Side line drawing collinear processing method for segmental arc decomposition of geographic entity

Abstract

The invention relates to the technical field of map making, in particular to a geography entity segmental arc decomposition side line drawing collinear processing method. According to the method for judging and selecting the priorities of the collinear arc segments under the constraint of the entity data topological structure, the topological structure containing rich semantic information is established, the independent topological arc segments serve as selection units to be selected, collinear arc segment modes are distinguished, and corresponding priority judgment and selection are conducted, so that the priority of the collinear arc segments is judged and selected. And finally, reconstructing the discrete arc section into a geographic entity according to semantic information. Through inspection of an actual topographic map, the method shows high efficiency in processing of collinear arc segments in side line drawing, the collinear processing efficiency is improved, meanwhile, high-quality presentation of the map is ensured, and therefore reliable technical support is provided for accurate drawing of the topographic map.

Description

Technical Field

[0001] The present invention relates to the technical field of cartography, and particularly to a collinear processing method for boundary line cartography in the arc segmentation and decomposition of geographical entities. Background Art

[0002] Boundary line cartography, as an important link in the new basic surveying and mapping environment, undertakes the key task of converting entity data into topographic maps. Its core lies in converting entity surface data into diverse cartographic boundary lines. In this process, if the shared boundaries between different entities independently generate topographic map feature data, it will inevitably cause spatial conflicts between linear features. Such conflicts not only damage the overall effect of the mapped figure in the subsequent symbolization stage of the map but may also pose obstacles to the correct understanding of spatial information. Therefore, it is necessary to perform collinear processing on the shared boundaries of feature data to maintain the accuracy and readability of the map.

[0003] The prior art processes feature data through shifting. Although it effectively prevents conflicts between data, it does so at the cost of sacrificing the spatial accuracy of the data and the key topological relationships between features. Topological relationships, as the core information depicting the relative positions and connection states between topographic map features, play a decisive role in the accuracy of data analysis and cartography. The absence of these key relationships not only limits the application potential of the data in complex spatial analysis but may also lead to biases in the decision-making process because accurate and comprehensive spatial understanding is crucial for decision-making.

[0004] Therefore, seeking a collinear processing method for boundary line cartography that can not only ensure no conflicts between data but also accurately maintain spatial positions and topological relationships has become the key to improving the data processing and analysis capabilities of topographic maps. Summary of the Invention

[0005] Aiming at the above deficiencies in the prior art, the purpose of the present invention is to provide a collinear processing method for boundary line cartography in the arc segmentation and decomposition of geographical entities that can not only ensure no conflicts between data but also accurately maintain spatial positions and topological relationships.

[0006] To achieve the above invention purpose, the technical solution adopted by the present invention is as follows:

[0007] Provide a collinear processing method for boundary line cartography in the arc segmentation and decomposition of geographical entities, which includes the following steps:

[0008] According to geographical entities, construct a topological structure rich in semantic information, use independent topological arcs as the selected basic units, distinguish different modes of collinear arcs, and accordingly perform priority judgment and selection; based on semantic information, re-integrate the discretized arcs into complete geographical entities.

[0009] Further, the specific steps are as follows:

[0010] Step 1: Construct the topological structure; establish the topological structure for the simplified geographical entity arcs; this process involves converting arcs into polygons; when generating polygons, the definition of polygons must be followed, that is, ensuring that three or more line segments are connected end to end to form a closed planar figure;

[0011] Step 2: Traverse and assign semantic information; traverse the constructed topological polygons and check which arcs each polygon consists of; during this process, carefully identify the semantic information of each arc; if it is found that the arcs forming the polygon have the same semantic information, then inherit this semantic information to the entire polygon to ensure that the attributes of the polygon are consistent with its components;

[0012] Step 3: Transmit semantic information to newly added arcs; continue to traverse the polygon set, and for the polygons composed of newly added arcs, it is necessary to transmit the semantic information of the polygon to these newly added arcs;

[0013] Step 4: Completion of entity reconstruction; when all polygons have gone through the above processing steps, the entity reconstruction process is declared complete.

[0014] Furthermore, the collinear edge processing is divided into two strategies: one is to directly remove the collinear arcs, and the other is to make a judgment based on the priority table within and between entity classes and retain the collinear arcs with higher priority; in the following situations, different processing methods are adopted:

[0015] When the shared arc is not an essential element for drawing the topographic map and its retention will damage the integrity of the mapping data, thereby affecting the mapping effect and interpretation result, directly delete the collinear arcs; on the contrary, when the shared arc is crucial for the accurate drawing of the topographic map and the topological relationship remains good, although there may be boundary overlaps and redundancies after mapping, but the integrity of the data is not affected, at this time, retain the collinear arcs with higher priority and remove the arcs with lower priority.

[0016] Furthermore, except for the cases where the intersection surface and the road surface are collinear and the cases where the same elements within the water system surface class are collinear, for other collinear situations occurring in the edge mapping, the principle of retaining the collinear arcs with higher priority is followed, that is, retaining the collinear arcs with higher priority and deleting the collinear arcs with lower priority.

[0017] Furthermore, the disappearance mode of collinear arcs is as follows:

[0018] Step 1: Screen relevant arcs; collect all sets of arcs to be judged and traverse each arc; during this process, identify and judge whether the current arc contains entity coding information; if it is confirmed to contain, add this arc to the queue V_Road for further processing; if not, continue to traverse to the next arc;

[0019] Step 2: Process the arc segment queue; Extract all relevant arc segment data from the queue V_Road; If V_Road is empty, it indicates that there are no arc segments to be processed, and the process terminates at this time; Otherwise, take an arc segment from the tail of the queue as the current processing object, make subsequent judgments, and remove the arc segment from the queue at the same time;

[0020] Step 3: Identify shared and non-shared arc segments; For the currently processed arc segment, check its entity attribute information table; If the information table contains multiple entity codes, mark the arc segment as a shared arc segment and add it to the queue M_Road for storage for subsequent processing; If the information table contains only a single entity code, the arc segment is a non-shared arc segment and does not require further storage or processing;

[0021] Step 4: Delete and synchronize shared arc segments; Delete all arc segment data marked as shared from the queue M_Road. During the deletion operation, synchronously update the relevant point-line topological relationships to ensure the integrity and topological consistency of the map data.

[0022] Furthermore, the priority mode for collinear arc segments is as follows:

[0023] Step 1: Initialize the priority configuration; Load the intra-class and inter-class priority tables of entity codes; This table will be used as the basis for subsequent judgments and processing to ensure that the priorities of each entity feature are correctly reflected during the collinear processing;

[0024] Step 2: Construct the queue of arc segments to be processed; Collect all arc segments to be judged and store them in the set V in the form of a queue; This set will be used as the input for subsequent processing and provide a data basis for collinear judgment;

[0025] Step 3: Identify shared arc segments; Traverse each arc segment in the set V and query its corresponding entity attribute information table; If the entity attribute information table of an arc segment contains multiple entity codes, determine that the arc segment is a shared arc segment and add it to the queue M for storage; If the information table contains only a single entity code, the arc segment is a non-shared arc segment and does not require further processing;

[0026] Step 4: Process the queue of shared arc segments; Extract all shared arc segment data from the queue M. If M is empty, end the processing; Otherwise, take an arc segment from the tail of the queue as the current processing object, make subsequent judgments, and remove the arc segment from the queue at the same time;

[0027] Step 5: Sort the entity code priorities; According to the priority table loaded in Step 1, sort the entity codes in the entity attribute information table of the current arc segment. The sorting is based on the importance of the entity codes, arranged from high to low, to ensure that the entity codes with higher priorities are retained during the collinear processing;

[0028] Step 6: Entity coding screening and retention; After sorting, retain the entity coding information with the highest priority in the current arc segment entity attribute information table, and remove other entity coding information with lower priority.

[0029] The beneficial effects of the present invention are as follows:

[0030] By constructing a topological structure rich in semantic information, the present invention takes independent topological arc segments as the basic selection units, distinguishes different patterns of collinear arc segments, and makes priority judgments and selections accordingly. Finally, based on semantic information, the discretized arc segments are re-integrated into complete geographical entities. This technical means effectively improves the processing efficiency of collinear arc segments in edge line mapping and ensures the high-quality presentation of maps. Description of the Drawings

[0031] Figure 1 Schematic diagram of road surface connection in the embodiment;

[0032] Figure 2 Schematic diagram of water system surface connection in the embodiment;

[0033] Figure 3 Schematic diagram of different types of collinear priorities in the embodiment;

[0034] Figure 4 Schematic diagram of road collinear processing result in the embodiment;

[0035] Figure 5 Schematic diagram of water system collinear processing result in the embodiment;

[0036] Figure 6 Schematic diagram of residential area collinear processing result in the embodiment;

[0037] Figure 7 Schematic diagram of traffic-water system collinear processing result in the embodiment;

[0038] Figure 8 Schematic diagram of residential area-water system collinear processing result in the embodiment;

[0039] Figure 9 Schematic diagram of road-residential area collinear processing result in the embodiment;

[0040] Figure 10 Schematic diagram of traffic-residential area-vegetation collinear processing result in the embodiment;

[0041] Figure 11 Schematic diagram of traffic-residential area-water system collinear processing result in the embodiment;

[0042] Figure 12 Schematic diagram of traffic-residential area-water system-vegetation collinear processing result in the embodiment. Detailed implementation manners

[0043] The following describes the detailed implementation manners of the present invention to facilitate those skilled in the art of the present technology to understand the present invention. However, it should be clear that the present invention is not limited to the scope of the detailed implementation manners. For those of ordinary skill in the art of the present technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions created using the concept of the present invention are within the scope of protection.

[0044] Embodiment

[0045] Classification and method for collinear processing

[0046] The collinear processing of the side lines is mainly divided into two strategies: one is to directly remove the collinear arc segments, and the other is to make a judgment based on the priority table within and between entity classes and retain the collinear arc segments with higher priority. In the following situations, different processing methods should be adopted:

[0047] When the shared arc segment is not an essential element for drawing the topographic map and its retention will damage the integrity of the mapping data, thereby affecting the mapping effect and interpretation result, the collinear arc segment should be directly deleted. On the contrary, when the shared arc segment is crucial for the accurate drawing of the topographic map and the topological relationship remains good, although there may be boundary overlaps and redundancies after mapping, but the integrity of the data is not affected, at this time, the collinear arc segment with higher priority should be retained, and the arc segment with lower priority should be removed.

[0048] Specifically, the following situations are applicable to the processing method of directly deleting the collinear arc segment: ① The intersection surface and the road surface are collinear: In the entity data, the road surface and the corresponding intersection surface are represented separately, but in the topographic map, the intersection surface and the road surface are not distinguished; ② The same elements within the water system class are collinear: In the entity data, the main trunk and tributaries of the water system surface are distinguished, but in fact they belong to the same river. In these two situations, the principle of directly deleting the collinear arc segment should be followed.

[0049] Except for the situation where the intersection surface and the road surface are collinear, and the situation where the same elements within the water system surface class are collinear, for other collinear situations that occur in the side line mapping, the principle of retaining the collinear arc segment with higher priority should be followed, that is, retaining the collinear arc segment with higher priority and deleting the collinear arc segment with lower priority.

[0050] (1) Collinear arc segment extinction mode

[0051] 1) Road intersection connection ( Figure 1 )

[0052] Step 1: Screen the arc segments related to intersections. First, collect all the sets of arc segments to be judged and traverse each arc segment. During this process, identify and judge whether the current arc segment contains the entity intersection surface coding information. If it is confirmed to contain, add this arc segment to the queue V_Road for further processing; if it does not contain, continue to traverse to the next arc segment.

[0053] Step 2: Process the queue of intersection arc segments. Next, extract all the arc segment data related to intersections from the queue V_Road. If V_Road is empty, it means there are no intersection arc segments to process, and the process terminates at this time; otherwise, take an arc segment from the end of the queue as the current processing object, make subsequent judgments, and remove this arc segment from the queue.

[0054] Step 3: Identify shared and non-shared intersection arc segments. For the currently processed arc segment, check its entity attribute information table. If the information table contains multiple entity codes, mark this arc segment as a shared arc segment and add it to the queue M_Road for storage for subsequent processing. If the information table contains only a single entity code, this arc segment is a non-shared arc segment and does not need further storage or processing.

[0055] Step 4: Delete and synchronize the shared intersection arc segments. Finally, delete all the marked shared intersection arc segment data from the queue M_Road. During the deletion operation, it is necessary to synchronously update the relevant point-line topological relationships to ensure the integrity and topological consistency of the map data.

[0056] In the entire processing flow of opening up road intersections, the accurate identification and operation of arc segments are crucial. In Step 1, for the screening of intersection arc segments, the directionality of the arc segments, the shape of the intersections, and the relationship with other features need to be considered. In Step 2, when processing the queue of intersection arc segments, attention should be paid to the efficiency of queue operations. In Step 3, for the identification of shared and non-shared intersection arc segments, the accuracy and integrity of the entity coding information should be ensured. Finally, in Step 4, when deleting the shared arc segments and updating the topological relationships, detailed operation logs should be recorded to facilitate subsequent data review and problem tracking. Through these meticulous steps, the accurate expression of road intersections on the map can be ensured, improving the overall quality and user experience of the map.

[0057] 2) Water system surface opening ([ Figure 2 ) :

[0058] Step 1: Screen the arc segments related to water systems. First, collect all the sets of arc segments to be judged and traverse each arc segment. During this process, identify and judge whether the current arc segment belongs to the entity water system surface coding information. If it is confirmed to belong, add this arc segment to the queue V_River for further processing; if it does not belong, continue to traverse to the next arc segment.

[0059] Step 2: Process the water system arc segment queue. Next, extract all the arc segment data related to the water system from the queue V_River. If V_River is empty, it indicates that there are no water system arc segments to be processed, and the process terminates at this time; otherwise, take an arc segment from the tail of the queue as the current processing object, make subsequent judgments, and remove the arc segment from the queue.

[0060] Step 3: Identify shared and non-shared water system arc segments. For the currently processed arc segment, check its entity attribute information table. If the information table contains two identical within-water-system-entity class codes, mark the arc segment as a shared arc segment and add it to the queue M_River for storage for subsequent processing. If the information table contains two different water system entity codes or only a single entity code, the arc segment is a non-shared arc segment and does not require further storage or processing.

[0061] Step 4: Delete and synchronize water system shared arc segments. Finally, delete all the marked shared water system arc segment data from the queue M_River. During the deletion operation, the relevant point-line topological relationships need to be synchronized and updated to ensure the integrity and topological consistency of the map data.

[0062] In the processing flow of water system surface connection, accurately identifying and operating on arc segments is the key to ensuring the continuity and accuracy of the water system. In Step 1, when screening water system-related arc segments, the subordination relationship between the arc segments and the water system surface, as well as the position and role of the arc segments in the water system network, should be considered. In Step 2, when processing the water system arc segment queue, the efficiency of queue operations and the accuracy of data should be ensured. In Step 3, for the identification of shared and non-shared water system arc segments, special attention should be paid to the matching rules of entity codes to avoid misjudgment. In Step 4, when deleting shared arc segments and updating topological relationships, the consistency of operations and the stability of data should be ensured. In addition, detailed operation logs should be recorded throughout the process for subsequent data review and problem troubleshooting. Through these refined steps, the expression of the water system on the map can be optimized, and the overall quality of the map and the user experience can be improved.

[0063] (2) Collinear arc segment priority mode ( Figure 3 )

[0064] Within-class collinear processing: The phenomenon of within-class collinearity refers to the situation where when multiple collinear entity elements belong to the same entity major class, such as residential areas, roads, water systems, etc., on the arc segments shared by these entities in the collinear part, their entity attribute information tables will record multiple relevant entity codes. In this case, the core of collinear processing lies in identifying and processing the overlapping of entities within the same category to ensure that the integrity of the entities can be maintained in the map expression while avoiding information redundancy and unnecessary confusion.

[0065] Inter-class collinear processing: Relatively speaking, inter-class collinearity involves the collinear relationship between different major entity categories, such as the collinearity between residential areas and roads, water systems and other features. In these cases, the collinear entities belong to different categories respectively, and the shared arc segments of their collinear parts will also contain multiple entity codes in the entity attribute information table. The key to inter-class collinear processing lies in coordinating the spatial relationships between different entity categories, ensuring that their respective features are clearly expressed on the map while maintaining their topological consistency.

[0066] When dealing with intra-class collinearity, special attention needs to be paid to the characteristics of entity features and their display requirements on the map. For example, for the collinearity within the water system class, it may be necessary to distinguish between main river channels and tributaries. Even in the collinear area, this distinction should be maintained through the entity codes in the attribute information table to ensure the accuracy and readability of the map. In the case of inter-class collinearity, the processing strategy needs to be more meticulous because different major entity categories may have different requirements in terms of map symbols, annotations, and displays. For example, when a road and a residential area are collinear, special processing may be required for these shared arc segments to ensure that the continuity of the road and the integrity of the residential area are both reflected. This may involve fine operations on the entity attribute information table and appropriate symbolization and annotation adjustments for the collinear arc segments. In short, whether it is intra-class collinearity or inter-class collinearity, the goal of collinear processing is to improve the quality of the map, ensure the accurate transmission of information, and at the same time optimize the visual effect and spatial cognition of the map. Through the precise management of the entity attribute information table and the intelligent processing of collinear arc segments, this goal can be achieved, providing users with high-quality map products. The specific process is as follows:

[0067] Step 1: Initialize the priority configuration. First, load the intra-class and inter-class priority tables of entity codes. This table will be used as the basis for subsequent judgments and processing to ensure that the priorities of each entity feature are correctly reflected during the collinear processing.

[0068] Step 2: Construct the queue of arcs to be processed. Then, collect all the arcs to be judged and store them in a queue form in the set V. This set will serve as the input for subsequent processing, providing the data basis for collinear judgment.

[0069] Step 3: Identify shared arc segments. Traverse each arc segment in the set V and query its corresponding entity attribute information table. If the entity attribute information table of an arc segment contains multiple entity codes, then this arc segment is determined to be a shared arc segment and added to the queue M for storage. If the information table contains only a single entity code, then this arc segment is a non-shared arc segment and does not require further processing.

[0070] Step 4: Process the shared arc segment queue. Extract all shared arc segment data from the queue M. If M is empty, end the processing; otherwise, take an arc segment from the tail of the queue as the current processing object, perform subsequent judgment, and remove the arc segment from the queue.

[0071] Step 5: Entity code priority sorting. Sort the entity codes in the entity attribute information table of the current arc segment according to the priority table loaded in step 1. The sorting is based on the importance of the entity code, from high to low, to ensure that the entity codes with higher priority are retained in the collinear processing.

[0072] Step 6: Entity code screening and retention. After sorting, retain the entity code information with the highest priority in the current arc entity attribute information table, and remove other entity code information with lower priority. This step ensures that only the most important entity information is retained in the processing of collinear arcs, thereby maintaining the accuracy and clarity of the map data.

[0073] Throughout the entire processing flow, careful operations are required to ensure the integrity and accuracy of the data for the identification of each shared arc and the sorting of entity codes. For example, in step three, when querying the entity attribute information table, the integrity and uniqueness of the entity code need to be considered to avoid errors in collinearity judgment. In the sorting process of step five, the relationship between different entity types and their specific requirements in map expression need to be considered. Finally, in step six, for the operation of removing entity codes, the corresponding processing log should be recorded to facilitate subsequent data review and problem tracking. Through these meticulous steps, the efficiency of collinearity processing and the high quality of map data can be ensured.

[0074] B. Entity Reconstruction under Semantic Constraints

[0075] In the process of edge mapping, the collinear relationship is processed according to the collinear mode identified and classified above. The core goal of this application is to follow the basic principles of collinear processing, ensure that the processing results are clearly distinguishable at the target scale, maintain the basic stability of the original morphological features, and ensure that no topological errors are introduced.

[0076] To achieve this goal, the strategy of topological fragmentation and arc segment local processing is adopted to optimize the edge. After the collinearity processing of all arc segments is completed, the processed arc segments must be reorganized to maintain the consistency of the data structure before and after processing. Thanks to the original semantic information of each arc segment being maintained during the entire processing process, this application proposes an entity reconstruction method based on semantic constraints to accurately restore the arc segments and ensure the integrity and accuracy of the geographic entities.

[0077] This method not only restores the spatial structure of geographic entities by utilizing the original semantic information of arcs, but also strengthens the logical relationship of data, thereby improving the overall quality and usability of the map. During the reorganization process, the position and connection relationship of each arc are carefully verified to ensure that the map after collinear processing not only maintains its beauty, but also meets the accuracy of geographic information and the correctness of topological relationships. This processing strategy not only optimizes the visual effect of the map, but also provides a solid data foundation for subsequent spatial analysis and decision support. The specific process is as follows:

[0078] Step 1: Construct the topological structure. First, the simplified arc segments are topologically constructed. This process involves converting the arc segments into polygons. When generating polygons, the definition of polygons must be followed, that is, to ensure that three or more line segments are connected end to end to form a closed plane figure. This step is the basis for ensuring the accuracy of the spatial relationship of geographic entities.

[0079] Step 2: Semantic information traversal and assignment. Next, traverse the constructed topological polygons and check which arcs each polygon is composed of. In this process, carefully identify the semantic information of each arc. If it is found that the arcs that make up the polygon have the same semantic information, then inherit the semantic information to the entire polygon to ensure that the attributes of the polygon are consistent with its components.

[0080] Step 3: Transfer semantic information to newly added arcs. Continue to traverse the polygon set. For polygons composed of newly added arcs, the semantic information of the polygons needs to be transferred to these newly added arcs. This step ensures that during the entity reconstruction process, all arcs can inherit and maintain the semantic attributes of the polygons to which they belong, thereby maintaining the integrity and consistency of the data.

[0081] Step 4: Entity reconstruction is complete. Finally, when all polygons have gone through the above processing steps, the entity reconstruction process is completed. This step ensures that the spatial relationships and semantic information of all arcs and polygons are accurately restored and updated, thereby achieving accurate reconstruction of geographic entities. Through this series of sophisticated operations, we not only restored the spatial structure of geographic entities, but also enhanced the logic and usability of the data, providing reliable data support for subsequent spatial analysis and decision-making.

[0082] Figures 4 - 12 This is part of the results of the collinear topology processing performed by the method of the present invention. Figure 4 , Figure 5 , Figure 6 As shown in the figure, it is the result of processing the collinear parts of similar elements of different levels of roads, water systems, and residential entities in a certain experiment. According to the priority of the elements, the collinear data is reasonably retained to make the map result clear. Figure 7 , Figure 8 ,Figure 9 , Figure 10 , Figure 11 , Figure 12 are the results of collinear processing for different types of geographical entities. The collinearity of edges in edge mapping is a key point in the process of topographic map mapping. It is necessary to take into account the spatial, topological, and semantic features of entity data. The method for judging and selecting the priority of collinear arc segments under the constraint of the topological structure of entity data proposed in this application establishes a topological structure containing rich semantic information, selects independent topological arc segments as the selection units, distinguishes the collinear arc segment patterns and makes corresponding priority judgments and selections, and finally reconstructs the discrete arc segments into geographical entities according to the semantic information. After being tested by actual topographic maps, this method shows high efficiency in the processing of collinear arc segments in edge mapping, not only improving the efficiency of collinear processing, but also ensuring the high-quality presentation of the map, thus providing reliable technical support for the precise mapping of topographic maps.

[0083] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A method for processing collinearity in edge mapping by decomposing geographic entities into arc segments, characterized in that: The following steps are involved: Based on geographic entities, a topological structure rich in semantic information is constructed. Independent topological arcs are used as the basic units for selection. Different patterns of collinear arcs are distinguished, and priority judgment and selection are made accordingly. Based on semantic information, the discrete arcs are reintegrated into complete geographic entities.

2. The method for processing collinearity of edge mapping by decomposing geographic entities into arc segments according to claim 1, characterized in that: The specific steps are as follows: Step 1: Construct the topological structure; construct the topological structure of the simplified geographic entity arc segment; this process involves converting the arc segment into a polygon; when generating a polygon, the definition of a polygon must be followed, that is, to ensure that three or more line segments are connected end to end to form a closed plane figure; Step 2: Semantic information traversal and assignment: traverse the constructed topological polygons and check which arcs each polygon is composed of; in this process, carefully identify the semantic information of each arc; If it is found that the arcs that make up a polygon have the same semantic information, the semantic information is inherited to the entire polygon to ensure that the attributes of the polygon are consistent with its components; Step 3: passing semantic information to the newly added arcs; continue to traverse the polygon set, and for polygons formed by the newly added arcs, the semantic information of the polygons needs to be passed to these newly added arcs; Step 4: Entity reconstruction is completed; when all polygons have gone through the above processing steps, the entity reconstruction process is declared complete.

3. The method for processing collinearity in edge mapping by decomposing geographic entities into arc segments according to claim 1 or 2, characterized in that: There are two strategies for edge collinearity processing: one is to directly remove collinear arc segments, and the other is to make judgments based on the priority tables within and between entity classes and retain collinear arc segments with higher priorities; Different approaches are taken in the following situations: When shared arcs are not necessary elements for drawing topographic maps, and their retention will damage the integrity of the mapping data, thus affecting the mapping effect and interpretation results, the collinear arcs are directly deleted; on the contrary, when shared arcs are crucial to the accurate drawing of topographic maps and the topological relationship is well maintained, although boundary overlap and redundancy may occur after mapping, the integrity of the data is not affected. At this time, the collinear arcs with higher priority are retained, and the arcs with lower priority are removed.

4. The method for processing collinearity of edge mapping by decomposing geographic entities into arc segments according to claim 3, characterized in that: Except for the case where the intersection surface and the road surface are collinear, and the case where the same elements within the water system surface class are collinear, other collinear situations that appear in edge mapping all follow the principle of retaining collinear arcs with higher priority, that is, retaining collinear arcs with higher priority and deleting collinear arcs with lower priority.

5. The method for processing collinearity in edge mapping of arc segment decomposition of geographic entities according to claim 4, characterized in that: The loss mode of collinear arc segments is: Step 1: Filter relevant arcs; collect all arcs to be judged and traverse each arc; in this process, identify and judge whether the current arc contains entity coding information; if it is confirmed to contain, add the arc to the queue V_Road for further processing; if not, continue to traverse to the next arc; Step 2: Process the arc queue; extract all relevant arc data from the queue V_Road; if V_Road is empty, it means that there is no arc to be processed, and the process terminates; otherwise, take an arc from the end of the queue as the current processing object, perform subsequent judgment, and remove the arc from the queue; Step 3: Identify shared and non-shared arcs; for the arc currently being processed, check its entity attribute information table; if the information table contains multiple entity codes, mark the arc as a shared arc and add it to the queue M_Road for storage for subsequent processing; if the information table contains only a single entity code, the arc is a non-shared arc and does not need to be further stored or processed; Step 4: Delete and synchronize shared arcs; delete all arc data marked as shared from the queue M_Road. While deleting, update the related point-line topological relationships synchronously to ensure the integrity and topological consistency of the map data.

6. The method for processing collinearity in edge mapping by decomposing geographic entities into arc segments according to claim 4, characterized in that: The priority mode of collinear arcs is: Step 1: Initialize the priority configuration; load the intra-class and inter-class priority table of the entity code; this table will serve as the basis for subsequent judgment and processing to ensure that the priority of each entity element is correctly reflected during the collinear processing; Step 2: Construct a queue of arcs to be processed; collect all arcs to be judged and store them in a set V in the form of a queue; this set will serve as input for subsequent processing and provide a data basis for collinearity judgment; Step 3: Identify shared arcs; traverse each arc in the set V and query its corresponding entity attribute information table; if the entity attribute information table of an arc contains multiple entity codes, the arc is determined to be a shared arc and added to the queue M for storage; if the information table contains only a single entity code, the arc is a non-shared arc and no further processing is required; Step 4: Process the shared arc segment queue; extract all shared arc segment data from the queue M. If M is empty, the processing is terminated; otherwise, an arc segment is taken from the tail of the queue as the current processing object, and subsequent judgment is performed, and the arc segment is removed from the queue; Step 5: Entity code priority sorting: According to the priority table loaded in step 1, the entity codes in the entity attribute information table of the current arc segment are sorted. The sorting basis is the importance of the entity code, and the entity codes are arranged from high to low to ensure that the entity codes with higher priority are retained in the collinear processing; Step 6: Entity code screening and retention; After the sorting is completed, the entity coding information with the highest priority in the current arc entity attribute information table is retained, and other entity coding information with lower priority is removed.

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