Map tile data downloading method and device and storage medium

Abstract

The invention provides a map tile data downloading method and device and a storage medium, and relates to the technical field of map data processing. The map tile data downloading method comprises the following steps: receiving a target map level in a map level range of a map display target area and a resolution ratio of a map display interface; obtaining a target ground resolution corresponding to the target map level based on a preset corresponding relation between the map level and the ground resolution; obtaining a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; and obtaining the contour of the map display target area, and expanding the contour of the map display target area based on a contour expansion algorithm and the physical length corresponding to the target pixel to obtain a map downloading area contour so as to download corresponding map tile data in the map downloading area contour.

Description

Technical Field

[0001] The present invention relates to the technical field of map data processing, and in particular to a method, device and storage medium for downloading map tile data. Background Art

[0002] Map tile technology is the foundation of modern map services and geographic information system applications. It divides map data into multiple small blocks. Each map tile is equivalent to a standard unit of the entire map data, providing an efficient and flexible way to manage and display geospatial data.

[0003] When downloading map tile data to display the map display target area in the map display interface, if the downloaded map tile data only includes the map tile data of the map display target area, when viewing the map at the global map level in the map display interface, the outline of the map display target area will be displayed blank, affecting the aesthetics of the system. If the scope corresponding to the downloaded map tile data is expanded to display information outside the scope of the map display target area, a large amount of additional map tile data needs to be downloaded, which will cause the amount of map tile data to be downloaded to increase exponentially, and the download time and disk space occupied by the map tile data will also increase exponentially. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a method, device and storage medium for downloading map tile data.

[0005] The present invention provides a method for downloading map tile data, comprising: receiving a target map level in a map level range of a map display target area and a resolution of a map display interface; acquiring a target ground resolution corresponding to the target map level based on a preset corresponding relationship between the map level and the ground resolution; acquiring a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; acquiring an outline of the map display target area, expanding the outline of the map display target area based on an outline expansion algorithm and the physical length corresponding to the target pixel, and obtaining a map download area outline, so as to download the map tile data corresponding to the map download area outline.

[0006] According to a map tile data downloading method provided by the present invention, the physical length corresponding to the target pixel of the map display interface is obtained according to the target map level, the resolution of the map display interface and the target ground resolution, including: obtaining the number of long-side pixels of the map display interface resolution; confirming that the center of the map display interface is within the outline of the map display target area, obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the number of long-side pixels and the target ground resolution; wherein the target map level is an exponential coefficient.

[0007] According to a map tile data downloading method provided by the present invention, after obtaining the number of long side pixels of the map display interface resolution, the method further includes: confirming that the center of the map display interface is on the outline of the map display target area, obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the half value of the number of long side pixels and the target ground resolution; wherein the map level is an exponential coefficient.

[0008] According to a map tile data downloading method provided by the present invention, before obtaining the target ground resolution corresponding to the target map level based on the preset correspondence between the map level and the ground resolution, the method also includes: obtaining a comparison table of map levels and ground resolutions; wherein the preset correspondence between the map level and the ground resolution is stored in the comparison table; based on the preset correspondence between the map level and the ground resolution, obtaining the target ground resolution corresponding to the target map level includes: searching in the comparison table based on the target map level to obtain the target ground resolution corresponding to the target map level.

[0009] According to a map tile data downloading method provided by the present invention, the outline of the map display target area is obtained, and the outline of the map display target area is expanded based on an outline expansion algorithm and a physical length corresponding to the target pixel to obtain a map download area outline, so as to download the map tile data corresponding to the map download area outline, including: obtaining the outline of the map display target area, using the outline expansion algorithm to expand the outline of the map display target area by the physical length corresponding to the target pixel to obtain the map download area outline; determining a map tile number based on the map download area outline and the corresponding map level; obtaining a server access address of the map tile data, concatenating the server access address and the map tile number to obtain a download address of the map tile data; and downloading the map tile data corresponding to the map download area outline based on the download address.

[0010] According to a map tile data downloading method provided by the present invention, after downloading the map tile data corresponding to the map download area outline, the method also includes: repeating the step of obtaining the map download area outline to download the map tile data corresponding to the map area within the map download area outline, obtaining the map download area outline corresponding to each remaining map level in the map level range, and downloading the map tile data corresponding to the corresponding map download area outlines respectively.

[0011] The present invention also provides a map tile data downloading device, comprising: a receiving module, used to receive a target map level in a map level range of a map display target area and a resolution of a map display interface; a ground resolution acquisition module, used to acquire a target ground resolution corresponding to the target map level based on a preset correspondence between the map level and the ground resolution; a pixel point physical length acquisition module, used to acquire a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; a first map tile data downloading module, used to acquire an outline of the map display target area, expand the outline of the map display target area based on an outline expansion algorithm and the physical length corresponding to the target pixel, obtain a map download area outline, and download the corresponding map tile data within the map download area outline.

[0012] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the map tile data downloading method described above is implemented.

[0013] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the map tile data downloading method as described in any one of the above is implemented.

[0014] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the map tile data downloading method described above is implemented.

[0015] The map tile data downloading method, device and storage medium provided by the present invention can obtain the target ground resolution according to the target map level in the map display target area map level range, obtain the physical length corresponding to the target pixel of the map display interface based on the target map level, the resolution of the map display interface and the target ground resolution, and obtain the map download area outline in combination with the physical length corresponding to the target pixel and the outline expansion algorithm. In this way, through the relevant parameters of the aforementioned map display, the map tile data corresponding to the map download area outline can be obtained according to actual needs, thereby reducing the amount of map tile data required to display map information outside the map display target area when viewing the map at a smaller map level, thereby avoiding the exponential growth of the amount of map tile data that needs to be downloaded, and reducing the download time and disk space occupied by the map tile data. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a flow chart of the map tile data downloading method provided by the present invention.

[0018] Figure 2 It is a schematic diagram of a map display target area in the map tile data downloading method provided by the present invention.

[0019] Figure 3 It is a schematic diagram of a map download area in the map tile data downloading method provided by the present invention.

[0020] Figure 4 It is a comparison table of map level and ground resolution in the map tile data downloading method provided by the present invention.

[0021] Figure 5 It is a structural schematic diagram of the map tile data downloading device provided by the present invention.

[0022] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Combine the following Figure 1-Figure 6 The present invention describes a map tile data downloading method, device and storage medium.

[0025] Figure 1 FIG. 1 is a flow chart of a method for downloading map tile data provided by the present invention. Figure 1 As shown, the method includes: Step 110: Receive a target map level in a map level range of a map display target area and a resolution of a map display interface.

[0026] like Figure 2 As shown, the map display target area refers to a specific geographical area that the user wants to display in the map display interface, for example, the map display target area is Beijing or Tianjin.

[0027] The map level range refers to the interval of different map levels used when displaying a map. The map level refers to the zoom level of the map. Different levels represent different zoom levels of the map. They can also be called zoom levels or scale levels. For example, the map level range may include map levels 5-18. The target map level is a map level in the map level range. It is the specific map level that the user wants the map to reach.

[0028] In one embodiment, a smaller map level may be used in the map level range to represent a map with a larger display area but fewer details, and a larger map level may be used to represent a map with a smaller display area but richer details. In another embodiment, a smaller map level may be used in the map level range to represent a map with a smaller display area but richer details, and a larger map level may be used to represent a map with a larger display area but fewer details.

[0029] Exemplarily, the map display target area and the target map level in the map display target area map level range can be obtained by receiving user input instructions, and the user input instructions corresponding to the target map level in the map display target area map level range can be generated by pinching and expanding gestures.

[0030] Step 120: Based on a preset correspondence between map level and ground resolution, obtain a target ground resolution corresponding to the target map level.

[0031] Ground resolution refers to the actual size of the ground represented by a pixel in the map display interface. For example, the ground resolution can be the actual distance on the ground represented by a pixel in the map display interface, and the unit can be meters. It is understandable that the map level of the target area displayed on the map is different, and the corresponding ground resolution is also different. The target ground resolution is the ground resolution that the user wants the map to reach a specific map level. Exemplarily, each map level can correspond to a specific ground resolution.

[0032] Step 130: Acquire a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface, and the target ground resolution.

[0033] The ground resolution and the physical length corresponding to the target pixel of the map display interface are both related to the physical size of the map, but the ground resolution is a static indicator that describes the degree of map detail, while the physical length corresponding to the target pixel of the map display interface is a dynamically calculated parameter used to determine the download range of the map.

[0034] Step 140, obtaining the outline of the map display target area, expanding the outline of the map display target area based on the outline expansion algorithm and the physical length corresponding to the target pixel, obtaining the map download area outline, and downloading the map tile data corresponding to the map download area outline.

[0035] Exemplarily, after the map display target area is determined, the outline of the map display target area may be acquired based on an outline determination algorithm.

[0036] It is understandable that the map tile data corresponding to the outline of the map download area includes the map tile data corresponding to the outline. Figure 3 As shown, the map display target area and its outline are within the map download area outline, so the map tile data corresponding to the map download area outline is downloaded, including the map tile data corresponding to the map display target area outline. In this way, when viewing the map at a smaller map level, map information can still be displayed outside the map display target area instead of displaying a blank area, which can increase the aesthetics of the map display and improve the user experience.

[0037] The map tile data downloading method provided by the embodiment of the present invention can obtain the target ground resolution according to the target map level in the map level range of the map display target area, obtain the physical length corresponding to the target pixel of the map display interface based on the target map level, the resolution of the map display interface and the target ground resolution, and obtain the map download area outline in combination with the physical length corresponding to the target pixel and the outline expansion algorithm. In this way, through the relevant parameters of the aforementioned map display, the map tile data corresponding to the map download area outline can be obtained according to actual needs, thereby reducing the amount of map tile data required to display map information outside the map display target area when viewing the map at a smaller map level, thereby avoiding the exponential growth of the amount of map tile data that needs to be downloaded, and reducing the download time and disk space occupied by the map tile data.

[0038] Based on the above embodiment, step 130, obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution, includes: obtaining the number of long side pixels of the map display interface resolution; confirming that the center of the map display interface is within the outline of the map display target area, obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the number of long side pixels and the target ground resolution; wherein the target map level is an exponential coefficient.

[0039] The map display interface resolution refers to the resolution of the device that provides the map display interface. The resolution refers to the number of pixels that can be displayed on the device screen, generally expressed in pixels of width and height, such as the resolution of 1920×1080. The number of pixels on the long side can be the larger of the number of pixels of width and height, for example, in the resolution of 1920×1080, the number of pixels on the long side is 1920.

[0040] There are two relationships between the center of the map display interface and the outline of the map display target area: the center of the map display interface is on the outline of the map display target area, or the center of the map display interface is within the outline of the map display target area.

[0041] The physical length corresponding to the target pixel of the map display interface obtained based on the number of long-side pixels is greater than the physical length corresponding to the target pixel of the map display interface obtained based on the number of short-side pixels. Thus, in this embodiment, the map download area outline obtained based on the physical length corresponding to the target pixel of the map display interface obtained based on the number of long-side pixels, the target map level and the target ground resolution, and the map tile data obtained can satisfy the map display interface in scenarios such as horizontal and vertical screen switching or map rotation of the device of the map display interface, and the map will always be displayed in the map display interface without any blank spaces.

[0042] For example, the physical length corresponding to the target pixel may be the physical length corresponding to the number of long-side pixels of 1920. At this time, the physical length corresponding to the target pixel of the map display interface can be obtained based on the following formula, the target map level, the number of long-side pixels and the target ground resolution:

[0043] in, The physical length corresponding to the target pixel of the map display interface; is the number of pixels on the long side; is the target ground resolution; The target map level.

[0044] Based on any of the above embodiments, after obtaining the number of long side pixels of the map display interface resolution, the method further includes: confirming that the center of the map display interface is on the outline of the target area displayed on the map, and obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the half value of the number of long side pixels and the target ground resolution; wherein the map level is an exponential coefficient.

[0045] In this way, in this embodiment, the map download area outline is obtained based on the physical length corresponding to the target pixel of the map display interface obtained based on the half value of the long side pixel number, the target map level and the target ground resolution, and the map tile data obtained can meet the requirements of the map display interface device switching between horizontal and vertical screens or rotating the map, and the map display interface always displays the map without blank spaces.

[0046] The map download area outline obtained based on the half value of the long side pixel number is obviously smaller than the map download area outline obtained based on the long side pixel number. In this way, the map tile data corresponding to the map download area outline corresponding to the half value of the long side pixel number is obviously smaller than the map tile data corresponding to the map download area outline corresponding to the long side pixel number. This can further reduce the amount of map tile data required to be added while meeting the needs.

[0047] For example, the physical length corresponding to the target pixel may be the physical length corresponding to half the value of the number of pixels on the long side. In this case, the target map level, the half value of the number of pixels on the long side, and the target ground resolution may be used to obtain the physical length corresponding to the target pixel on the map display interface based on the following formula:

[0048] in, The physical length corresponding to the target pixel of the map display interface; is half the number of pixels on the long side; is the target ground resolution; The target map level.

[0049] Based on any of the above embodiments, before step S120 obtains the target ground resolution corresponding to the target map level based on the preset correspondence between the map level and the ground resolution, the method further includes: obtaining a comparison table of map levels and ground resolutions; wherein the comparison table stores the preset correspondence between the map level and the ground resolution. Figure 4 As shown, the comparison table of map levels and ground resolutions may include multiple sets of corresponding map levels and ground resolutions, and each set of map levels and ground resolutions has a corresponding relationship. Among them, the map levels in the comparison table include all map levels, and the aforementioned map level range may be a part of all map levels. For example, the map levels in the comparison table include 1-20 map levels, and the aforementioned map level range may include 5-18 map levels.

[0050] Based on the preset correspondence between the map level and the ground resolution, obtaining the target ground resolution corresponding to the target map level includes: searching in the comparison table based on the target map level to obtain the target ground resolution corresponding to the target map level.

[0051] In this way, the target ground resolution corresponding to the target map level can be obtained without further calculation based on the preset correspondence between the target map level, map level and ground resolution, which facilitates the acquisition of ground resolutions corresponding to different map levels.

[0052] Based on any of the above embodiments, step S140 obtains the outline of the map display target area, expands the outline of the map display target area based on the outline expansion algorithm and the physical length corresponding to the target pixel, and obtains the map download area outline to download the map tile data corresponding to the map download area outline, including: obtaining the outline of the map display target area, using the outline expansion algorithm to expand the outline of the map display target area by the physical length corresponding to the target pixel to obtain the map download area outline; determining the map tile number based on the map download area outline and the corresponding map level; obtaining the server access address of the map tile data, splicing the server access address and the map tile number to obtain the download address of the map tile data; downloading the map tile data corresponding to the map download area outline based on the download address.

[0053] By directly expanding the target area outline by the physical length corresponding to the target pixel through the outline expansion algorithm, the map download area outline required to display map information outside the target area can be obtained more accurately when viewing the map at a smaller map level, thereby further reducing the amount of map tile data required to be increased. For example, the outline expansion algorithm can be a Geographic Information System (GIS) algorithm.

[0054] Specifically, a map tile is a map slice file in a pyramid structure hierarchically organized according to a series of map levels within a certain map range. As mentioned above, the map level can also be referred to as a scale level. It can be understood that the outline of the map download area corresponds to a certain map range, and a map tile corresponds to a layer of map slice files of the corresponding map level in the pyramid structure. Therefore, the map tile number can be determined based on the outline of the map download area and the corresponding map level. Among them, each map slice in the map slice file corresponding to the map tile can be uniquely marked by the map level and the row and column number. The row and column number can be the row and column number preset in the map slice file of this layer based on the plane coordinate system, and each map slice has a unique row and column number.

[0055] Exemplarily, the download address of the map tile data may be a Uniform Resource Identifier (URL) for requesting and obtaining the map tile data from a server of the map tile data. The download address of the map tile data may consist of a basic path and required parameter placeholders, wherein the server access address of the map tile data may be used as the basic path, and the map tile number may be used as the required parameter placeholder, so that the download address of the map tile data corresponding to the map download area outline may be obtained by concatenating the server access address and the map tile number, so as to facilitate downloading the map tile data corresponding to the map download area outline.

[0056] Based on any of the above embodiments, after downloading the map tile data corresponding to the map download area outline, the method further includes: repeating the step of obtaining the map download area outline to download the map tile data corresponding to the map area within the map download area outline, obtaining the map download area outline corresponding to each remaining map level in the map level range, and downloading the map tile data corresponding to the corresponding map download area outline respectively. The map level range may be composed of map levels with a relatively high probability of being selected by the user. Exemplarily, the map level range may include map levels 5-18.

[0057] In this way, by pre-downloading the corresponding map tile data for each map level within the map level range, it is possible to provide corresponding map tile data when the map display target area corresponding to different map levels is displayed on the map display interface, thereby avoiding displaying blank areas outside the map display target area, increasing the aesthetics of the map display, and providing a smooth zooming experience when the map display interface responds to user operations to change the map level of the map display target area, thereby improving the user experience.

[0058] It can be understood that each remaining map level in the map level range of the map display target area can be used as the target map level in turn, and the aforementioned steps S110-S140 can be repeated to obtain the map download area outline corresponding to each remaining map level in the map level range of the map display target area, thereby downloading the corresponding map tile data within the corresponding map download area outline respectively.

[0059] The map tile data downloading method provided by the embodiment of the present invention can calculate different map tile downloading area contours for the map display target area and for different map levels, so as to download the corresponding map tile data within the map downloading area contours, thereby ensuring that when the user views the map on the map display interface, the map center is restricted within the map display target area contour, and the map display interface always has complete map information, while reducing the increase in map tile data downloading, and reducing the download time and storage space of the map tile data.

[0060] When the map display target area is a city, when downloading the map tile data corresponding to the map download area outline of the map display target area of ​​map levels 5-18, compared with simply expanding the map tile data download range, the present invention only needs to download about 1% more tiles, which greatly saves tile data download time and tile data storage space.

[0061] In order to specifically illustrate the function of the map tile data downloading method provided by this embodiment, a specific example is provided below.

[0062] The map tile data download method can be applied to the client. The user can generate an input instruction by interacting with the business system that provides the map display interface, and the business system that provides the map display interface can send the user input instruction and the resolution of the map display interface to the client. The input instruction may include a map display target area and a default 5-level map level, and the default 5-level map level is within the map level range.

[0063] For example, the user can enter city B, and the business system that provides the map display interface can generate an input instruction including city B and a level 5 map level, and send the input instruction including city B and the level 5 map level and the resolution of the map display interface 1920×1080 to the client.

[0064] After receiving City B, the map level of level 5, and the resolution of the map display interface of 1920×1080, a comparison table of map level and ground resolution can be obtained, and a search is performed in the comparison table based on the map level of level 5 to obtain the ground resolution of 4891.97 corresponding to the map level of level 5. Then, the coordinates of the center pixel of the map display interface and the pixel coordinates of the outline of the target area displayed on the map can be used to confirm that the center of the map display interface is within the outline of the target area displayed on the map. The physical length corresponding to the target pixel of the map display interface can be obtained by the following formula based on the map level of level 5, the number of long side pixels of 1920 in the resolution of the map display interface, and the ground resolution of 4891.97.

[0065]

[0066] The coordinates of the central pixel point of the map display interface and the pixel point coordinates of the outline of the target area displayed on the map can be used to confirm that the center of the map display interface is on the outline of the target area displayed on the map. The physical length corresponding to the target pixel of the map display interface can be obtained by the following formula based on the target map level, the half value of the number of long side pixels in the resolution of the map display interface and the target ground resolution.

[0067]

[0068] After obtaining the physical length corresponding to the target pixel of the map display interface, the outline of City B can be enlarged by the physical length corresponding to the target pixel of the map display interface through the geographic information system algorithm to obtain the outline of the map download area. Determine the map tile number 5 based on the map download area outline and the 5-level map level. Obtain the server access address of the map tile data, such as http: / / server.com / B-download, concatenate the server access address and the map tile number, and obtain the download address of the map tile data, such as http: / / server.com / B-download / 5. Download the corresponding map tile data within the map download area outline based on the download address.

[0069] After the map is displayed on the map display interface, the user can change the map level by interactively inputting instructions with the business system providing the map display interface. For example, the user can perform an expansion operation on the map display interface to input instructions to change the map level to 8, and then repeat the above steps to download the map tile data corresponding to the map download area outline corresponding to the map level 8 of city B. The map tile data downloading device provided by the present invention is described below, and the map tile data downloading device described below and the map tile data downloading method described above can be referred to each other.

[0070] Figure 5is a schematic diagram of the structure of the map tile data downloading device provided by the present invention, such as Figure 5 As shown, the device includes: a receiving module 210, a ground resolution acquisition module 220, a pixel point physical length acquisition module 230 and a first map tile data downloading module 240.

[0071] The receiving module 210 is used to receive a target map level in a map level range of a map display target area and a resolution of a map display interface.

[0072] The ground resolution acquisition module 220 is used to acquire the target ground resolution corresponding to the target map level based on a preset corresponding relationship between the map level and the ground resolution.

[0073] The pixel point physical length acquisition module 230 is used to acquire the physical length corresponding to the target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution.

[0074] The first map tile data downloading module 240 is used to obtain the outline of the map display target area, expand the outline of the map display target area based on the outline expansion algorithm and the physical length corresponding to the target pixel, and obtain the map download area outline to download the corresponding map tile data within the map download area outline.

[0075] Based on any of the above embodiments, the pixel point physical length acquisition module 230 is specifically used to: obtain the number of long side pixels of the map display interface resolution; confirm that the center of the map display interface is within the outline of the map display target area, and obtain the physical length corresponding to the target pixel of the map display interface according to the target map level, the number of long side pixels and the target ground resolution; wherein the target map level is an exponential coefficient.

[0076] Based on any of the above embodiments, the pixel point physical length acquisition module 230 is further specifically used to: obtain the number of long side pixels of the map display interface resolution, confirm that the center of the map display interface is on the outline of the map display target area, and obtain the physical length corresponding to the target pixel of the map display interface according to the target map level, the half value of the long side pixel number and the target ground resolution; wherein the map level is an exponential coefficient.

[0077] Based on any of the above embodiments, the map tile data downloading device also includes a comparison table acquisition module, which is used to obtain a comparison table of map levels and ground resolutions; wherein the comparison table stores a preset correspondence between the map levels and ground resolutions.

[0078] The ground resolution acquisition module 220 is specifically used to search in the comparison table based on the target map level to obtain the target ground resolution corresponding to the target map level.

[0079] Based on any of the above embodiments, the first map tile data downloading module 240 is specifically used to: obtain the outline of the map display target area, use the outline expansion algorithm to expand the outline of the map display target area by the physical length corresponding to the target pixel, and obtain the map download area outline; determine the map tile number based on the map download area outline and the corresponding map level; obtain the server access address of the map tile data, splice the server access address and the map tile number to obtain the download address of the map tile data; download the corresponding map tile data within the map download area outline based on the download address.

[0080] Based on any of the above embodiments, the map tile data downloading device also includes a second map tile data downloading module, which is used to download the map tile data corresponding to the map download area outline, repeat the step of obtaining the map download area outline to download the map tile data corresponding to the map area within the map download area outline, obtain the map download area outline corresponding to each remaining map level in the map level range, and download the corresponding map tile data within the corresponding map download area outline respectively.

[0081] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6 As shown, the electronic device may include: a processor 310, a communication interface 320, a memory 330 and a communication bus 340, wherein the processor 310, the communication interface 320 and the memory 330 communicate with each other through the communication bus 340. The processor 310 may call the logic instructions in the memory 330 to execute the map tile data download method, which includes: receiving the target map level and the resolution of the map display interface in the map level range of the map display target area; based on the preset corresponding relationship between the map level and the ground resolution, obtaining the target ground resolution corresponding to the target map level; obtaining the physical length corresponding to the target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; obtaining the outline of the map display target area, expanding the outline of the map display target area based on the outline expansion algorithm and the physical length corresponding to the target pixel, and obtaining the map download area outline, so as to download the map tile data corresponding to the map download area outline.

[0082] In addition, the logic instructions in the above-mentioned memory 330 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0083] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the map tile data downloading method provided by the above-mentioned methods, which includes: receiving a target map level and a resolution of a map display interface in a map level range of a map display target area; based on a preset correspondence between the map level and the ground resolution, obtaining a target ground resolution corresponding to the target map level; obtaining a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; obtaining an outline of the map display target area, expanding the outline of the map display target area based on an outline expansion algorithm and the physical length corresponding to the target pixel, and obtaining a map download area outline to download the corresponding map tile data within the map download area outline.

[0084] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the map tile data downloading method provided by the above-mentioned methods, the method comprising: receiving a target map level and a resolution of a map display interface in a map level range of a map display target area; obtaining a target ground resolution corresponding to the target map level based on a preset correspondence between the map level and the ground resolution; obtaining a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; obtaining an outline of the map display target area, expanding the outline of the map display target area based on an outline expansion algorithm and the physical length corresponding to the target pixel, and obtaining an outline of a map download area, so as to download the corresponding map tile data within the outline of the map download area.

[0085] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0086] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for downloading map tile data, characterized in that: include: Receive a target map level in a map level range of a target area for map display and a resolution of a map display interface; Based on a preset correspondence between map level and ground resolution, obtaining a target ground resolution corresponding to the target map level; Acquire a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; The outline of the target area displayed on the map is obtained, and the outline of the target area displayed on the map is expanded based on the outline expansion algorithm and the physical length corresponding to the target pixel to obtain the outline of the map download area, so as to download the map tile data corresponding to the outline of the map download area.

2. The map tile data downloading method according to claim 1, characterized in that: Acquiring a physical length corresponding to a target pixel of the map display interface according to the target map level, the resolution of the map display interface, and the target ground resolution includes: Obtain the number of pixels of the long side of the map display interface resolution; When confirming that the center of the map display interface is within the outline of the map display target area, the physical length corresponding to the target pixel of the map display interface is obtained according to the target map level, the number of pixels on the long side and the target ground resolution; wherein the target map level is an exponential coefficient.

3. The map tile data downloading method according to claim 2, characterized in that: After obtaining the number of pixels of the long side of the map display interface resolution, the method further includes: When confirming that the center of the map display interface is on the outline of the target area displayed on the map, the physical length corresponding to the target pixel of the map display interface is obtained according to the target map level, the half value of the number of pixels on the long side and the target ground resolution; wherein the map level is an exponential coefficient.

4. The map tile data downloading method according to claim 1, characterized in that: Before obtaining the target ground resolution corresponding to the target map level based on the preset corresponding relationship between the map level and the ground resolution, the method further includes: Obtaining a comparison table of map levels and ground resolutions; wherein the comparison table stores a preset correspondence between the map levels and ground resolutions; Based on the preset corresponding relationship between the map level and the ground resolution, obtaining the target ground resolution corresponding to the target map level includes: The comparison table is searched based on the target map level to obtain the target ground resolution corresponding to the target map level.

5. The map tile data downloading method according to claim 1, characterized in that: Acquiring the outline of the target area displayed on the map, expanding the outline of the target area displayed on the map based on an outline expansion algorithm and a physical length corresponding to the target pixel, obtaining a map download area outline, and downloading map tile data corresponding to the map download area outline, including: Acquire the outline of the target area displayed on the map, and use the outline expansion algorithm to expand the outline of the target area displayed on the map by the physical length corresponding to the target pixel to obtain the outline of the map download area; Determining a map tile number based on the map download area outline and the corresponding map level; Obtaining a server access address of the map tile data, concatenating the server access address and the map tile number, and obtaining a download address of the map tile data; The map tile data corresponding to the map download area outline is downloaded based on the download address.

6. The map tile data downloading method according to claim 1, characterized in that: After downloading the map tile data corresponding to the map download area outline, the method further includes: Repeat the steps of obtaining a map download area outline to download map tile data corresponding to the map area within the map download area outline, obtain a map download area outline corresponding to each remaining map level in the map level range, and download the map tile data corresponding to the corresponding map download area outlines respectively.

7. A map tile data downloading device, characterized in that: include: A receiving module, used for receiving a target map level in a map level range of a target area of ​​map display and a resolution of a map display interface; A ground resolution acquisition module, used for acquiring a target ground resolution corresponding to the target map level based on a preset correspondence between the map level and the ground resolution; A pixel point physical length acquisition module, used to acquire the physical length corresponding to the target pixel of the map display interface according to the target map level, the resolution of the map display interface and the target ground resolution; The first map tile data downloading module is used to obtain the outline of the map display target area, expand the outline of the map display target area based on the outline expansion algorithm and the physical length corresponding to the target pixel, and obtain the map download area outline to download the corresponding map tile data within the map download area outline.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the map tile data downloading method as described in any one of claims 1 to 6 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the map tile data downloading method as claimed in any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the map tile data downloading method as claimed in any one of claims 1 to 6 is implemented.

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