A multi-body-oriented space environment data three-dimensional coordinate adaptive conversion and rendering method and system

Abstract

The application discloses a kind of multi-sky-oriented space environment data three-dimensional coordinate adaptive conversion and rendering method and system, it is related to space environment data visualization technical field.The application establishes the scene radius and real radius of each sky by establishing sky parameter registry, proposes double radius parameter adaptive coordinate conversion formula, so that the same set of conversion logic adapts to earth, moon, Mars and other arbitrary sky.Using three-dimensional scene graph parent-child level mechanism, particle system is mounted as sky grid subnode, and data points automatically follow sky movement.The application proposes a dynamic near clipping plane adaptive algorithm based on sight distance, and solves the problem of small sky invisibility through double camera synchronous setting strategy.Independent instantiation of multi-sky particle system and on-demand switching in single frame are realized.The application solves the technical problems of coordinate conversion and sky coupling, height mapping distortion and small sky invisibility in the prior art, and is suitable for three-dimensional visualization of multi-sky space environment model results.

Description

Technical Field

[0001] This invention relates to the field of space environment data visualization technology, specifically to a method and system for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies. Background Technology

[0002] With the widespread application of space environment models (such as the NRLMSIE-00 atmospheric model and the IRI ionospheric model), their calculation results are typically output in geographic coordinate system form. Each data point includes latitude, longitude, altitude above the celestial surface, and corresponding physical quantities (such as particle density). In space science research and aerospace engineering applications, overlaying this data onto the corresponding celestial surface and performing 3D visualization has become an important means of analyzing the distribution characteristics of the space environment and supporting mission decisions. Especially with the comprehensive display requirements involving multiple celestial bodies such as Earth, the Moon, and Mars, how to achieve intuitive expression of multi-source space environment data in a unified 3D environment has become an important direction for the development of current visualization technology.

[0003] However, existing technologies still have significant shortcomings in achieving 3D visualization of spatial environment data: First, the conversion from geographic coordinates to 3D Cartesian coordinates is usually strongly coupled with the radius parameters of specific celestial bodies (such as Earth), making it difficult to switch flexibly between different celestial bodies; second, the nonlinear scaling processing used in 3D scenes to adapt to multi-scale celestial bodies lacks an effective mapping mechanism with the height values ​​in the data based on real physical units, resulting in height ratio distortion in the visualization results; in addition, in scenes containing multiple celestial bodies with significant size differences, fixed camera near-cropping parameters can cause small-scale celestial bodies to fall entirely within the cropping range and fail to be displayed, seriously affecting the user's interactive experience.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, so as to solve the problems in the background art mentioned above.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, comprising the following steps: Construct a celestial parameter registry to record the configuration parameters for each celestial body to be visualized. Each parameter record includes the scene radius and the real radius, where the scene radius is the normalized display radius of the corresponding celestial body in the 3D scene, and the real radius is the physical radius of the corresponding celestial body. The latitude, longitude, and altitude of the input data points above the celestial body's surface are obtained. Based on the scene radius and real radius of the target celestial body, the altitude is normalized and mapped to the scene space to obtain the corresponding rendering distance. The three-dimensional Cartesian coordinates of the data points are then calculated based on the rendering distance. A corresponding particle data set is established for each celestial body, and the particle data set is mounted to the scene node of the corresponding celestial body according to three-dimensional Cartesian coordinates, so that the particle data set changes synchronously with the spatial transformation of the corresponding celestial body. When switching the viewpoint of the target celestial body, the minimum observation distance is calculated based on the scene radius of the target celestial body, and the near clipping surface parameters are adaptively calculated based on the minimum observation distance, while the near clipping surface parameters of the camera are updated. In response to the target celestial body switching command, the camera parameters are adjusted based on the updated near clipping plane parameters, and the camera viewpoint is associated with the scene node of the target celestial body. At the same time, the visibility state of the particle data set corresponding to different celestial bodies is switched to complete the rendering switching of multi-celestial body data.

[0007] Preferably, in a multi-celestial 3D scene, to unify the display parameters of celestial bodies of different scales, the display radius of the celestial bodies is normalized, and the steps are as follows: The original radius parameters of the celestial body to be processed are read, and these original radius parameters are used as inputs in subsequent calculations. The original radius parameter is square-rooted to perform nonlinear compression on the original scale. The square root result is proportionally calculated with a preset global scaling constant to obtain the corresponding scene radius value; The obtained scene radius is written into the parameter set as the celestial display scale parameter for subsequent coordinate transformation and rendering processes.

[0008] Preferably, the ratio between the square root operation and the global scaling constant is fixed in advance and kept consistent. The scene radius is stored in a structured form in the parameter set and the calculation rules are kept consistent when calling different celestial bodies, so as to limit the generation and usage of the display scale parameter.

[0009] Preferably, in the process of mapping space environment data, in order to establish the correspondence between altitude values ​​and celestial scales, the altitude of data points is proportionally converted, and the steps are as follows: Obtain the height value of the data point and the true radius parameter of the corresponding celestial body, and use both as calculation inputs; The height value is compared with the actual radius parameter to obtain the corresponding dimensionless ratio value; The height increment in the scene space is obtained by numerically mapping the scale value to the scene radius. The height increment is superimposed on the scene radius to form the radial distance parameter of the data point in the scene, which is then used in the 3D coordinate calculation.

[0010] Preferably, the mapping between the height value and the scene radius is calculated by square root transformation to increase the scene increment, and the ratio is adjusted by a global scaling constant to ensure that the height mapping of each celestial body is consistent, forming a unified radial distance parameter input for three-dimensional coordinate calculation, thereby achieving standardized processing of the height ratio between different celestial bodies.

[0011] Preferably, under the condition of switching between multiple celestial viewpoints, in order to achieve the matching between the camera clipping range and the celestial scale, the near-clipping surface parameters are dynamically calculated, and the steps are as follows: Obtain the corresponding scale parameters based on the scene radius of the target celestial body, and determine the minimum observation distance accordingly; The minimum observation distance is multiplied by a preset scaling factor to obtain candidate values ​​for the near cutting plane. The candidate values ​​are compared with a preset minimum threshold, and the maximum value is selected as the near-cutting plane parameter. The calculated near clipping plane parameters are written into the parameter sets of the rendering camera and the control camera, respectively, and the projection parameter update operation is triggered.

[0012] Preferably, when calculating the near clipping plane parameters, the preset scaling factor and minimum threshold are adjusted through configurable parameters, and the update operation is applied to all rendering camera and control camera instances to ensure that the clipping parameters of each camera remain synchronized and consistent during multi-celestial body switching.

[0013] Preferably, during the display of multi-celestial data and perspective switching, in order to coordinate the camera position and interactive control constraints, the relevant parameters are configured, and the steps are as follows: The minimum observation distance is obtained based on the scale parameters of the target celestial body, and this distance is used as a constraint reference value; The distance parameter in the interactive control is set, and its minimum value is limited to the minimum observation distance; The camera's three-dimensional position is assigned values ​​according to a preset spatial ratio to determine the viewing angle; After adjusting the camera position, the display state of the particle data set is switched, and the currently displayed object is updated.

[0014] Preferably, during the display of multi-celestial body data and the switching of perspectives, the adjustment of camera position is further restricted, requiring the camera to be mounted on the target celestial body node and the minimum distance parameter of the orbit controller to be updated synchronously. At the same time, the three-dimensional position of the camera is adjusted to form an oblique upward observation perspective. The visibility of the particle data set is updated according to the state of the target celestial body, so as to realize rapid switching between different celestial bodies and data synchronization management.

[0015] A 3D coordinate adaptive transformation and rendering system for multi-celestial body space environment data includes a celestial body parameter registration module, a coordinate transformation module, a scene graph management module, a camera adaptation module, and a rendering target switching module. The celestial body parameter registration module stores and manages the scene radius and actual radius of each celestial body, and provides parameter query based on celestial body identifiers; The coordinate transformation module receives the geographic coordinates of the data points and the target celestial body identifier, obtains the corresponding scene radius and real radius from the celestial body parameter registration module based on the celestial body identifier, and performs transformation processing on the geographic coordinates to obtain the corresponding three-dimensional Cartesian coordinates. The scene graph management module creates corresponding particle data sets for each celestial body, attaches the particle data sets to the scene nodes of the corresponding celestial body, and manages the display status of the particle data sets corresponding to each celestial body. The camera adaptive module calculates the minimum observation distance based on the scene radius of the target celestial body during the target celestial body switching process, and calculates the near clipping surface parameters based on the minimum observation distance, updates the camera's near clipping surface parameters, and adjusts the camera position and interactive control constraints at the same time. The rendering target switching module receives the target celestial body identifier and controls the display state of the particle data set corresponding to each celestial body based on the target celestial body identifier. It also adjusts the spatial relationship between the camera and the target celestial body and coordinates the camera adaptive module to complete parameter updates in order to realize rendering switching between different celestial bodies.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention proposes an adaptive coordinate transformation method with dual radius parameters, decoupling and co-modeling the scene radius and the real radius, achieving unified mapping of different celestial spatial data within the same transformation formula framework. This method avoids the hard-coded dependence on a single celestial radius parameter found in traditional techniques, giving the coordinate transformation logic good versatility and scalability. When introducing new celestial objects, only registration in the parameter system is required, without modifying the core algorithm, thus significantly reducing system maintenance costs and improving adaptability. It effectively solves the problem of strong coupling between coordinate transformation and specific celestial objects in existing technologies.

[0017] This invention, based on a scene graph parent-child hierarchical structure, establishes a subordinate relationship between particle data and corresponding celestial body nodes, enabling spatial data to automatically inherit the spatial transformation attributes of celestial bodies. Under this mechanism, the rotation and revolution behaviors of celestial bodies can be directly transmitted to the particle system without requiring frame-by-frame position updates for each data point, thus avoiding the performance overhead caused by redundant calculations. This hierarchical transmission-based processing method not only improves system operating efficiency but also enhances the spatial consistency between data and celestial bodies, making the visualization results more consistent with the laws of real physical motion.

[0018] This invention constructs a dynamic near-clipping plane adaptive algorithm based on view distance. By introducing parameter relationships related to celestial scale, it achieves real-time adjustment of near-clipping plane parameters. Furthermore, by combining this with a dual-camera synchronization strategy, it ensures that parameters remain consistent across different cameras during rendering, avoiding display anomalies caused by state overlap. This method effectively solves the problem of small celestial bodies failing to display in multi-scale scenes due to improper clipping plane settings, improving system stability and adaptability while maintaining rendering accuracy.

[0019] This invention enables rapid switching between different celestial body data by independently instantiating and managing a multi-celestial body particle system and combining it with an on-demand display mechanism. During the switching process, a unified state control and camera adjustment strategy ensures that the target celestial body's data is loaded and displayed within a single frame, achieving a near-real-time visual response effect. This mechanism not only supports efficient management of data from multiple celestial bodies in the same scene but also avoids visual interference caused by data overlay, improving the overall interactive experience and system response performance. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0021] Figure 1 This is a flowchart of a method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, according to the present invention.

[0022] Figure 2 This is a schematic diagram of a module of a three-dimensional coordinate adaptive transformation and rendering system for space environment data of multiple celestial bodies according to the present invention. Detailed Implementation

[0023] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0024] This invention provides, for example Figure 1 The method for adaptive 3D coordinate transformation and rendering of space environment data for multiple celestial bodies, as shown, includes the following steps: To achieve adaptive visualization of multi-celestial space environment data within a unified 3D scene, it is first necessary to construct a parameter system that describes the mapping relationship between the physical properties of different celestial bodies and the scene's display attributes. To this end, a celestial body parameter registry is established for unified parameter management of various celestial bodies participating in visualization. In the celestial body parameter registry, each celestial body corresponds to an independent parameter record, which includes at least two core parameters: scene radius. and true radius .

[0025] Among them, scene radius This represents the display scale of the celestial body in a 3D visualization scene. It is a normalized value used to adapt to the visualization needs of celestial bodies of different scales in the same field of view; true radius. The actual physical radius of a celestial body is expressed in kilometers (km), reflecting its scale characteristics in real physical space. By introducing both parameters simultaneously, an effective mapping relationship can be established between rendering space and physical space, thus providing a foundation for subsequent coordinate transformations.

[0026] In a practical implementation, the celestial body parameter registry should contain at least the following typical celestial body parameter configurations: Earth: , ; Moon: , ; Mars: , .

[0027] The above parameters indicate that the scene radius of different celestial bodies is not simply scaled linearly according to their actual radius, but rather subjected to nonlinear compression processing through a specific normalization function. This allows for a unified display of celestial bodies at multiple scales while maintaining visual recognizability. Furthermore, the scene radius... The calculation method uses the following normalization formula: in, The original radius parameter representing a celestial body can usually be understood as a scale parameter that is related to the true radius of the celestial body or comes from the original data; This is a global scaling constant used to control the scale range of the overall scene. In this implementation, the constant... The value is 500.

[0028] This normalization formula employs a square root transformation, its core purpose being to compress the scale differences between different celestial bodies. Because the actual radii of various celestial bodies in the solar system vary greatly—for example, there are significant orders of magnitude differences between the Earth and the Moon, and between Mars—directly using a linear scaling method would make smaller celestial bodies visually difficult to discern, or even invisible. Therefore, by performing a square root operation on the original radius parameters, the scale difference between large-scale and small-scale celestial bodies can be effectively reduced, allowing them to be clearly observed within the same three-dimensional field of view.

[0029] In addition, a global scaling constant is introduced. The goal is to further unify the control of the overall scene, ensuring that the display size of all celestial bodies falls within a range suitable for rendering and interaction. This is achieved through reasonable selection... The value of can strike a balance between visual effects and computational accuracy, ensuring the relative relationship between the sizes of celestial bodies while avoiding rendering anomalies caused by celestial bodies being too large or too small.

[0030] The celestial parameter registry constructed in this way has good scalability and versatility. When it is necessary to support new celestial bodies (such as Venus, Jupiter, or other satellites), only the corresponding parameter record needs to be added to the registry, without modifying the subsequent coordinate transformation logic or rendering process, thus achieving unified processing in multi-celestial body environments. This parameter-driven design effectively solves the problem of strong coupling between coordinate transformation and specific celestial bodies in traditional methods, improving the system's flexibility and maintainability.

[0031] At the same time, due to the scene radius With true radius A clear numerical correspondence has been established, enabling the construction of a consistent proportional mapping mechanism based on the two when performing height mapping of spatial environment data. This avoids inconsistencies between the actual physical height and the visualized height, providing crucial support for achieving high-fidelity spatial environment data display.

[0032] In summary, by establishing a celestial parameter registry that includes both scene radius and real radius, the display scale of celestial bodies is normalized. This ensures the ability to display multiple celestial bodies uniformly while achieving an effective connection between physical space and rendering space, providing fundamental technical support for subsequent 3D coordinate transformation and data rendering.

[0033] To achieve a unified representation of space environment data in multi-celestial 3D scenes, after constructing the celestial parameter registry, coordinate transformation processing of the input space environment data is required. Since the data output by the space environment model is typically given in geographic coordinates, a mapping relationship from the geographic coordinate system to the 3D Cartesian coordinate system must be established. Furthermore, this mapping process must not only be applicable to a single celestial body but also achieve uniform adaptation across different celestial bodies, thereby avoiding the strong coupling between coordinate transformation and specific celestial parameters present in traditional methods.

[0034] Specifically, for each input data point, the data structure can be represented as ( , , , ),in Represents latitude, with a value range of 100. , used to describe the position of the data point in the north-south direction; Represents longitude, with a value range of 100. This is used to describe the distribution of data points in the east-west direction; This indicates the height of the data point relative to the surface of the celestial body, in kilometers (km). This represents the numerical value of the physical quantity corresponding to the data point, such as particle density or ionospheric electron concentration. Before performing the three-dimensional coordinate transformation, the angle units need to be standardized. Since trigonometric function operations are usually based on radians, the input latitude and longitude need to be converted from degrees to radians. The conversion formula is as follows: The above formula converts the original angle data into radians, allowing it to directly participate in subsequent trigonometric function calculations. After the angle conversion, the key is to determine the radial distance of the data point in 3D space, i.e., the distance of the data point relative to the center of the celestial body. Traditional methods typically use the true radius plus height for calculation, but this method is only applicable to single-celestial-body scenes and leads to severe scale inconsistency issues in multi-celestial-body environments. To address this problem, a dual-radius parameter model is introduced, combining the scene radius and the true radius to achieve a unified mapping from physical space to rendering space.

[0035] Specifically, the rendering distance of the data points Calculate using the following formula: in, This represents the normalized display radius of the current celestial body in the 3D scene. This represents the true physical radius of the celestial body. The core idea of ​​this formula is: firstly, through... The height value is converted into a dimensionless proportion relative to the radius of the celestial body, thus eliminating the influence of differences in absolute size between different celestial bodies; this proportion is then multiplied by the scene radius. This process involves calculating the height increment in the rendering space, then adding this increment to the scene radius to obtain the final radial distance of the data point in the 3D scene. This method achieves a consistent mapping between physical height and rendering scale, allowing the same height value to exhibit a physically intuitive relative proportion on different celestial bodies. For example, for smaller celestial bodies (like the Moon), the same height should appear higher visually, while for larger celestial bodies (like the Earth), the same height should appear closer to the surface. This formula is key to achieving this effect. (The text then abruptly shifts to determining the radial distance.) Then, the transformation from spherical coordinates to Cartesian coordinates can be performed, as shown in the following formula: The above formula maps data points from a spherical coordinate system with the celestial center as the origin to a three-dimensional Cartesian coordinate system, where 、 、 These represent the three coordinate components in three-dimensional space. This transformation process follows the standard transformation relationship from spherical coordinates to Cartesian coordinates, and has clear geometric meaning and good numerical stability.

[0036] It is important to emphasize that by introducing scene radius... With true radius The combined use of these methods gives the above coordinate transformation formulas good versatility. Regardless of the type of the target celestial body, it is only necessary to provide the corresponding parameters in the celestial body parameter registry. and The same conversion formula can be directly applied to the parameters without any modification to the algorithm itself, thus achieving a truly unified coordinate transformation across multiple celestial bodies. Further, examples can more intuitively illustrate the effectiveness of this method. When rendering data points at an altitude of 200km on Earth, the height ratio is 200 / 6371 = 0.0314, corresponding to a scene height increment of 0.0314 x 1.259 = 0.00395; while when rendering data points at the same altitude on the Moon, the height ratio is 200 / 1737 = 0.1151, corresponding to a scene height increment of 0.1151 x 0.0234 = 0.00269. It can be seen that although the absolute altitude is the same, due to the different celestial scales, their representation in the scene is significantly different, and this difference precisely reflects the proportional relationships in the real physical world. Therefore, the coordinate transformation method proposed in this invention not only achieves unified processing between different celestial bodies but also ensures the consistency and rationality of the visualization results in a physical sense. Compared to traditional methods, this approach avoids visualization distortion caused by hard-coding celestial radii or ignoring scale mapping relationships, providing a reliable technical means for high-precision three-dimensional representation of space environment data. In summary, this is achieved by introducing the following key formula: This invention achieves adaptive conversion from geographic coordinates to three-dimensional spatial coordinates, and maintains a consistent conversion logic and correct physical proportions in multi-celestial environments, forming the core technical foundation of the entire three-dimensional visualization method.

[0037] In the process of 3D visualization of multi-celestial space environment data, after completing the conversion from geographic coordinates to 3D Cartesian coordinates, it is necessary to further address the issue of data organization and motion consistency within the 3D scene. To this end, a particle system mounting mechanism based on scene layer-level structure is introduced into the 3D scene system to achieve a close association between space environment data and celestial models, thereby ensuring spatial and dynamic consistency of the data in visual representation.

[0038] In a 3D scene, each visualized celestial body corresponds to an independent geometric object, typically existing as a mesh object, used to describe the celestial body's shape and its basic spatial position within the scene. Around this geometric object, an independent particle system instance is created to hold the set of data points generated by the space environment model. These data points have already undergone coordinate transformation in the previous stage to obtain three-dimensional Cartesian coordinates relative to the celestial body's center, thus possessing clear spatial distribution information.

[0039] The particle system does not exist independently in its structure; instead, it is embedded in the scene graph as a child node of the corresponding celestial geometry object. The scene graph is a typical hierarchical structure, characterized by parent-child relationships between nodes, where spatial transformations of higher-level nodes are automatically propagated to lower-level nodes. Utilizing this characteristic, attaching the particle system to the celestial geometry object allows the particle data and the celestial body to form a unified spatial reference system, thus avoiding the problem of frequently calculating the global position of data points in traditional methods.

[0040] Specifically, in this hierarchical structure, celestial geometric objects serve as parent nodes, and their spatial transformations include operations such as translation and rotation. The particle system acts as a child node, with its local coordinate system centered on the celestial body's center. When the parent node undergoes a spatial transformation—for example, the celestial body rotates around its own axis or revolves along its orbit—these transformations are automatically superimposed on the child nodes, ensuring that all data points in the particle system undergo the same spatial changes synchronously. This inheritance mechanism ensures that the data points visually remain attached to the celestial body's surface or its surrounding space, maintaining a consistent motion relationship with the celestial body.

[0041] In terms of specific effects, when a celestial body rotates, its surface and the surrounding space environment data will rotate synchronously. For example, a particle located at a certain latitude and longitude will rotate around the central axis of the celestial body as it rotates, thus maintaining its relative position. This representation conforms to the distribution characteristics of space environment data in the real physical world, making the visualization results more realistic and credible.

[0042] Similarly, when a celestial body revolves along its orbit, the data points in the particle system move as a whole with the celestial body, eliminating the need for individual orbit calculations for each data point. This holistic movement not only reduces computational load but also avoids the accumulation of numerical errors caused by repeated calculations, thereby improving the system's stability and operational efficiency.

[0043] It should be noted that the three-dimensional Cartesian coordinates calculated in the previous stage... The coordinates are local coordinates with the center of the celestial body as the origin, not global coordinates. This is crucial for understanding the entire mechanism. Since the particle system is attached to the celestial node, its local coordinate system is naturally bound to the celestial body. Therefore, there is no need to recalculate the position of the data points in the global coordinate system during each frame of rendering. In other words, the position of the data points always exists relative to the celestial body, and the changes in the position of the celestial body itself are automatically propagated through the scene layer level, thus completing the implicit transformation from local coordinates to global coordinates.

[0044] This design approach brings significant performance advantages. In traditional implementations, if data points exist in the form of global coordinates, the positions of all data points need to be recalculated in each frame based on the current attitude of the celestial body. This results in high computational complexity, which can severely impact rendering efficiency, especially when dealing with large amounts of data. However, by adopting a hierarchical mounting mechanism, coordinate calculations only need to be performed once during the initialization phase, and no repeated calculations are needed during runtime, significantly reducing computational overhead.

[0045] In actual operation, the creation and mounting of particle systems are completed in one go during the scene initialization phase. For each celestial body, a corresponding particle data set is established and managed according to its celestial body classification. After initialization, the particle systems of each celestial body are ready and in a state that can be switched at any time.

[0046] In multi-celestial body visualization scenarios, it's typically unnecessary to display the spatial environment data of all celestial bodies simultaneously. Instead, specific celestial bodies are selected for focused display based on user interaction needs. Therefore, a particle system visibility control mechanism based on rendering targets is introduced during runtime. By setting the currently active celestial body, only the particle system corresponding to that celestial body is made visible, while the particle systems of other celestial bodies remain hidden. This not only reduces the rendering burden but also avoids visual interference caused by the overlay of data from different celestial bodies.

[0047] This visibility control strategy exhibits excellent real-time responsiveness. When a user switches the celestial body of interest, only the visibility attributes of the particle system need to be updated, without rebuilding the data structure or recalculating the coordinates, thus achieving a rapid switching effect. Furthermore, since each particle system is spatially independent, this switching does not introduce additional dependencies, and the system structure remains clear.

[0048] Through this mechanism, the representation of spatial environment data in a 3D scene is no longer an isolated set of points, but rather forms an organic whole with the celestial model. The particle system, as the data carrier, together with celestial geometric objects, constitutes a complete visualization unit, achieving unified management in terms of spatial position, motion behavior, and display control. This design not only improves the system's scalability but also provides a solid foundation for the expansion of subsequent functions, such as multi-layer data overlay and dynamic temporal changes.

[0049] Furthermore, this particle system mounting method exhibits excellent scalability in multi-celestial body environments. When adding a new celestial body, only the corresponding geometric object and particle system need to be created and mounted according to the same hierarchical structure, without modifying the existing logic. The independent yet unified management of each celestial body allows the entire system to flexibly handle complex multi-celestial body visualization needs.

[0050] In summary, by embedding particle systems as child nodes of celestial geometric objects into the scene layer-level structure and utilizing the spatial transformation inheritance relationship between parent and child nodes, automatic synchronization between spatial environment data and celestial motion is achieved. This method avoids redundant calculations, improves rendering efficiency, and ensures physical consistency and visual coherence of data representation, providing an efficient and reliable implementation path for multi-celestial 3D visualization.

[0051] In multi-celestial 3D visualization scenarios, camera parameter settings directly affect the integrity and visibility of the rendering results, among which the near clipping plane parameter... It is one of the key factors determining whether an object can be displayed correctly. In perspective projection models, the distance from the camera is less than... All objects will be clipped and will not participate in the final rendering. Therefore, in scenes where multiple scale celestial bodies coexist, if a fixed [method / approach] is still used... Parameters can cause smaller celestial bodies to fall entirely within the clipping range at certain viewpoints, making them completely invisible. This problem is particularly pronounced in celestial systems containing objects with significantly different scales, such as the Earth and the Moon, severely impacting visualization quality and user experience.

[0052] To address this issue, a dynamic near clipping surface adaptive mechanism based on view distance is introduced. This mechanism allows the near parameter to be dynamically adjusted according to the scale characteristics of the current target celestial body, ensuring that celestial bodies of different scales are rendered correctly when switching viewpoints. The core of this mechanism lies in establishing a correlation between camera parameters and the scene radius of the celestial body, enabling the clipping range to automatically adapt to changes in the scale of the celestial body.

[0053] First, calculate the minimum observation distance based on the display scale of the target celestial body in the scene. This distance is used to describe the distance between the camera and the target celestial body. The minimum reasonable interval is determined to ensure that celestial objects can fully enter the field of view. The calculation method is as follows: in, Indicates the radius of the scene containing the target celestial body. This is the line-of-sight factor, used to control the relative distance between the camera and the celestial body. In this implementation, The value is set to 3.5, meaning the minimum distance between the camera and the center of the celestial body is 3.5 times its scene radius. This proportional relationship ensures that the camera maintains a reasonable observation distance regardless of the size of the celestial body, thus avoiding problems such as the viewpoint being too close or too far.

[0054] To obtain the minimum observation distance Next, the corresponding near clipping plane parameters are calculated. To avoid small celestial bodies being clipped due to excessively large near parameters, and to prevent the depth buffer accuracy from decreasing due to excessively small near parameters, the following calculation method is introduced: in, Represents the near-cut surface coefficient, used to control... The proportional relationship relative to the observation distance is set to 0.1 in this implementation; The minimum threshold is used to limit The lower bound of this value is 0.001. This expression allows for the setting of a value that ensures rendering accuracy while maintaining the desired level of precision. The parameters are adaptively adjusted according to the celestial scale. When the calculation results are small, a minimum threshold is used for constraint to avoid numerical instability or depth conflict issues.

[0055] A key feature of this dynamic adjustment mechanism is that its calculation process relies entirely on the scene radius parameter of the celestial body. This parameter has already been normalized in the preceding processing, thus possessing a unified scale standard. Therefore, regardless of the celestial body being switched to, the appropriate near parameter can be obtained through the same set of calculation logic, achieving consistent processing across celestial bodies.

[0056] In practical applications, it is also necessary to calculate the... Synchronization is applied to multiple camera objects within the rendering system. Typically, a rendering system contains not only cameras for actual drawing but also auxiliary cameras for controlling interactive behavior, such as the virtual cameras used by track controllers. During the rendering loop, these cameras may have state synchronization mechanisms in place; if only one camera is synchronized... If parameters are updated, they may be overwritten by parameters from another camera in the next frame, causing the settings to become invalid. Therefore, it is necessary to update all relevant cameras simultaneously. The parameters are updated, and the projection matrix refresh operation is called after the update to ensure that the new clipping parameters take effect immediately.

[0057] The above mechanism can effectively solve the problem of fixed structures in multi-celestial body scenarios. The problem of small celestial bodies being invisible due to parameters. Taking the Moon as an example, its field radius is approximately: Calculated using the minimum observation distance formula: Further substituting into the near-cutting plane calculation formula: It can be seen that, in a fixed In this case, because the minimum viewing distance is only 0.082, which is less than 0.1, the entire moon is within the clipping range and therefore cannot be rendered. However, after using dynamic adjustment... At that time, the near-cut area is significantly reduced, allowing the moon to fall completely into the visible range and thus be displayed normally.

[0058] This result indicates that by establishing The functional relationship between parameters and celestial scale can effectively avoid rendering anomalies caused by scale differences. Furthermore, this method does not require individual parameter adjustments for different celestial bodies; instead, it achieves automatic adaptation through a unified calculation method, exhibiting good versatility and scalability.

[0059] Further analysis reveals that this mechanism applies not only to smaller celestial bodies like the Moon, but also to celestial bodies of any other scale. When introducing smaller or larger celestial bodies into the scene, as long as their scene radius is calculated correctly, the appropriate radius can be automatically obtained using the above formula. The parameters are adjusted to maintain stable rendering results. This parameter-driven adaptive strategy effectively improves the system's robustness in complex multi-celestial environments. Furthermore, the method has low computational complexity. All parameter calculations are simple multiplication and comparison operations, which can be completed quickly during real-time rendering without significantly impacting system performance. Simultaneously, since parameter updates are only triggered when the viewpoint changes or the target celestial body changes, they do not increase the rendering burden per frame, demonstrating good engineering practicality.

[0060] In a multi-celestial body 3D visualization system, after completing data coordinate transformation, particle system construction, and camera parameter adaptation, a key issue remains: how to perform efficient, stable, and visually coherent switching between different celestial bodies. This process involves not only switching the data display objects but also the coordinated processing of multiple aspects such as camera control, spatial reference frame adjustment, and rendering parameter synchronization. Therefore, a complete multi-celestial body particle system switching mechanism needs to be constructed to achieve seamless transitions between different celestial bodies.

[0061] Upon receiving the rendering target switching command, the first step is to uniformly manage the particle system states of all celestial bodies in the current scene. Since each celestial body has completed its particle system construction during the initialization phase and exists independently, to avoid visual overlap and interference from multiple celestial bodies' data, the particle data sets corresponding to all celestial bodies need to be uniformly set to a hidden state. This process ensures that only the data of the target celestial body is displayed during subsequent switching, thereby guaranteeing the uniqueness of the visual focus and the clarity of data representation.

[0062] After completing the particle system hiding process, the next step is to adjust the spatial assignment of the camera. Since the 3D scene is organized hierarchically, with each celestial body existing as an independent node, the camera needs to establish a spatial association with the currently observed target. Therefore, the camera is removed from the scene node corresponding to the original celestial body and remounted under the scene node of the target celestial body. This operation ensures that the camera's spatial reference frame is consistent with that of the target celestial body, allowing it to automatically inherit the spatial transformations of the target celestial body during subsequent movements. This mounting method avoids the complex calculation problems caused by frequent conversions between different reference coordinate systems and also ensures the stability of the camera's motion.

[0063] After the camera is remounted, the clipping parameters need to be adjusted synchronously to ensure that the target celestial object is fully displayed from the current viewpoint. The specific adjustment process relies on the previously calculated minimum observation distance and near-cropping plane parameters. By recalculating and updating the camera's clipping range, it is made suitable for the scale characteristics of the target celestial object. This step is particularly crucial for small-scale celestial objects, effectively avoiding invisibility issues caused by mismatched clipping parameters.

[0064] Next, distance constraints need to be set in the interactive control to prevent users from entering unreasonable observation ranges during operation. The minimum distance of the orbit controller is limited to the minimum observation distance corresponding to the target celestial body, i.e.: This constraint prevents the camera from getting too close to celestial objects, thus avoiding entering cropped areas or causing visual distortion. At the same time, this distance limit also helps maintain a stable viewing experience, keeping the user always within a reasonable observation range.

[0065] After setting the distance constraints, the camera's initial position needs to be reconfigured so that it can observe the target celestial body from a suitable angle after switching. The camera position is set as follows: This position, located diagonally above the target celestial body, provides both an overall view and a sense of spatial depth. This asymmetrical coordinate setup avoids the camera completely aligning with the celestial body's central axis, resulting in a more three-dimensional observation effect. Furthermore, this position facilitates subsequent user interaction, such as rotation and zoom.

[0066] After the camera position is adjusted, the particle data set corresponding to the target celestial body is finally made visible. Since all particle systems were previously hidden, only the target celestial body's data is reactivated, thus achieving the switching process from displaying no data to displaying the target data. This operation has a clear state transition logic, ensuring the controllability and consistency of the switching process.

[0067] The aforementioned series of operations are strictly dependent in their execution order, with each step interconnected to form a complete switching process. From hiding the particle system to remounting the camera, updating cropping parameters, setting distance constraints, and adjusting the viewing angle, each step is indispensable for ultimately displaying the target data. This orderly processing method avoids problems such as flickering, misalignment, or data overlay during the switching process.

[0068] In actual operation, these operations are typically completed within a single frame, meaning all state updates are completed within one rendering cycle. Because modern graphics rendering systems usually have high frame rates and extremely short frame times, users visually perceive almost no intermediate process; instead, it appears as an instantaneous viewpoint transition. This instantaneous switching effect is crucial for enhancing the user experience.

[0069] Furthermore, this switching mechanism boasts excellent scalability. When more celestial bodies or more types of data need to be supported, smooth expansion can be achieved simply by adding the corresponding particle systems and node relationships during the initialization phase and uniformly managing their visibility and camera mounting relationships within the switching logic. The entire process requires no modification to the core algorithm, demonstrating high system flexibility.

[0070] Overall, this multi-celestial particle system switching method not only solves the problem of data display between different celestial bodies, but also achieves coordinated unity between camera control, spatial hierarchy structure, and rendering parameters. Through reasonable sequence control and parameter update strategies, the stability and efficiency of the switching process are ensured, while also providing reliable support for the dynamic display of complex space environment data.

[0071] In summary, by sequentially performing operations such as hiding the particle system, adjusting the camera mount, updating the clipping parameters, setting distance constraints, resetting the camera position, and displaying the target particle system, and combining the following key relationships: It enables rapid switching of spatial data display objects and viewpoint repositioning in multi-celestial environments, significantly improving the system's interactive responsiveness and overall performance while ensuring the continuity of rendering effects.

[0072] To illustrate the specific implementation process of this method, a 3D visualization of space environment particle density data is selected as the application scenario. Atomic oxygen density, electron density, and carbon dioxide density data are displayed on three celestial bodies: Earth, the Moon, and Mars. The 3D scene is built based on WebGL and implemented using the Three.js engine, and includes the major celestial bodies of the solar system.

[0073] I. Celestial Parameter Configuration A registry of celestial body parameters is established to uniformly manage the scale parameters of different celestial bodies. The parameters of each celestial body are as follows: Table 1: Parameters of various celestial bodies; II. Coordinate Transformation: Taking Earth's atomic oxygen data as an example, the data points are: Angle conversion: Radial distance calculation: Spatial coordinate calculation: This point is located in the direction of the Earth's South Pole, at a distance of [distance from the center]. Each scene unit. Taking the moon as an example, data points at the same altitude: It is evident that the mapping ratio of the same altitude differs on different celestial bodies: Earth's is approximately... The moon is approximately This reflects the actual physical proportions.

[0074] III. Particle System Loading During the scene initialization phase, a particle system is created for each celestial body and attached as a child node to the corresponding celestial body Mesh object, for example: mesh.add(particleSystem.getGroup()) Achieve the following effect by using the scene layer hierarchy: The rotation of celestial bodies (around the Y-axis) is automatically transmitted to the particle system; The revolution of celestial bodies is automatically transmitted to the particle system; Particle coordinates are based on local coordinates, eliminating the need to update the global position every frame.

[0075] IV. Near-clipping plane adaptation: When the celestial body switches to the Moon, the following calculations are performed: Synchronize the parameter settings to: Render camera: camera.near; Virtual camera: fakeCamera.near and call: updateProjectionMatrix(). The moon was not visible when the original parameter near=0.1 (because 0.0819<0.1), but it can be displayed normally after adjustment to near=0.00819.

[0076] V. Examples of Multi-Celestial Body Switching When received: renderTarget="Moon"; Perform the following procedure: 1. Hide all particle systems; 2. The camera is mounted on the lunar node. 3. Set near=0.00819; 4. Set the minimum distance to 0.0819; 5. Set the camera position: (0.0819, 0.0273, 0); 6. Display the lunar particle system.

[0077] The entire process is completed in about 16ms (1 frame), achieving an instant switching effect.

[0078] This invention proposes an adaptive coordinate transformation method with dual radius parameters, decoupling and co-modeling the scene radius and the real radius, achieving unified mapping of different celestial spatial data within the same transformation formula framework. This method avoids the hard-coded dependence on a single celestial radius parameter found in traditional techniques, giving the coordinate transformation logic good versatility and scalability. When introducing new celestial objects, only registration in the parameter system is required, without modifying the core algorithm, thus significantly reducing system maintenance costs and improving adaptability. It effectively solves the problem of strong coupling between coordinate transformation and specific celestial objects in existing technologies.

[0079] This invention, based on a scene graph parent-child hierarchical structure, establishes a subordinate relationship between particle data and corresponding celestial body nodes, enabling spatial data to automatically inherit the spatial transformation attributes of celestial bodies. Under this mechanism, the rotation and revolution behaviors of celestial bodies can be directly transmitted to the particle system without requiring frame-by-frame position updates for each data point, thus avoiding the performance overhead caused by redundant calculations. This hierarchical transmission-based processing method not only improves system operating efficiency but also enhances the spatial consistency between data and celestial bodies, making the visualization results more consistent with the laws of real physical motion.

[0080] This invention constructs a dynamic near-clipping plane adaptive algorithm based on view distance. By introducing parameter relationships related to celestial scale, it achieves real-time adjustment of near-clipping plane parameters. Furthermore, by combining this with a dual-camera synchronization strategy, it ensures that parameters remain consistent across different cameras during rendering, avoiding display anomalies caused by state overlap. This method effectively solves the problem of small celestial bodies failing to display in multi-scale scenes due to improper clipping plane settings, improving system stability and adaptability while maintaining rendering accuracy.

[0081] This invention enables rapid switching between different celestial body data by independently instantiating and managing a multi-celestial body particle system and combining it with an on-demand display mechanism. During the switching process, a unified state control and camera adjustment strategy ensures that the target celestial body's data is loaded and displayed within a single frame, achieving a near-real-time visual response effect. This mechanism not only supports efficient management of data from multiple celestial bodies in the same scene but also avoids visual interference caused by data overlay, improving the overall interactive experience and system response performance.

[0082] This invention provides, for example Figure 2 The system shown is a 3D coordinate adaptive transformation and rendering system for multi-celestial body space environment data, including a celestial body parameter registration module, a coordinate transformation module, a scene graph management module, a camera adaptation module, and a rendering target switching module. The celestial body parameter registration module stores and manages the scene radius and actual radius of each celestial body, and provides parameter query based on celestial body identifiers; The coordinate transformation module receives the geographic coordinates of the data points and the target celestial body identifier, obtains the corresponding scene radius and real radius from the celestial body parameter registration module based on the celestial body identifier, and performs transformation processing on the geographic coordinates to obtain the corresponding three-dimensional Cartesian coordinates. The scene graph management module creates corresponding particle data sets for each celestial body, attaches the particle data sets to the scene nodes of the corresponding celestial body, and manages the display status of the particle data sets corresponding to each celestial body. The camera adaptive module calculates the minimum observation distance based on the scene radius of the target celestial body during the target celestial body switching process, and calculates the near clipping surface parameters based on the minimum observation distance, updates the camera's near clipping surface parameters, and adjusts the camera position and interactive control constraints at the same time. The rendering target switching module receives the target celestial body identifier, controls the display state of the particle data set corresponding to each celestial body based on the target celestial body identifier, adjusts the spatial relationship between the camera and the target celestial body, and coordinates the camera adaptive module to complete the parameter update.

[0083] The present invention provides a method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies. This method is implemented through the aforementioned system for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies. For details of the specific method and process of the system for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, please refer to the embodiment of the above-mentioned method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, which will not be repeated here.

[0084] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for adaptive 3D coordinate transformation and rendering of space environment data for multiple celestial bodies, characterized in that, Includes the following steps: Construct a celestial parameter registry to record the configuration parameters for each celestial body to be visualized. Each parameter record includes the scene radius and the actual radius. The latitude, longitude, and altitude of the input data points above the celestial body's surface are obtained. Based on the scene radius and real radius of the target celestial body, the altitude is normalized and mapped to the scene space to obtain the corresponding rendering distance. The three-dimensional Cartesian coordinates of the data points are then calculated based on the rendering distance. A corresponding particle data set is established for each celestial body, and the particle data set is mounted to the scene node of the corresponding celestial body according to three-dimensional Cartesian coordinates, so that the particle data set changes synchronously with the spatial transformation of the corresponding celestial body. When switching the viewpoint of the target celestial body, the minimum observation distance is calculated based on the scene radius of the target celestial body, and the near clipping surface parameters are adaptively calculated based on the minimum observation distance, while the near clipping surface parameters of the camera are updated. In response to the target celestial body switching command, the camera parameters are adjusted based on the updated near clipping plane parameters, and the camera viewpoint is associated with the scene node of the target celestial body. At the same time, the visibility state of the particle data set corresponding to different celestial bodies is switched to complete the rendering switching of multi-celestial body data.

2. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 1, characterized in that, In a multi-celestial 3D scene, to unify the display parameters of celestial bodies of different scales, the display radius of the celestial bodies is normalized. The steps are as follows: The original radius parameters of the celestial body to be processed are read, and these original radius parameters are used as inputs in subsequent calculations. The original radius parameter is square-rooted to perform nonlinear compression on the original scale. The square root result is proportionally calculated with a preset global scaling constant to obtain the corresponding scene radius value; The obtained scene radius is written into the parameter set as the celestial display scale parameter for subsequent coordinate transformation and rendering processes.

3. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 2, characterized in that, The ratio between the square root operation and the global scaling constant is fixed in advance and kept consistent. The scene radius is stored in a structured form in the parameter set and the calculation rules are kept consistent when calling different celestial bodies.

4. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 2, characterized in that, In the process of mapping space environment data, in order to establish the correspondence between altitude values ​​and celestial scales, the altitude of the data points is proportionally converted. The steps are as follows: Obtain the height value of the data point and the true radius parameter of the corresponding celestial body, and use both as calculation inputs; The height value is compared with the actual radius parameter to obtain the corresponding dimensionless ratio value; The height increment in the scene space is obtained by numerically mapping the scale value to the scene radius. The height increment is superimposed on the scene radius to form the radial distance parameter of the data point in the scene, which is then used in the 3D coordinate calculation.

5. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 4, characterized in that, The mapping between altitude and scene radius is calculated by using square root transformation to increase the scene increment, and the scale is adjusted by a global scaling constant to ensure that the altitude mapping of each celestial body is consistent, forming a unified radial distance parameter input for 3D coordinate calculation.

6. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 4, characterized in that, Under the condition of switching between multiple celestial perspectives, the near-clipping plane parameters are dynamically calculated. The steps are as follows: Obtain the corresponding scale parameters based on the scene radius of the target celestial body, and determine the minimum observation distance accordingly; The minimum observation distance is multiplied by a preset scaling factor to obtain candidate values ​​for the near cutting plane. The candidate values ​​are compared with a preset minimum threshold, and the maximum value is selected as the near-cutting plane parameter. The calculated near clipping plane parameters are written into the parameter sets of the rendering camera and the control camera, respectively, and the projection parameter update operation is triggered.

7. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 6, characterized in that, When calculating near clipping plane parameters, the preset scaling factor and minimum threshold are adjusted via configurable parameters, and the update operation is applied to all rendering camera and control camera instances.

8. The method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies according to claim 6, characterized in that, In the process of displaying multi-celestial data and switching perspectives, relevant parameters are configured to coordinate camera position and interactive control constraints. The steps are as follows: The minimum observation distance is obtained based on the scale parameters of the target celestial body, and this distance is used as a constraint reference value; The distance parameter in the interactive control is set, and its minimum value is limited to the minimum observation distance; The camera's three-dimensional position is assigned values ​​according to a preset spatial ratio to determine the viewing angle; After adjusting the camera position, the display state of the particle data set is switched, and the currently displayed object is updated.

9. A method for adaptive transformation and rendering of three-dimensional coordinates of space environment data for multiple celestial bodies, as described in claim 8, is characterized in that... During the display of multi-celestial data and the switching of perspectives, the adjustment of camera position is further restricted. The camera is required to be mounted on the target celestial node and the minimum distance parameter of the orbit controller is updated synchronously. At the same time, the three-dimensional position of the camera is adjusted to form an oblique upward observation perspective. The visibility of the particle data set is updated according to the state of the target celestial body.

10. A three-dimensional coordinate adaptive transformation and rendering system for multi-celestial body space environment data, used to implement the three-dimensional coordinate adaptive transformation and rendering method for multi-celestial body space environment data as described in any one of claims 1-9, characterized in that, This includes a celestial parameter registration module, a coordinate transformation module, a scene graph management module, a camera adaptation module, and a rendering target switching module. The celestial body parameter registration module stores and manages the scene radius and actual radius of each celestial body, and provides parameter query based on celestial body identifiers; The coordinate transformation module receives the geographic coordinates of the data points and the target celestial body identifier, obtains the corresponding scene radius and real radius from the celestial body parameter registration module based on the celestial body identifier, and performs transformation processing on the geographic coordinates to obtain the corresponding three-dimensional Cartesian coordinates. The scene graph management module creates corresponding particle data sets for each celestial body, attaches the particle data sets to the scene nodes of the corresponding celestial body, and manages the display status of the particle data sets corresponding to each celestial body. The camera adaptive module calculates the minimum observation distance based on the scene radius of the target celestial body during the target celestial body switching process, and calculates the near clipping surface parameters based on the minimum observation distance, updates the camera's near clipping surface parameters, and adjusts the camera position and interactive control constraints at the same time. The rendering target switching module receives the target celestial body identifier, controls the display state of the particle data set corresponding to each celestial body based on the target celestial body identifier, adjusts the spatial relationship between the camera and the target celestial body, and coordinates the camera adaptive module to complete the parameter update.

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