Method and device for obtaining stereoscopic images of three-level land classification spots supporting virtual VR

Abstract

The present invention relates to the field of image processing technology, and discloses a method and device for obtaining a three-tone land class spot stereoscopic image supporting virtual VR, the method comprising: obtaining vector tile block data corresponding to the three-tone land class spot, and processing the vector tile block data to obtain multiple initial geometric figures, and obtaining the corresponding geographical type; color rendering the corresponding initial geometric figures according to the geographical type to obtain multiple land class spots; combining the land class spots to obtain a two-dimensional texture map, and determining the target land class spot, stretching the target land class spot, and generating a three-tone land class spot stereoscopic image. The present invention processes the vector tile block data to obtain multiple initial geometric figures, and then color rendering each initial geometric figure respectively, and obtains the target land class spot, and finally stretches the target land class spot to generate a three-tone land class spot stereoscopic image with a strong three-dimensional sense and supporting virtual VR display.

Description

Technical Field

[0001] The present invention relates to the field of image processing technology, and in particular to a method, device, equipment and storage medium for obtaining three-dimensional images of land-type patches supporting virtual VR. Background Art

[0002] With the development of society and the progress of science, three-dimensional stereo images are gradually used in all aspects of life, such as watching 3D movies or three-dimensional land imagery. In the prior art, the display method of land image patches is mainly in the form of terrain texture, and the vector rasterized image is attached to the terrain surface as the terrain texture, but the image obtained is essentially a two-dimensional raster image. In this way, the boundaries of land image patches are not obvious, and the attributes of different land image patches can only be distinguished by configuring colors or symbol styles. The three-dimensional sense is not strong, and virtual VR display cannot be supported. Therefore, how to obtain a three-dimensional stereo image of land image patches with a strong three-dimensional sense and support for virtual VR display is a technical problem that needs to be solved urgently.

[0003] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0004] The main purpose of the present invention is to provide a method, device, equipment and storage medium for obtaining stereoscopic images of three-tone land type patches that support virtual VR, aiming to solve the technical problem of how to obtain stereoscopic images of three-tone land type patches with strong three-dimensional sense and support virtual VR display.

[0005] To achieve the above object, the present invention provides a method for obtaining a three-dimensional image of a land-type map patch supporting virtual VR, and the method for obtaining a three-dimensional image of a land-type map patch supporting virtual VR comprises the following steps:

[0006] Acquire vector tile block data corresponding to the three-level land class map, and process the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes a plurality of initial geometric figures;

[0007] Get the geographic type corresponding to each initial geometric figure;

[0008] Color rendering is performed on the corresponding initial geometric figures according to the geographic types to obtain a plurality of land type spots;

[0009] Combining the land type patches to obtain a two-dimensional texture map;

[0010] The target land type patches are determined according to the two-dimensional texture map, and the target land type patches are stretched to generate a three-tone land type patch stereoscopic image.

[0011] Preferably, the step of processing the vector tile block data to obtain an initial geometric image comprises:

[0012] Converting the vector tile block data into spatial data, wherein the spatial data includes point data, line data and surface data;

[0013] An initial geometric image is generated according to the point data, the line data and the surface data.

[0014] Preferably, the step of rendering the corresponding initial geometric figures in color according to the geographical types to obtain a plurality of land type spots comprises:

[0015] The triangulated network corresponding to each initial geometric figure is obtained by using a triangulated network construction algorithm;

[0016] Generate a basic graphics drawing unit according to the triangulated network;

[0017] Search for style configuration files corresponding to the geographic types respectively;

[0018] Color rendering is performed on the corresponding initial geometric figures according to the style configuration file and the basic graphics drawing unit to obtain a plurality of land type patches.

[0019] Preferably, the step of determining the target land type patch according to the two-dimensional texture map comprises:

[0020] Taking the geographic type as a key object, and obtaining a target style identifier corresponding to the key object according to a preset key-value pair;

[0021] The target land type patch is determined according to the target style identifier and the two-dimensional texture map.

[0022] Preferably, the step of stretching the target land type spots to generate a three-tone land type spot stereoscopic image comprises:

[0023] Obtaining a reference vertex coordinate set of the target land-type patch;

[0024] The target land type image patch is longitudinally stretched according to a preset coordinate height threshold to obtain a stretched target land type image patch;

[0025] Obtain a set of stretched vertex coordinates corresponding to the stretched target land-type patch;

[0026] A three-tone land class patch stereoscopic image is generated according to the reference vertex coordinate set and the stretched vertex coordinate set.

[0027] Preferably, the step of generating a three-tone land class patch stereoscopic image according to the reference vertex coordinate set and the stretched vertex coordinate set comprises:

[0028] Constructing a side hole graphic area according to the reference vertex coordinate set and the stretched vertex coordinate set;

[0029] Performing color rendering on the side hole graphic area to obtain a side texture map;

[0030] A three-tone land type patch stereoscopic image is generated according to the stretched target land type patch and the side texture map.

[0031] Preferably, after the step of determining the target land class spots according to the two-dimensional texture map and stretching the target land class spots to generate a three-tone land class spot stereoscopic image, the method further includes:

[0032] Obtain the location information corresponding to the logical camera and the three-level land class map stereo image;

[0033] Determine a position distance of a rendering camera group according to the position information, wherein the rendering camera group includes a first rendering camera and a second rendering camera;

[0034] According to the position distance, a first rendering viewport corresponding to the first rendering camera and a second rendering viewport corresponding to the second rendering camera are respectively set;

[0035] Using the first rendering viewport and the second rendering viewport as target rendering viewports;

[0036] The three-tone land type map stereoscopic image is virtually displayed in VR through the target rendering viewport.

[0037] In addition, to achieve the above-mentioned purpose, the present invention also proposes a three-level land type map spot stereoscopic image acquisition device supporting virtual VR, and the three-level land type map spot stereoscopic image acquisition device supporting virtual VR includes:

[0038] An acquisition module, used for acquiring vector tile block data corresponding to the three-level land type map, and processing the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes a plurality of initial geometric figures;

[0039] The acquisition module is also used to acquire the geographical type corresponding to each initial geometric figure;

[0040] A rendering module, used for rendering the corresponding initial geometric figures in color according to the geographic type to obtain a plurality of land type spots;

[0041] A combination module, used for combining the land type patches to obtain a two-dimensional texture map;

[0042] A generating module is used to determine a target land type patch according to the two-dimensional texture map, and to stretch the target land type patch to generate a three-tone land type patch stereoscopic image.

[0043] In the present invention, firstly, vector tile block data corresponding to three-level land class spots are obtained. In order to speed up data processing efficiency, the vector tile block data can be processed to obtain multiple initial geometric figures, and then the geographical type corresponding to each initial geometric figure is obtained, and the corresponding initial geometric figures are color rendered according to the geographical type to obtain multiple land class spots that are easy to distinguish the geographical types. Then, the land class spots are combined to obtain a two-dimensional texture map. Finally, the target land class spots are determined according to the two-dimensional texture map, and the target land class spots are stretched to generate a three-level land class spot stereoscopic image with a strong three-dimensional sense and supporting virtual VR display. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a flow chart of the first embodiment of the method for obtaining three-level land type patch stereoscopic images supporting virtual VR of the present invention;

[0045] Figure 2 It is a scatter diagram of the preset orientation pixel coordinate set of the first embodiment of the method for obtaining a three-tone land-type patch stereoscopic image supporting virtual VR of the present invention;

[0046] Figure 3 A side hole graphic area diagram of the first embodiment of the method for acquiring three-tone land type patches stereoscopic images supporting virtual VR of the present invention;

[0047] Figure 4 It is a flow chart of a second embodiment of a method for acquiring three-level land type patch stereoscopic images supporting virtual VR according to the present invention;

[0048] Figure 5 It is a structural block diagram of the first embodiment of the device for acquiring three-tone land-type patches stereoscopic images supporting virtual VR according to the present invention.

[0049] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0050] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0051] Reference Figure 1 , Figure 1 It is a flow chart of the first embodiment of the method for obtaining stereoscopic images of three-tone land type spots supporting virtual VR of the present invention, and proposes the first embodiment of the method for obtaining stereoscopic images of three-tone land type spots supporting virtual VR of the present invention.

[0052] In the first embodiment, the method for obtaining a three-dimensional image of a land-type map supporting virtual VR includes the following steps:

[0053] Step S10: acquiring vector tile block data corresponding to the three-level land type patches, and processing the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes a plurality of initial geometric figures.

[0054] It should be noted that the executor of this embodiment is a three-dimensional image acquisition device for three-level land classification spots that supports virtual VR, wherein the device is a three-level land classification spot stereoscopic image acquisition device that supports virtual VR with functions such as image processing, data processing, network communication and program running, and can also be other devices, which is not limited by this embodiment.

[0055] Among them, the "Third National Land Survey" is referred to as the "Third Survey". One of the results of the Third Survey is land classification data, namely, land class spots. That is to say, the land classification data of the Third National Land Survey is called the Third Survey land class spots. Afterwards, the Third Survey land class spot data is obtained based on the Third Survey land class spots, and the Third Survey land class spot data is stored in the database in the form of vector data.

[0056] In order to speed up the display efficiency of data, these vector data are cut into blocks according to certain rules to form vector tile blocks. It can be understood that the current required vector tile coverage is obtained according to the camera cone clipping in the three-dimensional scene, the required vector tile block row and column numbers are calculated according to the vector tile coverage, and the corresponding vector tile block is obtained, and then the corresponding vector tile block data is requested from the database through the data service and saved in the system for caching.

[0057] In addition, the vector tile block data is converted into spatial data, and the spatial data includes point data, line data and surface data. Then, the point data, line data and surface data are combined to obtain an initial geometric image. That is, the vector tile block data is stored in the database in json_encode form. After the client loads it, the json_encode data needs to be parsed, and the string is converted into a memory organization form of points, lines and surfaces. Then, the points, lines and surfaces are combined to obtain an initial geometric image, and the initial geometric image includes multiple initial geometric figures.

[0058] Step S20: Obtain the geographical type corresponding to each initial geometric figure.

[0059] The geographical types corresponding to the initial geometric figures may be the same or different. Assuming that the initial geometric image includes multiple initial geometric figures, the initial geometric figures are triangles, rhombuses, rectangles, etc. In this scheme, the geographical type corresponding to the triangle can be set to a mountain, the geographical type corresponding to the rhombus can be set to land, and the geographical type corresponding to the rectangle can be set to a river, etc. In this scheme, the geographical type corresponding to the triangle can also be set to a mountain, and the geographical type corresponding to the rhombus can also be set to a mountain, etc. This scheme can also pre-set the geographical types corresponding to the initial geometric figures in the database, and match the initial geometric figures in the database to obtain the corresponding geographical types. This embodiment is not limited to this.

[0060] Step S30: color rendering is performed on the corresponding initial geometric figures according to the geographic types to obtain a plurality of land type patches.

[0061] The style configuration files corresponding to the geographic types are searched respectively, and then the triangulated networks corresponding to the initial geometric figures are obtained through the triangulated network construction algorithm. Then the basic graphic drawing units are generated according to the triangulated networks. Finally, the corresponding initial geometric figures are rendered in color according to the style configuration files and the basic graphic drawing units to obtain multiple land type patches.

[0062] That is to say, the three-dimensional land type map is expressed in the form of polygons. The vector tile block data after parsing is stored in the form of initial geometric figures generated by points, lines and surfaces. These initial geometric figures cannot be directly rendered in color through the three-dimensional application programming interface (Application Programming Interface API). Therefore, it is necessary to use the Delaunay triangulation algorithm to generate corresponding triangulated networks for each initial geometric figure, and then form corresponding basic graphic drawing units based on the triangulated networks for the three-dimensional drawing API to call for color rendering.

[0063] It can be understood that, assuming that the initial geometric figure is a rectangle, a triangulated mesh is generated from the rectangle through the Delaunay triangulation algorithm, and the triangulated mesh corresponds to two triangles. Then, a basic graphic drawing unit corresponding to the rectangle is formed according to the obtained triangulated mesh. Assuming that the initial geometric figure is a triangle, a triangulated mesh is generated from the triangle through the Delaunay triangulation algorithm, and then a basic graphic drawing unit corresponding to the triangle is formed according to the obtained triangulated mesh, etc. This embodiment is not limited to this.

[0064] Among them, the geographic types corresponding to the initial geometric figures all have corresponding style identifiers, and the style identifiers have corresponding style configuration files. The style configuration files are user-defined settings, which may include colors, symbols, and transparency, etc. that need to be rendered.

[0065] The geographical type corresponding to the initial geometric figure is used as the key object, and then the style identifier corresponding to the key object is obtained according to the preset key-value pair. The preset key-value pair includes the geographical type and the style identifier. The correspondence between the geographical type and the style identifier is pre-stored in the database in the form of a key-value pair for subsequent retrieval and use. Assuming that the geographical type corresponding to the initial geometric figure is a mountain, and the corresponding style identifier is 1, the style configuration file corresponding to the value 1 is obtained, that is, each geographical type has a corresponding style configuration file, that is, the rendering color and transparency corresponding to the mountain, etc. It can also be assumed that the geographical type corresponding to the initial geometric figure is water, and the corresponding style identifier is 1, then the configuration information such as the rendering color corresponding to water is selected from the style configuration file (the style configuration file contains configuration information corresponding to various geographical types) according to the style identifier, and this embodiment does not limit this.

[0066] Step S40: combining the land type patches to obtain a two-dimensional texture map.

[0067] The ground type patches are initial geometric figures that have been rendered in color. The initial geometric figures after color rendering are combined to obtain an initial geometric image with color. The initial geometric image with color is then called a two-dimensional texture map.

[0068] Assume that the initial geometric image includes triangles, rectangles and rhombuses, and the triangles, rectangles and rhombuses are all colorless graphics. Then, the triangles are rendered in yellow to form yellow triangles, the rectangles are rendered in blue to generate blue rectangles, and the rhombuses are rendered in red to generate red rhombuses. Then, the yellow triangles, blue rectangles and red rhombuses are combined to obtain a two-dimensional texture map, which is the final complete land type map image.

[0069] Step S50: determining a target land class patch according to the two-dimensional texture map, and stretching the target land class patch to generate a three-tone land class patch stereoscopic image.

[0070] The geographic type is used as a key object, and a target style identifier corresponding to the key object is obtained according to a preset key-value pair, and a target land type patch is determined according to the target style identifier and the two-dimensional texture map.

[0071] The geographic type and style identifier corresponding to the initial geometric figure are stored in the database in advance, and the geographic type and style identifier are matched one by one in the form of a key-value pair. That is to say, each geographic type has a corresponding style identifier. Assuming that the initial geometric figure is a triangle, the corresponding geographic type is a mountain, and the corresponding style identifier is 1. Assuming that the initial geometric figure is a rectangle, the corresponding geographic type is water, and the corresponding style identifier is 2, and so on.

[0072] The target land class spots can be determined according to the method of determining the target land class spots in the two-dimensional texture map according to the style identifier or the color. If the user selects the target land class spots with the style identifier of 1, they are the target land class spots corresponding to the triangle. The target land class spots can also be determined by color. If the user selects yellow, the initial geometric figure with yellow color, i.e., the land class spots, will be used as the target land class spots, etc.

[0073] According to the vector tile block data, the vertex pixel coordinate set of the preset orientation corresponding to each initial geometric figure is obtained, and the normal coordinate set corresponding to the target land class spot is obtained according to the vertex pixel coordinate set, and the reference vertex coordinate set of the target land class spot is obtained, and the target land class spot is stretched according to the preset coordinate height threshold, that is, for the polygons corresponding to different land class spots in the same vector tile block, the elevation values ​​of the vertices are set respectively, so that different land class spots can be staggered. Since only the elevation value is modified, the spot polygon is always kept in the same plane, so the normal information does not need to be adjusted, which can reduce the amount of calculation and improve work efficiency, and obtain the stretched target land class spot, and obtain the stretched vertex coordinate set of the target land class spot after stretching, and generate a three-tone land class spot stereo image according to the reference vertex coordinate set and the stretched vertex coordinate set.

[0074] Further, the step of obtaining the normal coordinate set corresponding to each initial geometric figure according to the vertex pixel coordinate set of the first preset orientation includes: the vector tile block data coordinate is a pixel coordinate set with the upper left corner of the tile as the origin, that is, a vertex pixel coordinate set of the preset orientation, such as Figure 2 As shown. Figure 2 This is a scatter plot of the preset orientation pixel coordinate set of the first embodiment of the method for acquiring three-dimensional images of land-type patches supporting virtual VR of the present invention, wherein the preset orientation pixel coordinate set can only meet the use of drawing in a two-dimensional base map, and needs to be drawn with a depth of field effect in a three-dimensional scene, so it needs to be converted into real geographic coordinates. Among them, the coordinate conversion method can be to calculate the longitude and latitude corresponding to the east, west, south and north of the vector tile block through the layer row and column number of the vector tile block through the first preset formula, and then interpolate the longitude and latitude coordinates of each vertex according to the pixel coordinates of each vertex in the vector tile block, and then convert the longitude and latitude coordinates into spatial rectangular coordinates according to the second preset formula, so that the spatial rectangular coordinates are used for three-dimensional scene rendering. That is to say, the vertex pixel coordinate set of the first preset orientation is converted to obtain a spatial rectangular coordinate set, and the normal coordinate set corresponding to each initial geometric figure is obtained according to the spatial rectangular coordinate set.

[0075] The first preset formula is:

[0076] Where L is the level of the vector tile block, Col is the column number of the vector tile block, Row is the row number of the vector tile block, TileSize is the longitude and latitude, West is the west longitude, East is the east longitude, South is the south latitude, and North is the north latitude.

[0077] The second preset formula is:

[0078] Where Latitude Degree is the latitude coordinate, Longitude Degree is the longitude coordinate, x, y, z are the rectangular coordinates in Cartesian space, radCosLat is the defined intermediate variable, and radius is the radius of the earth (the value can be 6378137).

[0079] The step of obtaining the normal coordinate set corresponding to the target land-type patch according to the vertex pixel coordinate set is to perform coordinate transformation on the vertex pixel coordinate set to obtain a spatial rectangular coordinate set, and obtain the normal coordinate set corresponding to the target land-type patch according to the spatial rectangular coordinate set.

[0080] In order to make the solid color vector tiles have a three-dimensional sense in the three-dimensional scene, it is necessary to add lighting information. The brightness changes formed by the undulations of the terrain make the three-dimensional sense stronger. The premise of using lighting is that the vertex must have normal information. First, the face normal information of each triangle is calculated. The calculation method is to select two edges of the triangle to construct a direction vector, and the cross product of these two vectors is used to obtain the face normal of the face. Secondly, the face normal of the triangle is assigned to each vertex of the triangle. A vertex may be shared by multiple triangles, so the normal of the vertex is recorded as the cumulative value of the face normals of all shared triangles. Finally, the accumulated normal value of the vertex is normalized and converted into a unit normal vector and passed to the GPU for lighting calculation.

[0081] refer to Figure 3 , Figure 3 This is a side hole graphic area map of the first embodiment of the method for acquiring a three-tone land type map stereoscopic image supporting virtual VR in the present invention, and then the side hole graphic area is color rendered to obtain a side texture map, and the three-tone land type map stereoscopic image is generated based on the stretched target land type map and the side texture map.

[0082] The side hole graphic area is rendered in color to obtain a side texture map. The step is to generate multiple triangulated meshes from a rectangle of the side hole graphic using a Delaunay triangulated mesh construction algorithm, and then form a basic graphic drawing unit corresponding to the side hole graphic area based on the obtained triangulated mesh. Finally, the side hole graphic area is rendered in color according to the style configuration file corresponding to the side hole graphic area and the basic graphic drawing unit to obtain a side texture map. The color in the style configuration file corresponding to the side hole graphic area can be set to gray, etc. in order to make the three-dimensional image more stereoscopic, and this embodiment is not limited thereto.

[0083] In this scheme, different land type spots in each tile block can also be generated into a stepped three-dimensional triangulated network, and the top surface and the side surface need to be mapped separately. In order to speed up the rendering efficiency, an integrated mapping can be used. Specifically, in the process described in the above embodiment, according to a raster texture that has been rendered and generated, the texture is mapped as a whole to the ups and downs triangulated network to complete the mapping. The specific mapping relationship requires the calculation of the texture coordinates of each vertex. That is, the pixel coordinate value with the upper left corner of the tile as the origin is retained, divided by the size of the vector tile, and the normalized coordinates are obtained. The changed coordinates are used as the texture coordinates of the vertex to complete the mapping of the texture coordinates and the triangulated network. After that, by setting the filtering conditions, different land type spots can be lifted to different heights, but the sudden lifting appears abrupt. Therefore, the height value set by the filtering conditions and the current height value of the land type spot can be directly interpolated, and the height value is adjusted in each frame of rendering to approach the set target value, thereby achieving an animation effect of height lifting or falling, so that the land type spot has a lifting animation process, making the interaction smoother.

[0084] In addition, after the step of determining the target ground class spots according to the two-dimensional texture map and stretching the target ground class spots to generate a three-tone ground class spot stereo image, the position information corresponding to the logical camera and the three-tone ground class spot stereo image are obtained, and the position distance of the rendering camera group is determined according to the position information. The rendering camera group includes a first rendering camera and a second rendering camera. The first rendering viewport corresponding to the first rendering camera and the second rendering viewport corresponding to the second rendering camera are respectively set according to the position distance, and the first rendering viewport and the second rendering viewport are used as target rendering viewports, that is, the three-tone ground class spot stereo image is virtually VR displayed through the target rendering viewport. The specific implementation method of this embodiment can complete the normal rendering operation in the three-dimensional scene, but in order to support the virtual VR display, it is also necessary to expand the rendering capability of supporting stereo pairs. Therefore, three cameras, one logical camera and two rendering cameras, can be set in the three-dimensional scene. In virtual VR display mode, the application can only manipulate the logical camera. The three-dimensional interaction and animation process in the above steps are only linked to the logical camera; the two rendering cameras are consistent with the logical camera in direction, and the positions are offset to the left and right by a certain distance to simulate the pupil distance of the human eye. The rendering cameras are set with corresponding rendering viewports, where the height of the rendering viewport is the height of the screen and the width is half of the screen width. The two viewports are combined to cover the entire rendering screen. When the virtual VR mode is turned off, the rendering camera is removed, and the logical camera is switched to the only rendering camera, which is rendered normally on the screen.

[0085] In this embodiment, vector tile block data corresponding to the three-level land class spots are first obtained. In order to speed up data processing efficiency, the vector tile block data can be processed to obtain multiple initial geometric figures, and then the geographical type corresponding to each initial geometric figure is obtained, and the corresponding initial geometric figures are color rendered according to the geographical type to obtain multiple land class spots that are easy to distinguish the geographical types. Thereafter, the land class spots are combined to obtain a two-dimensional texture map. Finally, the target land class spots are determined according to the two-dimensional texture map, and the target land class spots are stretched. While improving work efficiency, a three-dimensional image of the three-level land class spots with a strong three-dimensional sense and supporting virtual VR display is generated.

[0086] In addition, refer to Figure 4 , Figure 4 Based on the first embodiment of the method for obtaining stereoscopic images of three-tone land classification spots supporting virtual VR, a second embodiment of the method for obtaining stereoscopic images of three-tone land classification spots supporting virtual VR of the present invention is proposed.

[0087] In the second embodiment, the step S50 in the method for obtaining a three-dimensional image of a land-type map supporting virtual VR further includes:

[0088] Step S501: Obtain a set of reference vertex pixel coordinates of the target land-type patch.

[0089] The geographic type is used as a key object, and a target style identifier corresponding to the key object is obtained according to a preset key-value pair, and a target land type patch is determined according to the target style identifier and the two-dimensional texture map.

[0090] The geographic type and style identifier corresponding to the initial geometric figure are stored in the database in advance, and the geographic type and style identifier are matched one by one in the form of a key-value pair. That is to say, each geographic type has a corresponding style identifier. Assuming that the initial geometric figure is a triangle, the corresponding geographic type is a mountain, and the corresponding style identifier is 1. Assuming that the initial geometric figure is a rectangle, the corresponding geographic type is water, and the corresponding style identifier is 2, and so on.

[0091] The target land class spots can be determined according to the method of determining the target land class spots in the two-dimensional texture map according to the style identifier or the color. If the user selects the target land class spots with the style identifier of 1, they are the target land class spots corresponding to the triangle. The target land class spots can also be determined by color. If the user selects yellow, the initial geometric figure with yellow color, i.e., the land class spots, will be used as the target land class spots, etc.

[0092] The vector tile block data coordinates are a set of pixel coordinates with the upper left corner of the tile as the origin, that is, a set of vertex pixel coordinates at a preset orientation, such as Figure 2 As shown. Figure 2 The present invention is a scatter plot of pixel coordinates of preset orientations of the first embodiment of the method for acquiring stereoscopic images of three-dimensional land-type patches supporting virtual VR, wherein the pixel coordinate set of preset orientations can only be used for drawing in a two-dimensional base map, and a drawing with a depth of field effect is required in a three-dimensional scene, so it needs to be converted into real geographic coordinates. Among them, the coordinate conversion method can be to calculate the longitude and latitude corresponding to the east, west, south and north of the vector tile block through the layer row and column number of the vector tile block through the first preset formula, and then interpolate the longitude and latitude coordinates of each vertex according to the pixel coordinates of each vertex in the vector tile block, and then convert the longitude and latitude coordinates into spatial rectangular coordinates according to the second preset formula, so that the spatial rectangular coordinates are used for three-dimensional scene rendering. That is to say, the vertex pixel coordinate set of the first preset orientation is converted to obtain a spatial rectangular coordinate set, and the normal coordinate set corresponding to each initial geometric figure is obtained according to the spatial rectangular coordinate set.

[0093] That is to say, the step of obtaining the normal coordinate set corresponding to the target land-type patch according to the vertex pixel coordinate set is to perform coordinate transformation on the vertex pixel coordinate set to obtain a spatial rectangular coordinate set, and then obtain the normal coordinate set corresponding to the target land-type patch according to the spatial rectangular coordinate set.

[0094] refer to Figure 3 , Figure 3 This is a side hole graphic area diagram of the first embodiment of the method for acquiring stereoscopic images of three-tone land type spots supporting virtual VR in the present invention. The reference vertex pixel coordinate set is B0, B1, B2, B3, B4, B5, and B6. That is to say, the target land type spot is a two-dimensional spot, and the reference vertex pixel coordinate set also refers to the corresponding polygon vertex pixel coordinates in the target land type spot.

[0095] Step S502: longitudinally stretch the target land type patch according to a preset coordinate height threshold to obtain a stretched target land type patch.

[0096] The target land type patch is stretched according to the preset coordinate height threshold, that is, the elevation values ​​of the vertices are set for the polygons corresponding to different land type patches in the same vector tile block, so that different land type patches can be staggered. Since only the elevation value is modified, the patch polygon always remains in the same plane, so the normal information does not need to be adjusted, thereby reducing the amount of calculation and improving work efficiency. Finally, after the stretching is completed, the stretched target land type patch is obtained.

[0097] Step S503: obtaining a set of stretched vertex coordinates corresponding to the stretched target land-type patch.

[0098] Further, refer to Figure 3 , the stretched vertex coordinate set is T0, T1, T2, T3, T4, T5 and T6, that is, since the elevation value of the vertex is changed after stretching, the stretched vertex coordinate values ​​T0, T1, T2, T3, T4, T5 and T6 corresponding to the stretched target land class map are obtained according to the coordinates B0, B1, B2, B3, B4, B5 and B6.

[0099] The stretched target land type patch is the same as the target land type patch, but the height position has changed.

[0100] Step S504: generating a three-tone land-type patch stereoscopic image according to the reference vertex coordinate set and the stretched vertex coordinate set.

[0101] The reference vertex coordinates and the stretched vertex coordinate sets, that is, the coordinates B0, B1, B2, B3, B4, B5 and B6 are connected with the coordinates T0, T1, T2, T3, T4, T5 and T6 in sequence to obtain the side hole graphic area, and then the side hole graphic is generated into multiple triangulated networks by the Delaunay triangulation construction algorithm. The coordinates can also be cross-connected, B0 is connected with T0 and T1, B1 is connected with T1 and T2, B2 is connected with T2 and T3, B3 is connected with T3 and T4, and B4 is connected with T5 and T6. Connect to T4 and T5 respectively, B5 is connected to T5 and T6 respectively, and B6 is connected to T6. Then, a basic graphic drawing unit corresponding to the side hole graphic area is formed according to the obtained triangulated network. Finally, the side hole graphic area is rendered in color according to the style configuration file corresponding to the side hole graphic area and the basic graphic drawing unit to obtain a side texture map. The color in the style configuration file corresponding to the side hole graphic area is used to make the three-dimensional image more stereoscopic. Finally, a three-tone ground class patch stereoscopic image is generated according to the stretched target ground class patch and the side texture map.

[0102] In this embodiment, the reference vertex coordinate set of the target land class spot is first obtained, and then, in order to improve work efficiency, the target land class spot is stretched according to a preset coordinate height threshold to obtain the stretched target land class spot, and the stretched vertex coordinate set corresponding to the stretched target land class spot is obtained. Finally, the target land class spot is generated and stretched according to the reference vertex coordinate set and the stretched vertex coordinate set to generate a three-tone land class spot stereoscopic image with a strong three-dimensional sense.

[0103] In addition, refer to Figure 5 , Figure 5 FIG. 1 is a structural block diagram of the first embodiment of the device for obtaining three-tone land-type spots stereoscopic images supporting virtual VR according to the present invention. Figure 5 As shown, the embodiment of the present invention proposes a three-level land class map stereoscopic image acquisition device supporting virtual VR, including: an acquisition module 5001, used to acquire vector tile block data corresponding to the three-level land class map spots, and process the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes multiple initial geometric figures; the acquisition module 5001 is also used to acquire the geographical type corresponding to each initial geometric figure; a rendering module 5002 is used to color render the corresponding initial geometric figures according to the geographical type, and obtain multiple land class spots; a combination module 5003 is used to combine the land class spots to obtain a two-dimensional texture map; a generation module 5004 is used to determine the target land class spots according to the two-dimensional texture map, and stretch the target land class spots to generate a three-level land class spot stereoscopic image.

[0104] The acquisition module 5001 is used to acquire the vector tile block data corresponding to the three-level land type map, and process the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes multiple initial geometric figures.

[0105] It should be noted that the executor of this embodiment is a three-dimensional image acquisition device for three-level land classification spots that supports virtual VR, wherein the device is a three-level land classification spot stereoscopic image acquisition device that supports virtual VR with functions such as image processing, data processing, network communication and program running, and can also be other devices, which is not limited by this embodiment.

[0106] Among them, the "Third National Land Survey" is referred to as the "Third Survey". One of the results of the Third Survey is land classification data, namely, land class spots. That is to say, the land classification data of the Third National Land Survey is called the Third Survey land class spots. Afterwards, the Third Survey land class spot data is obtained based on the Third Survey land class spots, and the Third Survey land class spot data is stored in the database in the form of vector data.

[0107] In order to speed up the display efficiency of data, these vector data are cut into blocks according to certain rules to form vector tile blocks. It can be understood that the current required vector tile coverage is obtained according to the camera cone clipping in the three-dimensional scene, the required vector tile block row and column numbers are calculated according to the vector tile coverage, and the corresponding vector tile block is obtained, and then the corresponding vector tile block data is requested from the database through the data service and saved in the system for caching.

[0108] In addition, the vector tile block data is converted into spatial data, and the spatial data includes point data, line data and surface data. Then, the point data, line data and surface data are combined to obtain an initial geometric image. That is, the vector tile block data is stored in the database in json_encode form. After the client loads it, the json_encode data needs to be parsed, and the string is converted into a memory organization form of points, lines and surfaces. Then, the points, lines and surfaces are combined to obtain an initial geometric image, and the initial geometric image includes multiple initial geometric figures.

[0109] The acquisition module 5001 is also used to acquire the geographical type corresponding to each initial geometric figure.

[0110] The geographical types corresponding to the initial geometric figures may be the same or different. Assuming that the initial geometric image includes multiple initial geometric figures, the initial geometric figures are triangles, rhombuses, rectangles, etc. In this scheme, the geographical type corresponding to the triangle can be set to a mountain, the geographical type corresponding to the rhombus can be set to land, and the geographical type corresponding to the rectangle can be set to a river, etc. In this scheme, the geographical type corresponding to the triangle can also be set to a mountain, and the geographical type corresponding to the rhombus can also be set to a mountain, etc. This scheme can also pre-set the geographical types corresponding to the initial geometric figures in the database, and match the initial geometric figures in the database to obtain the corresponding geographical types. This embodiment is not limited to this.

[0111] The rendering module 5002 is used to perform color rendering on the corresponding initial geometric figures according to the geographical types to obtain multiple land type patches.

[0112] The style configuration files corresponding to the geographic types are searched respectively, and then the triangulated networks corresponding to the initial geometric figures are obtained through the triangulated network construction algorithm. Then the basic graphic drawing units are generated according to the triangulated networks. Finally, the corresponding initial geometric figures are rendered in color according to the style configuration files and the basic graphic drawing units to obtain multiple land type patches.

[0113] That is to say, the three-dimensional land type map is expressed in the form of polygons. The vector tile block data after parsing is stored in the form of initial geometric figures generated by points, lines and surfaces. These initial geometric figures cannot be directly rendered in color through the three-dimensional application programming interface (Application Programming Interface API). Therefore, it is necessary to use the Delaunay triangulation algorithm to generate corresponding triangulated networks for each initial geometric figure, and then form corresponding basic graphic drawing units based on the triangulated networks for the three-dimensional drawing API to call for color rendering.

[0114] It can be understood that, assuming that the initial geometric figure is a rectangle, a triangulated mesh is generated from the rectangle through the Delaunay triangulation algorithm, and the triangulated mesh corresponds to two triangles. Then, a basic graphic drawing unit corresponding to the rectangle is formed according to the obtained triangulated mesh. Assuming that the initial geometric figure is a triangle, a triangulated mesh is generated from the triangle through the Delaunay triangulation algorithm, and then a basic graphic drawing unit corresponding to the triangle is formed according to the obtained triangulated mesh, etc. This embodiment is not limited to this.

[0115] Among them, the geographic types corresponding to the initial geometric figures all have corresponding style identifiers, and the style identifiers have corresponding style configuration files. The style configuration files are user-defined settings, which may include colors, symbols, and transparency, etc. that need to be rendered.

[0116] The geographical type corresponding to the initial geometric figure is used as the key object, and then the style identifier corresponding to the key object is obtained according to the preset key-value pair. The preset key-value pair includes the geographical type and the style identifier. The correspondence between the geographical type and the style identifier is pre-stored in the database in the form of a key-value pair for subsequent retrieval and use. Assuming that the geographical type corresponding to the initial geometric figure is a mountain, and the corresponding style identifier is 1, the style configuration file corresponding to the value 1 is obtained, that is, each geographical type has a corresponding style configuration file, that is, the rendering color and transparency corresponding to the mountain, etc. It can also be assumed that the geographical type corresponding to the initial geometric figure is water, and the corresponding style identifier is 1, then the configuration information such as the rendering color corresponding to water is selected from the style configuration file (the style configuration file contains configuration information corresponding to various geographical types) according to the style identifier, and this embodiment does not limit this.

[0117] The combination module 5003 is used to combine the land type patches to obtain a two-dimensional texture map.

[0118] The ground type patches are initial geometric figures that have been rendered in color. The initial geometric figures after color rendering are combined to obtain an initial geometric image with color. The initial geometric image with color is then called a two-dimensional texture map.

[0119] Assume that the initial geometric image includes triangles, rectangles and rhombuses, and the triangles, rectangles and rhombuses are all colorless graphics. Then, the triangles are rendered in yellow to form yellow triangles, the rectangles are rendered in blue to generate blue rectangles, and the rhombuses are rendered in red to generate red rhombuses. Then, the yellow triangles, blue rectangles and red rhombuses are combined to obtain a two-dimensional texture map, which is the final complete land type map image.

[0120] The generating module 5004 is used to determine the target land type spots according to the two-dimensional texture map, and stretch the target land type spots to generate a three-tone land type spot stereoscopic image.

[0121] The geographic type is used as a key object, and a target style identifier corresponding to the key object is obtained according to a preset key-value pair, and a target land type patch is determined according to the target style identifier and the two-dimensional texture map.

[0122] The geographic type and style identifier corresponding to the initial geometric figure are stored in the database in advance, and the geographic type and style identifier are matched one by one in the form of a key-value pair. That is to say, each geographic type has a corresponding style identifier. Assuming that the initial geometric figure is a triangle, the corresponding geographic type is a mountain, and the corresponding style identifier is 1. Assuming that the initial geometric figure is a rectangle, the corresponding geographic type is water, and the corresponding style identifier is 2, and so on.

[0123] The target land class spots can be determined according to the method of determining the target land class spots in the two-dimensional texture map according to the style identifier or the color. If the user selects the target land class spots with the style identifier of 1, they are the target land class spots corresponding to the triangle. The target land class spots can also be determined by color. If the user selects yellow, the initial geometric figure with yellow color, i.e., the land class spots, will be used as the target land class spots, etc.

[0124] According to the vector tile block data, the vertex pixel coordinate set of the preset orientation corresponding to each initial geometric figure is obtained, and the normal coordinate set corresponding to the target land class spot is obtained according to the vertex pixel coordinate set, and the reference vertex coordinate set of the target land class spot is obtained, and the target land class spot is stretched according to the preset coordinate height threshold, that is, for the polygons corresponding to different land class spots in the same vector tile block, the elevation values ​​of the vertices are set respectively, so that different land class spots can be staggered. Since only the elevation value is modified, the spot polygon is always kept in the same plane, so the normal information does not need to be adjusted, which can reduce the amount of calculation and improve work efficiency, and obtain the stretched target land class spot, and obtain the stretched vertex coordinate set of the target land class spot after stretching, and generate a three-tone land class spot stereo image according to the reference vertex coordinate set and the stretched vertex coordinate set.

[0125] Further, the step of obtaining the normal coordinate set corresponding to each initial geometric figure according to the vertex pixel coordinate set of the first preset orientation includes: the vector tile block data coordinate is a pixel coordinate set with the upper left corner of the tile as the origin, that is, a vertex pixel coordinate set of the preset orientation, such as Figure 2 As shown. Figure 2 This is a scatter plot of the preset orientation pixel coordinate set of the first embodiment of the method for acquiring three-dimensional images of land-type patches supporting virtual VR of the present invention, wherein the preset orientation pixel coordinate set can only meet the use of drawing in a two-dimensional base map, and needs to be drawn with a depth of field effect in a three-dimensional scene, so it needs to be converted into real geographic coordinates. Among them, the coordinate conversion method can be to calculate the longitude and latitude corresponding to the east, west, south and north of the vector tile block through the layer row and column number of the vector tile block through the first preset formula, and then interpolate the longitude and latitude coordinates of each vertex according to the pixel coordinates of each vertex in the vector tile block, and then convert the longitude and latitude coordinates into spatial rectangular coordinates according to the second preset formula, so that the spatial rectangular coordinates are used for three-dimensional scene rendering. That is to say, the vertex pixel coordinate set of the first preset orientation is converted to obtain a spatial rectangular coordinate set, and the normal coordinate set corresponding to each initial geometric figure is obtained according to the spatial rectangular coordinate set.

[0126] The first preset formula is:

[0127] Where L is the level of the vector tile block, Col is the column number of the vector tile block, Row is the row number of the vector tile block, TileSize is the longitude and latitude, West is the west longitude, East is the east longitude, South is the south latitude, and North is the north latitude.

[0128] The second preset formula is:

[0129] Where Latitude Degree is the latitude coordinate, Longitude Degree is the longitude coordinate, x, y, z are the rectangular coordinates in Cartesian space, radCosLat is the defined intermediate variable, and radius is the radius of the earth (the value can be 6378137).

[0130] The step of obtaining the normal coordinate set corresponding to the target land-type patch according to the vertex pixel coordinate set is to perform coordinate transformation on the vertex pixel coordinate set to obtain a spatial rectangular coordinate set, and obtain the normal coordinate set corresponding to the target land-type patch according to the spatial rectangular coordinate set.

[0131] In order to make the solid color vector tiles have a three-dimensional sense in the three-dimensional scene, it is necessary to add lighting information. The brightness changes formed by the undulations of the terrain make the three-dimensional sense stronger. The premise of using lighting is that the vertex must have normal information. First, the face normal information of each triangle is calculated. The calculation method is to select two edges of the triangle to construct a direction vector, and the cross product of these two vectors is used to obtain the face normal of the face. Secondly, the face normal of the triangle is assigned to each vertex of the triangle. A vertex may be shared by multiple triangles, so the normal of the vertex is recorded as the cumulative value of the face normals of all shared triangles. Finally, the accumulated normal value of the vertex is normalized and converted into a unit normal vector and passed to the GPU for lighting calculation.

[0132] refer to Figure 3 , Figure 3 This is a side hole graphic area map of the first embodiment of the method for acquiring a three-tone land type map stereoscopic image supporting virtual VR in the present invention, and then the side hole graphic area is color rendered to obtain a side texture map, and the three-tone land type map stereoscopic image is generated based on the stretched target land type map and the side texture map.

[0133] The side hole graphic area is rendered in color to obtain a side texture map. The step is to generate multiple triangulated meshes from a rectangle of the side hole graphic using a Delaunay triangulated mesh construction algorithm, and then form a basic graphic drawing unit corresponding to the side hole graphic area based on the obtained triangulated mesh. Finally, the side hole graphic area is rendered in color according to the style configuration file corresponding to the side hole graphic area and the basic graphic drawing unit to obtain a side texture map. The color in the style configuration file corresponding to the side hole graphic area can be set to gray, etc. in order to make the three-dimensional image more stereoscopic, and this embodiment is not limited thereto.

[0134] In this scheme, different land type spots in each tile block can also be generated into a stepped three-dimensional triangulated network, and the top surface and the side surface need to be mapped separately. In order to speed up the rendering efficiency, an integrated mapping can be used. Specifically, in the process described in the above embodiment, according to a raster texture that has been rendered and generated, the texture is mapped as a whole to the ups and downs triangulated network to complete the mapping. The specific mapping relationship requires the calculation of the texture coordinates of each vertex. That is, the pixel coordinate value with the upper left corner of the tile as the origin is retained, divided by the size of the vector tile, and the normalized coordinates are obtained. The changed coordinates are used as the texture coordinates of the vertex to complete the mapping of the texture coordinates and the triangulated network. After that, by setting the filtering conditions, different land type spots can be lifted to different heights, but the sudden lifting appears abrupt. Therefore, the height value set by the filtering conditions and the current height value of the land type spot can be directly interpolated, and the height value is adjusted in each frame of rendering to approach the set target value, thereby achieving an animation effect of height lifting or falling, so that the land type spot has a lifting animation process, making the interaction smoother.

[0135] In addition, after the step of determining the target ground class spots according to the two-dimensional texture map and stretching the target ground class spots to generate a three-tone ground class spot stereo image, the position information corresponding to the logical camera and the three-tone ground class spot stereo image are obtained, and the position distance of the rendering camera group is determined according to the position information. The rendering camera group includes a first rendering camera and a second rendering camera. The first rendering viewport corresponding to the first rendering camera and the second rendering viewport corresponding to the second rendering camera are respectively set according to the position distance, and the first rendering viewport and the second rendering viewport are used as target rendering viewports, that is, the three-tone ground class spot stereo image is virtually VR displayed through the target rendering viewport. The specific implementation method of this embodiment can complete the normal rendering operation in the three-dimensional scene, but in order to support the virtual VR display, it is also necessary to expand the rendering capability of supporting stereo pairs. Therefore, three cameras, one logical camera and two rendering cameras, can be set in the three-dimensional scene. In virtual VR display mode, the application can only manipulate the logical camera. The three-dimensional interaction and animation process in the above steps are only linked to the logical camera; the two rendering cameras are consistent with the logical camera in direction, and the positions are offset to the left and right by a certain distance to simulate the pupil distance of the human eye. The rendering cameras are set with corresponding rendering viewports, where the height of the rendering viewport is the height of the screen and the width is half of the screen width. The two viewports are combined to cover the entire rendering screen. When the virtual VR mode is turned off, the rendering camera is removed, and the logical camera is switched to the only rendering camera, which is rendered normally on the screen.

[0136] In this embodiment, vector tile block data corresponding to the three-level land class spots are first obtained. In order to speed up data processing efficiency, the vector tile block data can be processed to obtain multiple initial geometric figures, and then the geographical type corresponding to each initial geometric figure is obtained, and the corresponding initial geometric figures are color rendered according to the geographical type to obtain multiple land class spots that are easy to distinguish the geographical types. Thereafter, the land class spots are combined to obtain a two-dimensional texture map. Finally, the target land class spots are determined according to the two-dimensional texture map, and the target land class spots are stretched. While improving work efficiency, a three-dimensional image of the three-level land class spots with a strong three-dimensional sense and supporting virtual VR display is generated.

[0137] Other embodiments or specific implementation methods of the device for obtaining three-tone land type patches stereoscopic images supporting virtual VR of the present invention can refer to the above-mentioned method embodiments and will not be described in detail here.

[0138] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0139] The serial numbers of the embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. In a unit claim that lists several means, several of these means may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order and these words may be interpreted as names.

[0140] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory image (ROM) / random access memory (RAM), a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0141] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for obtaining three-dimensional images of land-type patches supporting virtual VR, characterized in that: The method comprises the following steps: Acquire vector tile block data corresponding to the three-level land class map, and process the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes a plurality of initial geometric figures; Get the geographic type corresponding to each initial geometric figure; Color rendering is performed on the corresponding initial geometric figures according to the geographic types to obtain a plurality of land type spots; Combining the land type patches to obtain a two-dimensional texture map; Determine a target land class patch according to the two-dimensional texture map, and stretch the target land class patch to generate a three-tone land class patch stereoscopic image; The step of stretching the target land type spots to generate a three-tone land type spot stereoscopic image includes: Acquire a set of vertex pixel coordinates of a preset orientation corresponding to each initial geometric figure according to the vector tile block data; Obtain a normal coordinate set corresponding to the target land-type patch according to the vertex pixel coordinate set, and obtain a reference vertex coordinate set of the target land-type patch; The target land type image patch is longitudinally stretched according to a preset coordinate height threshold to obtain a stretched target land type image patch; Obtain a set of stretched vertex coordinates corresponding to the stretched target land-type patch; Generate a three-tone land class patch stereo image according to the reference vertex coordinate set and the stretched vertex coordinate set; The step of obtaining a normal coordinate set corresponding to the target land-type patch according to the vertex pixel coordinate set includes: Performing coordinate transformation on the vertex pixel coordinate set to obtain a spatial rectangular coordinate set; Acquire a normal coordinate set corresponding to the target land type patch according to the spatial rectangular coordinate set; The coordinate conversion method is as follows: The longitude and latitude corresponding to the east, west, south and north of the vector tile block are calculated by a first preset formula according to the layer row and column number of the vector tile block, and the longitude and latitude coordinates of each vertex are obtained by interpolation according to the pixel coordinates of each vertex in the vector tile block, and the longitude and latitude coordinates are converted into spatial rectangular coordinates according to a second preset formula, so that the spatial rectangular coordinates are used for three-dimensional scene rendering; The first preset formula is: Where L is the level of the vector tile block, Col is the column number of the vector tile block, Row is the row number of the vector tile block, TileSize is the longitude and latitude, West is the west longitude, East is the east longitude, South is the south latitude, and North is the north latitude; The second preset formula is: Where Latitude Degree is the latitude coordinate, Longitude Degree is the longitude coordinate, x, y, z are the rectangular coordinates in Cartesian space, radCosLat is the defined intermediate variable, and radius is the radius of the earth.

2. The method according to claim 1, characterized in that The step of processing the vector tile block data to obtain an initial geometric image comprises: Converting the vector tile block data into spatial data, wherein the spatial data includes point data, line data and surface data; An initial geometric image is generated according to the point data, the line data and the surface data.

3. The method according to claim 1, characterized in that The step of rendering the corresponding initial geometric figures in color according to the geographical types to obtain a plurality of land type spots comprises: The triangulated network corresponding to each initial geometric figure is obtained by using a triangulated network construction algorithm; Generate a basic graphics drawing unit according to the triangulated network; Search for style configuration files corresponding to the geographic types respectively; According to the style configuration file, the basic graphics drawing unit performs color rendering on the initial geometric graphics to obtain a plurality of land type patches.

4. The method according to claim 1, characterized in that The step of determining the target land type patch according to the two-dimensional texture map comprises: Using the geographic type as a key object, searching for a corresponding target style identifier in a preset key-value pair, wherein the key-value pair stores a corresponding relationship between the geographic type and the style identifier; The target land type patch is determined according to the target style identifier and the two-dimensional texture map.

5. The method according to claim 1, characterized in that The step of generating a three-tone land class spot stereoscopic image according to the reference vertex coordinate set and the stretched vertex coordinate set comprises: Constructing a side hole graphic area according to the reference vertex coordinate set and the stretched vertex coordinate set; Performing color rendering on the side hole graphic area to obtain a side texture map; A three-tone land type patch stereoscopic image is generated according to the stretched target land type patch and the side texture map.

6. The method according to claim 1, characterized in that After the step of determining the target land class spots according to the two-dimensional texture map and stretching the target land class spots to generate a three-tone land class spot stereoscopic image, the method further includes: Obtain the location information corresponding to the logical camera and the three-level land class map stereo image; Determine a position distance of a rendering camera group according to the position information, wherein the rendering camera group includes a first rendering camera and a second rendering camera; According to the position distance, a first rendering viewport corresponding to the first rendering camera and a second rendering viewport corresponding to the second rendering camera are respectively set; Using the first rendering viewport and the second rendering viewport as target rendering viewports; The three-tone land type map stereoscopic image is virtually displayed in VR through the target rendering viewport.

7. A three-dimensional image acquisition device for three-level land type spots supporting virtual VR, characterized in that: The three-level land type map stereoscopic image acquisition device supporting virtual VR includes: An acquisition module, used for acquiring vector tile block data corresponding to the three-level land type map, and processing the vector tile block data to obtain an initial geometric image, wherein the initial geometric image includes a plurality of initial geometric figures; The acquisition module is also used to acquire the geographical type corresponding to each initial geometric figure; A rendering module, used for rendering the corresponding initial geometric figures in color according to the geographic type to obtain a plurality of land type spots; A combination module, used for combining the land type patches to obtain a two-dimensional texture map; A generating module, used for determining a target land class spot according to the two-dimensional texture map, and stretching the target land class spot to generate a three-tone land class spot stereo image; The generation module is further used to obtain a vertex pixel coordinate set of a preset orientation corresponding to each initial geometric figure according to the vector tile block data; obtain a normal coordinate set corresponding to the target land class spot according to the vertex pixel coordinate set, and obtain a reference vertex coordinate set of the target land class spot; longitudinally stretch the target land class spot according to a preset coordinate height threshold to obtain the stretched target land class spot; obtain a stretched vertex coordinate set corresponding to the stretched target land class spot; and generate a three-tone land class spot stereoscopic image according to the reference vertex coordinate set and the stretched vertex coordinate set; The generating module is further used to perform coordinate conversion on the vertex pixel coordinate set to obtain a spatial rectangular coordinate set; and obtain a normal coordinate set corresponding to the target land-type patch according to the spatial rectangular coordinate set; The coordinate conversion method is as follows: The longitude and latitude corresponding to the east, west, south and north of the vector tile block are calculated by a first preset formula according to the layer row and column number of the vector tile block, and the longitude and latitude coordinates of each vertex are obtained by interpolation according to the pixel coordinates of each vertex in the vector tile block, and the longitude and latitude coordinates are converted into spatial rectangular coordinates according to a second preset formula, so that the spatial rectangular coordinates are used for three-dimensional scene rendering; The first preset formula is: Where L is the level of the vector tile block, Col is the column number of the vector tile block, Row is the row number of the vector tile block, TileSize is the longitude and latitude, West is the west longitude, East is the east longitude, South is the south latitude, and North is the north latitude; The second preset formula is: Where Latitude Degree is the latitude coordinate, Longitude Degree is the longitude coordinate, x, y, z are the rectangular coordinates in Cartesian space, radCosLat is the defined intermediate variable, and radius is the radius of the earth.

Images