the maximum number of landmarks rendered per frame and to maintain the frame rate; allocate independent GPU time for the rendering of critical landmarks.

[0146] And, if , the corresponding landmark is retained for rendering regardless of whether it is within the path influence radius.

[0147] The present invention also provides a real-time rendering system for dynamic three-dimensional simulation images based on an electronic nautical chart, including a processor, and a memory and a communication module connected to the processor. The system is used to execute the real-time rendering method for dynamic three-dimensional simulation images based on the electronic nautical chart.

[0148] The present invention also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the real-time rendering method for dynamic three-dimensional simulation images based on the electronic nautical chart.

[0149] Embodiments disclosed in the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. Embodiments disclosed in the present invention include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program codes for executing the methods shown in the flowcharts. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part, and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), the above-mentioned functions defined in the method of the present invention are executed. It should be noted that the computer-readable medium in the present invention can be a computer-readable signal medium or a computer-readable storage medium or any combination of the two. The computer-readable storage medium can, for example, but not be limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium can include, but not be limited to: an electrical connection with one or more wire segments, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present invention, the computer-readable storage medium can be any tangible medium that contains or stores a program, and the program can be used by or combined with an instruction execution system, apparatus, or device. In the present invention, the computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries the computer-readable program code. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The computer-readable signal medium can also be any computer-readable medium other than the computer-readable storage medium, and the computer-readable medium can send, propagate, or transmit a program for use by or combined with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted by any appropriate medium, including but not limited to: wireless segments, wire segments, optical cables, RF, etc., or any suitable combination of the above.

[0150] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a part of code, which contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, as well as combinations of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0151] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments. Without departing from the said principles, any changes or modifications can be made to the embodiments of the present invention.

Claims

1. A real-time rendering method for dynamic three-dimensional simulation images based on an electronic chart, characterized in that The method includes: Obtaining two-dimensional electronic chart data and dynamic real-time data; Generating a three-dimensional simulation image based on the obtained two-dimensional electronic chart data, and performing real-time rendering on the obtained three-dimensional simulation image; dynamically adjusting the rendering priority of key three-dimensional simulation images during rendering; After receiving the dynamic real-time data, updating the three-dimensional simulation image and dynamically rendering it; The two-dimensional electronic chart data includes geographic coordinates, water depth data, waterway data, shoreline data, obstacle data, and object attribute data; The object attribute data includes object type, object height data, and object level data; The dynamic real-time data includes update data of the two-dimensional electronic chart and maritime notice information; The performing real-time rendering on the obtained three-dimensional simulation image includes: Highlighting the key features of the three-dimensional simulation images of key objects and avoiding redundant calculations, specifically including: Define semantic importance based on the attributes of the object markers, that is, set the priority weights of the object markers based on the object marker data ; Based on the moving speed of the object marker , the distance from the viewpoint and the interaction frequency , conduct a criticality evaluation of the object marker, that is, the criticality score of the object marker ; among them, respectively represent the weight coefficients, respectively represent the maximum speed, the maximum viewing distance and the maximum interaction frequency; Obtaining the three-dimensional simulation images of objects related to the navigation task in the current navigation task, and the objects related to the navigation task include obstacles in the waterway, waterway lines, and ships in the same waterway; If , then determine that the corresponding object label is a key object label; among them, represents the critical evaluation threshold; Arrange all the targets that meet the conditions in descending order according to the criticality score of the targets to form a priority sequence; and select the top K targets as critical targets for dynamic rendering, where the value of K is dynamically adjusted according to the GPU memory; The dynamically adjusting the rendering priority of key three-dimensional simulation images during rendering includes: Defining the three-dimensional display model of the key object as the key three-dimensional simulation image; Optimizing the priority score calculation process and proposing a dynamic priority calculation process, including: Set the vertical distance attenuation function , where represents the Gaussian attenuation coefficient, represents the shortest distance from the target to the flight segment; Set direction consistency score ; where represents the angle between the object and the current waterway; Then, the criticality score of the dynamic object marker associated with the route , respectively represent the dynamic weight coefficients, represents the semantic priority, and the semantic priority is set based on the object marker type; Performing dynamic screening and resource allocation of objects based on the dynamic object criticality score associated with the route, specifically including: Select and of the object markers as the key object markers, where respectively represent the distance-related threshold and the angle-related threshold; Sort the critical scores of dynamic landmarks associated with the route in ascending order to form a dynamic landmark priority sequence, and only fully render the first critical landmarks per frame; If , the corresponding object markers are retained for rendering regardless of whether they are within the path influence radius; Allocating independent GPU time for the rendering of key objects.

2. The real-time rendering method of dynamic three-dimensional simulation images based on an electronic chart according to claim 1, characterized in that The generating a three-dimensional simulation image based on the obtained two-dimensional electronic chart data includes: Converting the water depth data in the two-dimensional electronic chart data into grid elevation points, and generating a continuous three-dimensional seabed surface in combination with the interpolation algorithm; Generating a three-dimensional shoreline terrain by combining the shoreline data in the two-dimensional electronic chart data with the digital elevation model DEM of surface buildings and facilities; Generating a three-dimensional display model of the object according to the object attribute data; Converting the geographic coordinate longitude and latitude into a local coordinate system supported by the three-dimensional engine, and correcting the projection deformation through the UTM zoning algorithm; Projecting the dynamic position of the ship, i.e., AIS data, into the local coordinate system; The performing real-time rendering on the obtained three-dimensional simulation image includes: Loading ocean material data, ship texture data, vertex shaders, and fragment shaders; Layering according to the object type, including a terrain layer, a dynamic object layer, and a UI layer; Detecting whether the bounding box of the three-dimensional display model of the object intersects with the view frustum; Selecting the LOD level according to the distance from the object to the camera; Batch submitting transformation matrices for objects of the same type, performing lighting calculations through the Phong lighting model, generating a depth map and using it for real-time shadow calculations.

3. The real-time rendering method of dynamic three-dimensional simulation images based on an electronic chart according to claim 2, wherein The updating the three-dimensional simulation image and dynamically rendering it after receiving the dynamic real-time data includes: Obtaining update data, including incremental files in IHO S-57 / S-101 format or JSON / XML messages of maritime notices; Extracting the range of the updated area, object type, longitude and latitude coordinates, and object attribute data from the update data; Using differential coding to extract the transformed part of the update data relative to the original two-dimensional chart data, avoiding full-scale data parsing; Match the display style of object markers based on the object marker type, that is, query the IHO ECDIS display library according to the object marker data to obtain the corresponding 3D display model as the newly added object marker model; Convert the longitude and latitude of the newly added object marker model into local coordinates supported by the 3D engine; update the original object marker model with the newly added object marker model; If the materials of the newly added object marker models are the same, merge the drawing instructions of the newly added object marker models into a single batch for submission to reduce the number of GPU calls; For the same newly added object marker models, use the instanced rendering algorithm for batch processing.

4. The real-time rendering method of dynamic 3D simulation images based on electronic nautical charts according to claim 3, characterized in that, The real-time rendering of the obtained 3D simulation image further includes: During the rendering process of the selected K object markers, force the use of the highest precision LOD and prohibit view distance degradation; that is: The accuracy of the ; In the fragment shader, edge detection and color overlay are added, and a spotlight effect is added to the key landmarks to improve their visual contrast, that is ; where respectively represent the light source direction vector and the surface normal of the key landmark; represents the light intensity coefficient; ; Use the MSAA 4× anti-aliasing and HDR algorithms to independently render the key object markers; Render the non-key object markers with a low sampling rate and a simplified shader; Allocate parallel tasks to the GPU and CPU, that is, Use CPU thread 1 for the screening of key object markers and the processing of key object marker data; Use CPU thread 2 for the LOD calculation of non-key object markers; Use the GPU Compute Shader for the rendering and lighting enhancement of key object markers, and allocate a fixed thread area to store the 3D display models of key object markers; Compress the textures of non-key object markers using the BC7 compression algorithm, and use the lossless RGBA32 format for the textures of key object markers.

5. The real-time rendering method of dynamic three-dimensional simulation images based on electronic nautical charts according to claim 4, characterized in that, The real-time rendering of the obtained 3D simulation image further includes: Dynamically schedule computing resources based on priorities, specifically including: Reserve 70% of the GPU time for the rendering of key object markers per frame based on the priority sequence; If the rendering time is greater than the target frame time, preferentially reduce the LOD level of non-key object markers; Prohibit detecting whether the bounding box of the 3D model of the key object marker intersects with the view frustum, that is, disable the view frustum culling operation for key object markers; When detecting whether the bounding box of the 3D model of non-critical objects intersects with the viewing frustum, expand the viewing frustum culling range to , where represents the viewing frustum culling range of non-critical objects.

6. The real-time rendering method of dynamic three-dimensional simulation image based on electronic chart according to claim 5, characterized in that The dynamic adjustment of the rendering priority of the key 3D simulation image during rendering further includes: Obtain the route information and divide the route into multiple waypoints, that is, the route can be represented as a set of multiple waypoints; Set the route , and divide the route path into multiple segments ; among them represents the number of waypoints, ; Calculate the sailing angle of each flight segment and length , set the path influence radius , and only consider the relevance between key landmarks within the path influence radius and the path.

7. The real-time rendering method of dynamic three-dimensional simulation images based on an electronic chart according to claim 6, characterized in that, The dynamic object criticality scores associated with the route are sorted in ascending order to form a dynamic object priority sequence. Only the first key objects are rendered with full precision per frame, including: During rendering, according to the criticality score of dynamic landmarks associated with the route, different luminous borders with different luminous intensities are added to the first critical landmarks, and the highest LOD level, that is, the LOD0 level, is maintained; Generate a direction arrow at each key object marker position, and the direction arrow points to the next waypoint.

8. A real-time rendering system for dynamic three-dimensional simulation images based on an electronic chart, comprising a processor, a memory and a communication module connected to the processor, characterized in that, The system is used to execute the real-time rendering method of the dynamic 3D simulation image based on the electronic chart described in any one of the above claims 1-7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the real-time rendering method of the dynamic 3D simulation image based on the electronic chart described in any one of the above claims 1-7.

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