Quick conversion method for SVG and geographic coordinates

Abstract

The invention discloses an SVG and geographic coordinate rapid conversion method. The method comprises the following steps: acquiring a standardized dynamic intermediate coordinate system parameter; using the updated affine transformation matrix to convert points of the dynamic intermediate coordinate system to obtain a dynamic projection conversion result of the SVG coordinate system; obtaining quadtree tile data; performing local correction on the dynamic projection conversion result of the SVG coordinate system to obtain a corrected dynamic projection conversion result of the SVG coordinate system; and rendering the corrected dynamic projection conversion result of the SVG coordinate system into an interactive SVG graph in real time through a video memory management strategy. According to the method, efficient conversion between the geographic coordinates and the SVG coordinates is achieved, the calculation efficiency and the dynamic interaction capability are remarkably improved, the conversion precision in a complex scene is ensured, meanwhile, system resource occupation is reduced, and a light-weight and high-response solution is provided for Web maps, mobile terminal GIS and tourism digital twinning application with the high real-time requirement.

Description

Technical Field

[0001] The present invention relates to the fields of geographic information systems and computer graphics, and in particular to a method for fast conversion between SVG (scalable vector graphics) and geographic coordinates. Background Art

[0002] Existing SVG and geographic coordinate conversion technologies have the following flaws:

[0003] (1) Traditional CPU single-threaded algorithms take more than 10 seconds to process millions of data points and cannot support real-time interactions (such as map dragging and zooming), which leads to efficiency bottlenecks.

[0004] (2) The error of linear affine transformation exceeds 3 pixels under complex projections (such as Spherical Mercator), and the error is further amplified in high curvature areas (such as the Qinghai-Tibet Plateau), resulting in insufficient accuracy.

[0005] (3) Pre-computation of the full data requires several GB of memory, making it difficult to deploy on mobile devices;

[0006] The above defects are particularly prominent in tourism digital twin scenarios, resulting in problems such as low conversion accuracy in complex scenarios, high interaction delay, and limited mobile performance. Summary of the Invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides a method for fast conversion between SVG and geographic coordinates.

[0008] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0009] A method for quickly converting SVG to geographic coordinates includes the following steps:

[0010] Obtaining original geographic data, constructing a dynamic intermediate coordinate system based on the original geographic data, and calculating the scaling ratio and offset of the dynamic intermediate coordinate system in real time to obtain standardized dynamic intermediate coordinate system parameters;

[0011] Obtain the user's real-time interaction instructions, build a real-time updated affine transformation matrix based on the standardized dynamic intermediate coordinate system parameters and the user's real-time interaction instructions, and use the GPU parallel computing to transform the points of the dynamic intermediate coordinate system using the updated affine transformation matrix to obtain the dynamic projection transformation results of the SVG coordinate system;

[0012] The original geographic data is layered to obtain geographic data at different levels. The zoom level is determined based on the user's real-time interactive instructions. The geographic data of the corresponding level is dynamically loaded and rendered according to the zoom level. The R-tree index is used to quickly locate geographic features in the loaded and rendered geographic data to obtain quadtree tile data.

[0013] Based on the quadtree tile data, the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management and adaptive selection of the interpolation algorithm to obtain the corrected dynamic projection transformation result of the SVG coordinate system;

[0014] Through GPU parallel acceleration and dynamic frame rate control, the dynamic projection transformation results of the corrected SVG coordinate system are rendered into interactive SVG graphics in real time.

[0015] Furthermore, the normalized dynamic intermediate coordinate system parameters are calculated and expressed as:

[0016]

[0017] offset x =x min ,

[0018] offset y =y min

[0019] Among them: lonscale is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, offset x To standardize the offset of the dynamic intermediate coordinate system parameters on the x-axis, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters, x max is the maximum value of the horizontal coordinate in the dynamic intermediate coordinate system, x min is the minimum value of the horizontal coordinate in the dynamic intermediate coordinate system, lon max is the maximum longitude in the dynamic intermediate coordinate system, lon min is the maximum longitude in the dynamic intermediate coordinate system, y max is the maximum value of the ordinate in the dynamic intermediate coordinate system, y min is the minimum value of the ordinate in the dynamic intermediate coordinate system, lat max is the maximum latitude in the dynamic intermediate coordinate system, lat min It is the maximum latitude in the dynamic intermediate coordinate system.

[0020] Furthermore, the real-time updated affine transformation matrix is ​​expressed as:

[0021]

[0022] Where: A is the real-time updated affine transformation matrix, k is the scaling factor in the user's real-time interaction instruction, θ is the rotation angle in the user's real-time interaction instruction, lonscale is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, d x The offset on the x-axis in the user's real-time interactive instructions, offset x is the offset on the x-axis in the normalized dynamic intermediate coordinate system parameters, d y The offset on the y-axis in the user's real-time interactive instructions, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters.

[0023] Furthermore, the updated affine transformation matrix is ​​used to transform the points of the dynamic intermediate coordinate system to obtain the dynamic projection transformation result of the SVG coordinate system, including the following steps:

[0024] Expand the points of the dynamic intermediate coordinate system into homogeneous coordinates;

[0025] Multiply the updated affine transformation matrix and the homogeneous coordinates by matrix multiplication to obtain the three-dimensional transformed coordinates;

[0026] Take the first two dimensions of the three-dimensional transformed coordinates to obtain the dynamic projection transformation result of the SVG coordinate system.

[0027] Furthermore, based on the quadtree tile data, through dynamic control point management and adaptive selection of the interpolation algorithm, the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain the corrected dynamic projection transformation result of the SVG coordinate system. The specific process is: based on the quadtree tile data, the regional feature identifier is determined, the regional feature identifier includes a flat area feature identifier and a complex terrain area feature identifier, the flat area feature identifier is set to adaptively select bilinear interpolation, the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain the corrected dynamic projection transformation result of the SVG coordinate system, and the complex terrain area feature identifier is set to adaptively select thin plate spline interpolation, and the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management to obtain the corrected dynamic projection transformation result of the SVG coordinate system.

[0028] Furthermore, the flat area feature identifier is set to adaptively select bilinear interpolation, and the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain the corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as:

[0029] x svg =a0+a1x′+a2y′+a3x′y′

[0030] Where: x svg is the corrected SVG coordinate, a0, a1, a2, and a3 are all bilinear interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

[0031] Furthermore, the thin plate spline interpolation is adaptively selected based on the feature identification of the complex terrain area, and the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management to obtain the corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as:

[0032]

[0033] Where: x svg is the corrected SVG coordinate, w i is the weight coefficient, φ(r)=r 2 lnr,(x i ,y i ) is the i-th control point, i is the index of the control point, n is the number of control points, c0, c1, c2, and c3 are all thin plate spline interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

[0034] The present invention has the following beneficial effects:

[0035] (1) The present invention can simplify computational complexity and support real-time view change response by constructing a dynamic intermediate coordinate system and unifying the coordinate reference;

[0036] (2) The present invention obtains geographic data of different levels by stratifying the original geographic data, determines the zoom level based on the user's real-time interactive instructions, dynamically loads and renders the geographic data of the corresponding level according to the zoom level, and uses R-tree index to quickly locate geographic elements in the loaded and rendered geographic data, thereby optimizing data loading and query efficiency and reducing redundant calculations and memory usage.

[0037] (3) The present invention uses GPU parallel acceleration in the two processes of transforming points in the dynamic intermediate coordinate system using an updated affine transformation matrix and rendering the dynamic projection transformation results of the corrected SVG coordinate system into interactive SVG graphics in real time. This can leverage hardware parallel capabilities to accelerate large-scale coordinate transformations, thereby ensuring a smooth interactive experience.

[0038] (4) The present invention performs local correction on the dynamic projection transformation result of the SVG coordinate system through dynamic control point management and adaptive selection of interpolation algorithm to obtain the corrected dynamic projection transformation result of the SVG coordinate system, thereby realizing adaptive curvature compensation and solving the problem of accuracy deviation under complex terrain. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The figure is a flowchart of a method for quickly converting SVG to geographic coordinates. DETAILED DESCRIPTION

[0040] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0041] like Figure 1 As shown, a method for quickly converting SVG to geographic coordinates includes steps S1-S5, which are specifically as follows:

[0042] S1. Obtain original geographic data, construct a dynamic intermediate coordinate system based on the original geographic data, and calculate the scaling ratio and offset of the dynamic intermediate coordinate system in real time to obtain standardized dynamic intermediate coordinate system parameters.

[0043] In an optional embodiment of the present invention, this step is the reference layer of the entire coordinate transformation process. The present invention constructs a dynamic intermediate coordinate system and calculates the scaling ratio and offset of the dynamic intermediate coordinate system in real time to obtain standardized dynamic intermediate coordinate system parameters, thereby providing standardized input for subsequent processes.

[0044] Specifically, the present invention constructs a dynamic intermediate coordinate system based on the original geographic data. This dynamic intermediate coordinate system adopts a Cartesian coordinate system, locating spatial points via mutually perpendicular x- and y-axes to simplify subsequent linear transformation calculations. The origin of the dynamic intermediate coordinate system is set to the center of the map (e.g., the intersection of the equator and prime meridian for global maps, or the geometric center for local maps), and the range of the dynamic intermediate coordinate system is determined based on the original geographic data.

[0045] The standardized dynamic intermediate coordinate system parameters include the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, the offset on the x-axis in the standardized dynamic intermediate coordinate system parameters, and the offset on the y-axis in the standardized dynamic intermediate coordinate system parameters.

[0046] The present invention calculates the standardized dynamic intermediate coordinate system parameters, which are expressed as:

[0047]

[0048]

[0049] offset x =xmin ,

[0050] offset y =y min

[0051] Among them: lonscale is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, offset x To standardize the offset of the dynamic intermediate coordinate system parameters on the x-axis, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters, x max is the maximum value of the horizontal coordinate in the dynamic intermediate coordinate system, x min is the minimum value of the horizontal coordinate in the dynamic intermediate coordinate system, lon max is the maximum longitude in the dynamic intermediate coordinate system, lon min is the maximum longitude in the dynamic intermediate coordinate system, y max is the maximum value of the ordinate in the dynamic intermediate coordinate system, y min is the minimum value of the ordinate in the dynamic intermediate coordinate system, lat max is the maximum latitude in the dynamic intermediate coordinate system, lat min It is the maximum latitude in the dynamic intermediate coordinate system.

[0052] The present invention adopts a dynamic update mechanism, specifically: when the user zooms or drags the map, the present invention reconstructs the dynamic intermediate coordinate system and calculates the zoom ratio and offset of the dynamic intermediate coordinate system in real time.

[0053] S2. Obtain the user's real-time interaction instructions, build a real-time updated affine transformation matrix based on the standardized dynamic intermediate coordinate system parameters and the user's real-time interaction instructions, and use the GPU parallel operation to transform the points of the dynamic intermediate coordinate system using the updated affine transformation matrix to obtain the dynamic projection transformation result of the SVG coordinate system.

[0054] In an optional embodiment of the present invention, the present invention obtains a user's real-time interaction instruction, which includes a zoom factor, a rotation angle, an offset on the x-axis, and an offset on the y-axis.

[0055] The present invention constructs a real-time updated affine transformation matrix based on the standardized dynamic intermediate coordinate system parameters and the user's real-time interactive instructions, which is expressed as:

[0056]

[0057] Where: A is the real-time updated affine transformation matrix, k is the scaling factor in the user's real-time interaction instruction, θ is the rotation angle in the user's real-time interaction instruction, lonscale is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, d x The offset on the x-axis in the user's real-time interactive instructions, offset x is the offset on the x-axis in the normalized dynamic intermediate coordinate system parameters, d y The offset on the y-axis in the user's real-time interactive instructions, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters.

[0058] The present invention uses an updated affine transformation matrix to transform the points of the dynamic intermediate coordinate system to obtain a dynamic projection transformation result of the SVG coordinate system, including the following steps:

[0059] A1. Expand the points of the dynamic intermediate coordinate system into homogeneous coordinates.

[0060] A2. Multiply the updated affine transformation matrix and the homogeneous coordinates by matrix multiplication to obtain three-dimensional transformed coordinates.

[0061] A3. Take the first two dimensions of the three-dimensional transformed coordinates to obtain the dynamic projection transformation result of the SVG coordinate system.

[0062] Specifically, the present invention dynamically maps the intermediate coordinate system defined in step 1 to the target SVG coordinate system through an affine transformation matrix, thereby realizing real-time scaling, rotation, and translation operations of the map.

[0063] Specifically, the present invention is based on GPU parallel computing and uses an updated affine transformation matrix to transform the points of the dynamic intermediate coordinate system to obtain the dynamic projection transformation results of the SVG coordinate system. Specifically, the updated affine transformation matrix A and the points of the dynamic intermediate coordinate system are batch transferred to the GPU, and parallel computing is performed through the WebGL vertex shader to obtain the dynamic projection transformation results of the SVG coordinate system.

[0064] S3. Layer the original geographic data to obtain geographic data at different levels, determine the zoom level based on the user's real-time interactive instructions, dynamically load and render the geographic data of the corresponding level according to the zoom level, and use the R-tree index to quickly locate the geographic features in the loaded and rendered geographic data to obtain quadtree tile data.

[0065] In an optional embodiment of the present invention, the present invention performs data stratification on the original geographic data to obtain geographic data of different levels. The specific process is as follows: the original geographic data is recursively divided into tiles, each tile is associated with a level, a minimum enclosing rectangle is established for the geographic elements in each tile, and a tree-like query structure is formed. The zoom level is determined based on the user's real-time interactive instructions, and the level is selected according to the zoom level. For example, when the user zooms to level 5, all associated level 5 tile data is loaded, and then the R-tree is used to quickly locate the geographic elements in the loaded and rendered geographic data to obtain quadtree tile data.

[0066] S4. Based on the quadtree tile data, the dynamic control point management and the adaptive selection of the interpolation algorithm are used to locally correct the dynamic projection transformation result of the SVG coordinate system to obtain a corrected dynamic projection transformation result of the SVG coordinate system.

[0067] In an optional embodiment of the present invention, the present invention is based on quadtree tile data, through dynamic control point management and interpolation algorithm adaptive selection, to locally correct the dynamic projection transformation result of the SVG coordinate system to obtain a corrected dynamic projection transformation result of the SVG coordinate system. The specific process is: based on the quadtree tile data, the regional feature identifier is determined, the regional feature identifier includes a flat area feature identifier and a complex terrain area feature identifier, the flat area feature identifier is set to adaptively select bilinear interpolation, the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain a corrected dynamic projection transformation result of the SVG coordinate system, and the complex terrain area feature identifier is set to adaptively select thin plate spline interpolation, and the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management to obtain a corrected dynamic projection transformation result of the SVG coordinate system.

[0068] The present invention sets a flat area feature identifier to adaptively select bilinear interpolation, and locally corrects the dynamic projection transformation result of the SVG coordinate system to obtain a corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as:

[0069] x svg =a0+a1x′+a2y′+a3x′y′

[0070] Where: x svg is the corrected SVG coordinate, a0, a1, a2, and a3 are all bilinear interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

[0071] The present invention sets a complex terrain area feature identifier to adaptively select thin plate spline interpolation, and performs local correction on the dynamic projection transformation result of the SVG coordinate system through dynamic control point management to obtain a corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as:

[0072]

[0073] Where: x svg is the corrected SVG coordinate, w i is the weight coefficient, φ(r)=r 2 lnr,(x i ,y i ) is the i-th control point, i is the index of the control point, n is the number of control points, c0, c1, c2, and c3 are all thin plate spline interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

[0074] The control points in the present invention represent key reference points predefined in geographic space (original coordinates) and SVG graphic space (target coordinates) and are used to calibrate the accuracy of coordinate conversion.

[0075] S5. Through GPU parallel acceleration and dynamic frame rate control, the dynamic projection transformation results of the corrected SVG coordinate system are rendered into interactive SVG graphics in real time.

[0076] In an optional embodiment of the present invention, the present invention uses GPU parallel acceleration and dynamic frame rate control to render the dynamic projection conversion results of the corrected SVG coordinate system into interactive SVG graphics in real time through a video memory management strategy. The specific process is: the dynamic projection conversion results of the corrected SVG coordinate system are transferred to the GPU video memory in batches, and the corresponding target frame rates of zoom / pan, stillness and no operation in the user operation status are set to 60fps, 30fps and 10fps respectively through dynamic frame rate control, and the corresponding rendering priorities are real-time response, balanced performance and energy-saving mode respectively, and then the target frame rate and the corresponding rendering priority are dynamically adjusted according to the user operation status to render the dynamic projection conversion results of the corrected SVG coordinate system into interactive SVG graphics in real time.

[0077] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0078] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0079] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0080] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

[0081] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific descriptions and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical teachings disclosed in the present invention without departing from the essence of the present invention, and such variations and combinations are still within the scope of protection of the present invention.

Claims

1. A method for fast conversion between SVG and geographic coordinates, characterized in that: The following steps are involved: Obtaining original geographic data, constructing a dynamic intermediate coordinate system based on the original geographic data, and calculating the scaling ratio and offset of the dynamic intermediate coordinate system in real time to obtain standardized dynamic intermediate coordinate system parameters; Obtain the user's real-time interaction instructions, build a real-time updated affine transformation matrix based on the standardized dynamic intermediate coordinate system parameters and the user's real-time interaction instructions, and use the GPU parallel computing to transform the points of the dynamic intermediate coordinate system using the updated affine transformation matrix to obtain the dynamic projection transformation results of the SVG coordinate system; The original geographic data is layered to obtain geographic data at different levels. The zoom level is determined based on the user's real-time interactive instructions. The geographic data of the corresponding level is dynamically loaded and rendered according to the zoom level. The R-tree index is used to quickly locate geographic features in the loaded and rendered geographic data to obtain quadtree tile data. Based on the quadtree tile data, the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management and adaptive selection of the interpolation algorithm to obtain the corrected dynamic projection transformation result of the SVG coordinate system; Through GPU parallel acceleration and dynamic frame rate control, the dynamic projection transformation results of the corrected SVG coordinate system are rendered into interactive SVG graphics in real time.

2. The method for rapid conversion between SVG and geographic coordinates according to claim 1, wherein: Calculate the normalized dynamic intermediate coordinate system parameters, expressed as: offset x =x min , offset y =y min Among them: lonscale is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, offset x To standardize the offset of the dynamic intermediate coordinate system parameters on the x-axis, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters, x max is the maximum value of the horizontal coordinate in the dynamic intermediate coordinate system, x min is the minimum value of the horizontal coordinate in the dynamic intermediate coordinate system, lon max is the maximum longitude in the dynamic intermediate coordinate system, lon min is the maximum longitude in the dynamic intermediate coordinate system, y max is the maximum value of the ordinate in the dynamic intermediate coordinate system, y min is the minimum value of the ordinate in the dynamic intermediate coordinate system, lat max is the maximum latitude in the dynamic intermediate coordinate system, lat min It is the maximum latitude in the dynamic intermediate coordinate system.

3. The method for rapid conversion between SVG and geographic coordinates according to claim 1, wherein: The affine transformation matrix updated in real time is expressed as: Where: A is the real-time updated affine transformation matrix, k is the scaling factor in the user's real-time interaction instructions, θ is the rotation angle in the user's real-time interaction instructions, lonscal e is the longitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, latscale is the latitude scaling ratio in the standardized dynamic intermediate coordinate system parameters, d x The offset on the x-axis in the user's real-time interactive instructions, offset x is the offset on the x-axis in the normalized dynamic intermediate coordinate system parameters, d y The offset on the y-axis in the user's real-time interactive instructions, offset y The offset on the y-axis in the normalized dynamic intermediate coordinate system parameters.

4. The method for rapid conversion between SVG and geographic coordinates according to claim 1, wherein: The updated affine transformation matrix is ​​used to transform the points in the dynamic intermediate coordinate system to obtain the dynamic projection transformation result of the SVG coordinate system, including the following steps: Expand the points of the dynamic intermediate coordinate system into homogeneous coordinates; Multiply the updated affine transformation matrix and the homogeneous coordinates by matrix multiplication to obtain the three-dimensional transformed coordinates; Take the first two dimensions of the three-dimensional transformed coordinates to obtain the dynamic projection transformation result of the SVG coordinate system.

5. The method for rapid conversion between SVG and geographic coordinates according to claim 1, wherein: Based on the quadtree tile data, through dynamic control point management and adaptive selection of interpolation algorithm, the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain the corrected dynamic projection transformation result of the SVG coordinate system. The specific process is: based on the quadtree tile data, the regional feature identifier is determined, the regional feature identifier includes a flat area feature identifier and a complex terrain area feature identifier, the flat area feature identifier is set to adaptively select bilinear interpolation, the dynamic projection transformation result of the SVG coordinate system is locally corrected to obtain the corrected dynamic projection transformation result of the SVG coordinate system, and the complex terrain area feature identifier is set to adaptively select thin plate spline interpolation, and the dynamic projection transformation result of the SVG coordinate system is locally corrected through dynamic control point management to obtain the corrected dynamic projection transformation result of the SVG coordinate system.

6. The method for rapid conversion between SVG and geographic coordinates according to claim 5, wherein: Set the flat area feature identifier to adaptively select bilinear interpolation, and perform local correction on the dynamic projection transformation result of the SVG coordinate system to obtain the corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as: x sυg =a0+a1x′+a2y′+α3x′y′ Where: x svg is the corrected SVG coordinate, a0, a1, a2, and a3 are all bilinear interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

7. The method for rapid conversion between SVG and geographic coordinates according to claim 5, wherein: Set the complex terrain area feature identifier to adaptively select thin plate spline interpolation, and perform local correction on the dynamic projection transformation result of the SVG coordinate system through dynamic control point management to obtain the corrected dynamic projection transformation result of the SVG coordinate system, which is expressed as: Where: x svg is the corrected SVG coordinate, w i is the weight coefficient, φ(r)=r 2 ln r,(x i ,y i ) is the i-th control point, i is the index of the control point, n is the number of control points, c0, c1, c2, and c3 are all thin plate spline interpolation coefficients, x′ is the x-axis coordinate of the SVG coordinate system, and y′ is the y-axis coordinate of the SVG coordinate system.

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