Method for intelligent marking of mechanical and electrical pipelines based on BIM three-dimensional model drawing

Abstract

The present application relates to the technical field of BIM electromechanical drawing, in particular to a method for intelligent marking of electromechanical pipelines based on BIM three-dimensional model drawing, which obtains the BIM view corresponding to the BIM three-dimensional model formed based on three-dimensional modeling, projects the electromechanical pipeline primitives to the two-dimensional view plane to obtain the projected pipeline segment, forms the scanning state along two mutually perpendicular scanning directions, combines the other scanning direction to exclude the arrangement order change of the continuously existing electromechanical pipeline primitives, and determines the pipeline combination state change boundary according to the change of the pipeline primitive composition or grouping relationship; accordingly, the stable marking section is determined, the marking group is formed, and the group-level marking is generated; and the marking text and the lead are adjusted within the position adjustment range and then output to the BIM view. The present application can accurately identify the pipeline combination change, reduce repeated marking and marking conflicts, and improve the BIM drawing efficiency and drawing quality.

Description

Technical Field

[0001] This invention relates to the field of BIM MEP drawing technology, specifically a method for intelligent annotation of MEP pipelines based on BIM 3D model drawing. Background Technology

[0002] In the BIM-based MEP (Mechanical, Electrical, and Plumbing) design process, after creating a 3D MEP model through 3D modeling, it is necessary to generate 2D plan or sectional views based on the model to guide construction. The diameter or cross-sectional dimensions, system type, and elevation of MEP pipelines such as ducts, water pipes, and cable trays in the drawings must be labeled. Current labeling methods mainly rely on designers manually selecting MEP pipeline elements, inputting label text, and adjusting leader line positions. This process is inefficient and prone to problems such as missed labels, incorrect labels, duplicate labels, overlapping label text, and intersecting leader lines. Furthermore, the labeling results are easily influenced by the designer's operating habits.

[0003] Existing CAD or BIM-assisted annotation tools typically focus on simplifying single annotation operations. While they can extract MEP (Mechanical, Electrical, and Plumbing) elements or group them according to geometric distance, they struggle to accurately distinguish between changes in the arrangement order of continuous pipelines and actual pipeline combinations in complex situations such as pipeline intersections, entry / exit points, and changes in grouping relationships. Furthermore, current technologies lack mechanisms to determine stable grouping ranges based on pipeline combination states and to limit the adjustment position of group-level annotations, making it difficult to balance annotation accuracy, annotation quantity, and drawing layout quality. Therefore, a method is needed that can automatically identify pipeline combination changes from BIM views, form stable annotation groups, and perform annotation avoidance adjustments. Summary of the Invention

[0004] This invention provides a method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing, which automates annotation grouping, generation and layout adjustment.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The present invention provides a method for intelligent annotation of electromechanical pipelines based on BIM 3D model generation, comprising: S100: Obtain the BIM view, extract the electromechanical pipeline elements and their geometric and attribute information from the BIM view, and project the electromechanical pipeline elements onto the two-dimensional view plane to obtain the projected pipeline segment; S200: Using scan lines, scan along two mutually perpendicular directions in the two-dimensional view plane respectively, and form a scan state arranged along the corresponding scan direction based on the intersection of the scan lines and the projection pipeline segment, the corresponding electromechanical pipeline elements and their arrangement order; S300: Compare adjacent scanning states, combine the scanning states in another scanning direction to eliminate the influence of changes in the arrangement order of continuously existing electromechanical pipeline elements on boundary determination, and determine the pipeline combination state change boundary based on changes in the composition of the electromechanical pipeline elements or changes in the grouping relationship between the projected pipeline segments. S400: Using the boundary of the pipeline combination state change as the boundary, determine a stable annotation section along the extension direction of the projected pipeline segment, form an annotation group according to the common occurrence relationship, directional relationship and spacing relationship of the projected pipeline segment in the stable annotation section, and generate group-level annotations according to the attribute information corresponding to the annotation group; S500: Determine the position adjustment range of the group-level annotation based on both ends of the stable annotation section along the extension direction of the projection pipeline segment, adjust the position of the annotation text and leader of the group-level annotation within the position adjustment range, and output the adjusted group-level annotation to the BIM view.

[0006] As a preferred embodiment of the present invention, in S100, the specific steps of projecting the electromechanical pipeline elements onto the two-dimensional view plane include: The overall three-dimensional bounding box of all the electromechanical pipeline elements is determined based on the geometric information of the electromechanical pipeline elements; The overall three-dimensional bounding box is projected onto the two-dimensional view plane to obtain the scanning processing range; The geometric information of the electromechanical pipeline elements is projected onto the two-dimensional view plane to obtain the projected pipeline segment located within the scanning processing range.

[0007] As a preferred embodiment of the present invention, in S200, the specific steps for forming the scanning states arranged along the corresponding scanning direction include: For each scanning direction, within the scanning processing range, scanning lines that are parallel to each other and perpendicular to the corresponding scanning direction are set at a preset scanning interval; Determine the intersection point of the scan line and the projection pipeline segment, and arrange the corresponding electromechanical pipeline elements according to the position of the intersection point on the corresponding scan line; Record the element identifiers, intersection positions, and arrangement order of the electromechanical pipeline elements to form the scanning state corresponding to each scan line, and arrange the scanning states according to the arrangement order of the scan lines along the corresponding scanning direction.

[0008] As a preferred embodiment of the present invention, in S300, the specific steps of comparing adjacent scan states include: The composition and arrangement order of electromechanical pipeline elements in adjacent scanning states are compared to determine the directional difference and centerline spacing between commonly appearing projection pipeline segments. The grouping relationship is determined based on the comparison results of the directional difference with the preset directional deviation and the centerline spacing with the preset grouping distance. The adjacent scan lines where the composition, arrangement order, or grouping relationship of the electromechanical pipeline elements changes are identified as candidate state change intervals. Within the candidate state change range, a thinner scan line parallel to the adjacent scan line is added, and the scan state corresponding to the thinner scan line is formed. By comparing the scan states of the refined scan line with those of its adjacent scan lines, the adjacent scan lines that still have changes in the composition, arrangement order or grouping relationship of the electromechanical pipeline elements are re-determined as candidate state change intervals. Within the newly determined candidate state change interval, the refined scan lines are continued to be added until the width of the candidate state change interval is no greater than the preset boundary width.

[0009] As a preferred embodiment of the present invention, in S300, the specific steps for determining the boundary of pipeline combination state change include: The electromechanical pipeline elements on both sides of the candidate state change interval are matched according to the element identifier, and the continuity of the matched electromechanical pipeline elements in the candidate state change interval is determined according to the scanning state in another scanning direction. When the electromechanical pipeline elements on both sides of the candidate state change interval are the same and the matching electromechanical pipeline elements exist continuously, the change in the arrangement order within the candidate state change interval is not used as the basis for determining the boundary of the pipeline combination state change. When the electromechanical pipeline element appears continuously on one side of the candidate state change interval but does not appear continuously on the other side, the entry or exit of the electromechanical pipeline element is recorded. When the grouping relationship on both sides of the candidate state change interval is different, record the change in the grouping relationship; Retain candidate state change ranges where changes in the composition or grouping relationship of the electromechanical pipeline elements still exist after the refinement is completed; The midline of the candidate state change interval is determined as the boundary of the pipeline combination state change.

[0010] As a preferred embodiment of the present invention, in S400, the specific steps of determining the stable marking section along the extension direction of the projection pipeline segment include: Arrange the corresponding pipeline combination state change boundaries along the extension direction of each of the projected pipeline segments, and add the endpoints of the projected pipeline segments that do not coincide with the pipeline combination state change boundaries as end boundaries. The continuous projected pipeline segments between the state change boundaries or end boundaries of adjacent pipeline combinations in the arrangement are defined as the stable annotation segments. Compare the stable labeled sections located on both sides of the boundary of the state change of the same pipeline combination, and establish the pipeline continuity relationship between the stable labeled sections when they correspond to the same electromechanical pipeline element.

[0011] As a preferred embodiment of the present invention, in S400, the specific steps for forming the annotation group include: Obtain the projection pipeline segments whose extension ranges overlap and appear continuously within the overlapping range of the corresponding stable annotation sections; Determine the directional difference and centerline spacing between each pair of the projection pipeline segments; When the directional difference between any two projection pipeline segments is not greater than a preset directional deviation, and the centerline spacing is not greater than a preset grouping distance, it is determined that there is a grouping relationship between the two projection pipeline segments. Electromechanical pipeline elements corresponding to projected pipeline segments that are directly or indirectly associated through the grouping relationship are identified as belonging to the same annotation group.

[0012] As a preferred technical solution of the present invention, in S400, the specific steps of generating group-level annotations based on the attribute information corresponding to the annotation group include: Obtain the number of pipelines in each labeled group, as well as the pipe diameter or cross-sectional dimensions, system type, and elevation of each electromechanical pipeline element, and form a group attribute record; Compare adjacent label groups sequentially along the pipeline continuation relationship; If the electromechanical pipeline elements in the previous annotation group correspond one-to-one with the electromechanical pipeline elements in the next annotation group along the pipeline continuation relationship, and the group attribute records of the two annotation groups are the same, then the two annotation groups are merged, and the next adjacent annotation group is compared. When the correspondence between the electromechanical pipeline elements or the group attribute record changes, the merging process stops; One or more stable annotation segments corresponding to each annotation group obtained after comparison and merging are determined as continuous stable annotation segments; The group-level annotations are generated based on the group attribute records corresponding to each annotation group obtained after comparison and merging.

[0013] As a preferred technical solution of the present invention, in S500, the specific steps of determining the position adjustment range of the group-level annotation and adjusting the position of the annotation text and leader line of the group-level annotation include: Determine the two end boundaries of each stable annotation segment included in the continuous stable annotation segment along the extension direction of the corresponding projected pipeline segment, wherein the two end boundaries are the pipeline combination state change boundary or end boundary; The range along the extension direction of the corresponding projection pipeline segment is defined by the two end boundaries of each stable marking segment, and the preset avoidance distance is extended along the normal direction of the corresponding projection pipeline segment to obtain the position adjustment sub-range. Each of the aforementioned position adjustment sub-ranges is used as an independent candidate sub-range to form the position adjustment range of the group-level annotation; The candidate placement areas are obtained by excluding the areas occupied by the projection pipeline segments and other group-level annotations, as well as the annotation text and leaders, from each of the candidate sub-ranges. Within the candidate placement area, candidate placement positions are determined, and candidate placement positions that overlap with or intersect with other group-level annotations are excluded. The candidate placement position with the shortest corresponding lead length among the remaining candidate placement positions is determined as the position of the group-level label.

[0014] As a preferred embodiment of the present invention, the method further includes the following after S500: When the projected pipeline segment corresponding to the electromechanical pipeline element changes, for each scanning direction, the scanning line that intersects with the projected pipeline segment before and after the change is determined as the affected scanning line. The scan state corresponding to the affected scan line is re-formed, and the scan state corresponding to the adjacent scan lines is re-formed sequentially from both sides of the area occupied by the affected scan line outwards. The re-formed scan state is compared with the scan state corresponding to the same scan line before the change, and the attribute information of the corresponding electromechanical pipeline elements and the grouping relationship between the projected pipeline segments are compared. When scan lines with the same scanning state, attribute information, and grouping relationship as before the change appear on both sides of each scan direction, the outward expansion stops. The two-dimensional view area enclosed by each of the scan lines is defined as the update range; Re-execute S300 to S500 within the update range, while keeping the positions of group-level labels outside the update range unchanged.

[0015] The beneficial effects of this invention are: 1. By comparing the scanning states in two mutually perpendicular directions and refining the candidate state change interval, this invention can eliminate the change in the arrangement order of continuously existing electromechanical pipeline elements at the intersection position and accurately determine the boundary of pipeline combination state change.

[0016] 2. This invention forms annotation groups by establishing common occurrence relationships, directional relationships, and spacing relationships within stable annotation sections, and merges adjacent annotation groups based on pipeline continuity relationships and group attribute records. This can reduce duplicate group-level annotations and avoid incorrect grouping across pipeline combination changes.

[0017] 3. This invention improves the layout of group-level annotations by limiting the position adjustment range at both ends of the stable annotation section and excluding candidate placement positions with overlapping annotation text and intersecting leader lines. At the same time, it realizes local updates after changes in electromechanical pipeline elements by updating the range. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart illustrating the intelligent annotation method for electromechanical pipelines based on BIM 3D model drawing according to the present invention. Figure 2 This is a schematic diagram of the projection of electromechanical pipeline elements in the BIM view of this invention onto a two-dimensional view plane; Figure 3 This is the BIM view before the group-level labeling adjustment according to the present invention; Figure 4 This is the BIM view after the group-level annotation adjustment according to the present invention. Detailed Implementation

[0019] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] Example 1: As Figure 1 As shown, the present invention provides a method for intelligent annotation of electromechanical pipelines based on BIM 3D model generation, comprising: S100: Obtain the BIM view, extract the electromechanical pipeline elements and their geometric and attribute information from the BIM view, and project the electromechanical pipeline elements onto the two-dimensional view plane to obtain the projected pipeline segment; Specifically, the BIM view specified by the designer is used as the current processing object. The view element retrieval function of the BIM software is used to obtain the MEP (Mechanical, Electrical, and Piping) elements visible in the BIM view and belonging to the area to be labeled. For MEP elements that cross the display range boundary of the BIM view, only the portion within the display range is extracted.

[0021] In one embodiment, the BIM view is a plan view or a cross-sectional view, and the electromechanical pipeline elements include air ducts, water pipes, and cable trays.

[0022] For each electromechanical pipeline element, its element identifier, geometric information, and attribute information are read. The geometric information includes centerline, endpoints, and outer contour data used to determine the position and extension shape of the electromechanical pipeline element in three-dimensional space. The attribute information includes pipe diameter or cross-sectional dimensions, system type, and elevation. The system type is attribute information in the BIM model used to distinguish the electromechanical system to which the electromechanical pipeline belongs. A correspondence is established between the element identifier, geometric information, and attribute information.

[0023] Furthermore, based on the geometric information of all the electromechanical pipeline elements, the boundary position of each electromechanical pipeline element in three-dimensional space is determined, and the minimum and maximum boundary positions of all electromechanical pipeline elements in three coordinate directions are compared, thereby forming an overall three-dimensional bounding box that can enclose all the electromechanical pipeline elements.

[0024] like Figure 2 As shown, the two-dimensional view plane and viewing direction are read from the BIM view. The viewing direction is used as the projection direction, and each vertex of the overall three-dimensional bounding box is projected onto the two-dimensional view plane along the projection direction. The scanning processing range is determined based on the minimum and maximum positions of each projection point in two mutually perpendicular directions within the two-dimensional view plane. Figure 2 This illustrates the process of projecting electromechanical pipeline elements in a BIM view onto a two-dimensional view plane along the projection direction.

[0025] Following the same projection direction, the centerline and endpoints of each electromechanical pipeline element are projected onto the two-dimensional view plane, forming projected pipeline segments within the scanning processing range. When the centerline of the same electromechanical pipeline element comprises multiple continuous sections, corresponding projected pipeline segments are formed for each section. Each projected pipeline segment retains its correspondence with the element identifier and attribute information for subsequent scanning status generation and group-level annotation.

[0026] The scanning processing range is determined by the overall three-dimensional bounding box, so that subsequent processing is concentrated in the area where electromechanical pipeline elements actually exist, and it is ensured that each projected pipeline segment can be traced back to the corresponding electromechanical pipeline element.

[0027] S200: Using scan lines, scan along two mutually perpendicular directions in the two-dimensional view plane respectively, and form a scan state arranged along the corresponding scan direction based on the intersection of the scan lines and the projection pipeline segment, the corresponding electromechanical pipeline elements and their arrangement order; Specifically, two mutually perpendicular directions are selected within the two-dimensional view plane and used as scanning directions. For each scanning direction, a scan line perpendicular to the corresponding scanning direction is set, and the scan line moves sequentially from one side of the scanning processing range to the other along the corresponding scanning direction.

[0028] For each scan line, its intersection with the projected pipeline segment is calculated, and the electromechanical pipeline element and its identifier corresponding to each intersection are determined according to the correspondence retained in S100. All scan lines under the same scanning direction adopt the same arrangement direction. The electromechanical pipeline elements are arranged according to the position of each intersection on the corresponding scan line, thereby determining the arrangement order.

[0029] The primitive identifier, intersection position, and arrangement order corresponding to a scan line are recorded as the scan state corresponding to that scan line. The scan states are arranged according to the position of each scan line along the corresponding scan direction to obtain the scan states arranged along the two scan directions.

[0030] Furthermore, the preset scanning spacing refers to the distance between two adjacent scanning lines along the corresponding scanning direction. The preset scanning spacing is read from the annotation configuration corresponding to the current BIM view before scanning begins, and can be set according to the view scale, drawing standards, or user preferences.

[0031] Starting from one side of the scanning processing range along the corresponding scanning direction, parallel scan lines are sequentially set according to the preset scan interval. Each scan line is perpendicular to the corresponding scanning direction and penetrates the scanning processing range. When there is still an uncovered area between the last scan line set according to the preset scan interval and the other boundary of the scanning processing range, the scan line located at the other boundary is taken as the last scan line in that scanning direction. In one embodiment, the preset scan interval is 500 mm.

[0032] For the same scan line, one end of the scan line is designated as the starting point for arrangement, and the intersection points are arranged in ascending order of their distance from the starting point. Based on the correspondence between the projected pipeline segments and the electromechanical pipeline elements, the element identifier, intersection position, and arrangement order of each intersection point are recorded sequentially to form the scan state corresponding to that scan line. All scan lines under the same scanning direction use the same starting point direction to ensure that the arrangement order in adjacent scan states can be directly compared.

[0033] By scanning in two mutually perpendicular directions, the distribution of the projected pipeline segments in the two-dimensional view plane is converted into a sequentially arranged scanning state, providing a data basis for subsequent comparison of adjacent scanning states and determination of the boundary of pipeline combination state change.

[0034] S300: Compare adjacent scanning states, combine the scanning states in another scanning direction to eliminate the influence of changes in the arrangement order of continuously existing electromechanical pipeline elements on boundary determination, and determine the pipeline combination state change boundary based on changes in the composition of the electromechanical pipeline elements or changes in the grouping relationship between the projected pipeline segments. Specifically, for each scanning direction, adjacent scanning states are compared sequentially according to their arrangement along the corresponding scanning direction. The composition of electromechanical pipeline elements is determined based on the element identifiers in adjacent scanning states; the arrangement order is determined based on the element identifiers; and the grouping relationship between commonly appearing projected pipeline segments is compared to determine if it has changed.

[0035] When the aforementioned changes exist between adjacent scan states, the candidate state change interval where the change occurs is first determined, and then the candidate state change interval is gradually narrowed by adding more refined scan lines. After refinement, the scan state in another scan direction is used to determine whether the relevant electromechanical pipeline elements exist continuously, thereby distinguishing between changes in the arrangement order caused by the intersection of continuous pipelines and changes in the actual composition or grouping relationship of electromechanical pipeline elements.

[0036] Furthermore, the specific steps for comparing adjacent scan states include: All element identifiers recorded in a scan state are used as the composition of the electromechanical pipeline elements corresponding to that scan state, and the order of the element identifiers arranged according to their intersection positions is used as the arrangement order corresponding to that scan state. When the element identifiers contained in adjacent scan states are not completely identical, it is determined that the composition of the electromechanical pipeline elements has changed. When the element identifiers contained in adjacent scan states are the same but arranged in different orders, it is determined that the arrangement order has changed.

[0037] For projection pipeline segments that appear together in the same scanning state, the directional difference and centerline spacing are determined based on the centerlines of each projection pipeline segment. The directional difference is the smaller angle between the extending directions of the centerlines of the two projection pipeline segments. The centerline spacing is the distance between the centerlines of the two projection pipeline segments at corresponding positions in the corresponding scanning state.

[0038] The preset direction deviation is the maximum permissible direction difference used to determine whether two commonly appearing projected pipeline segments satisfy the directional relationship. The preset direction deviation is read from the annotation configuration corresponding to the current BIM view before the scan comparison and can be set according to drawing standards or user preferences.

[0039] The preset grouping distance is the maximum allowable centerline spacing used to determine whether two commonly appearing projected pipeline segments satisfy the spacing relationship. The preset grouping distance is read from the annotation configuration corresponding to the current BIM view before the scan comparison, and can be set according to the view scale, drawing standards, or user preferences.

[0040] When the directional difference between two projection pipeline segments is not greater than a preset directional deviation, and the centerline spacing is not greater than a preset grouping distance, a grouping relationship is determined to exist between the two projection pipeline segments. The grouping relationship in adjacent scanning states is determined in the same manner, and the grouping relationship is compared to see if it changes. In one embodiment, the preset grouping distance is 1000 mm.

[0041] When at least one of the components, arrangement order, or grouping relationship of electromechanical pipeline elements in adjacent scan states changes, the area between the corresponding two adjacent scan lines is determined as the candidate state change interval.

[0042] A thinner scan line parallel to the two side scan lines is added at the middle position of the candidate state change interval, and the scan state corresponding to the thinner scan line is formed in the same way as in S200. The scan states corresponding to the thinner scan line and its two adjacent scan lines are compared respectively, and the adjacent scan lines that still have changes in the composition, arrangement order or grouping relationship of electromechanical pipeline elements are re-determined as candidate state change intervals. When there are changes on both sides of the thinner scan line, both sides are treated as candidate state change intervals for further processing.

[0043] Within the newly defined candidate state change interval, refined scan lines are repeatedly added until the width of the candidate state change interval is no greater than the preset boundary width. The width of the candidate state change interval is the distance between two adjacent scan lines constituting the candidate state change interval along the corresponding scan direction.

[0044] The preset boundary width is the maximum width allowed to be retained when the candidate state change interval stops refining. The preset boundary width is read from the annotation configuration corresponding to the current BIM view before the candidate state change interval is refined, and can be set according to the view scale and boundary positioning accuracy requirements.

[0045] Furthermore, the specific steps for determining the boundary of pipeline combination state change include: Based on the element identifier, the electromechanical pipeline elements on both sides of the refined candidate state change interval are matched. For the same element identifier that exists in both scanning states, the intersection record of the corresponding electromechanical pipeline element is found in the scanning state of the other scanning direction.

[0046] When the intersection record can be continuously traced from one side to the other side of the candidate state change interval along the same projected pipeline segment or the continuous projected pipeline segment corresponding to the same electromechanical pipeline element, it is determined that the electromechanical pipeline element exists continuously within the candidate state change interval.

[0047] When the electromechanical pipeline elements on both sides of the candidate state change interval are identical, and the matched electromechanical pipeline elements are all continuously present, the change in the arrangement order in the scanning states on both sides is not used as the basis for determining the boundary of the pipeline combination state change. This eliminates erroneous boundaries caused by the exchange of arrangement order of continuous electromechanical pipeline elements at the intersection.

[0048] When a graphic element identifier did not appear in the scan states preceding the candidate state change interval along the corresponding scan direction, but appeared consecutively in subsequent scan states, the entry of the corresponding electromechanical pipeline graphic element is recorded. When a graphic element identifier appeared consecutively in the scan states preceding the candidate state change interval along the corresponding scan direction, but did not appear in subsequent scan states, the exit of the corresponding electromechanical pipeline graphic element is recorded. When the grouping relationship on both sides of the candidate state change interval is different, the change in the grouping relationship is recorded.

[0049] Candidate state change intervals that only involve changes in the arrangement order of continuous electromechanical pipeline elements are discarded, while candidate state change intervals that also involve changes in the composition or grouping relationship of electromechanical pipeline elements are retained. The midline of the retained candidate state change interval is determined as the boundary of the pipeline combination state change. The midline is parallel to the two scan lines that constitute the corresponding candidate state change interval, and is equidistant from the two scan lines.

[0050] The above processing is performed on both scanning directions to obtain the pipeline combination state change boundary used to determine the stable labeled section.

[0051] S400: Using the boundary of the pipeline combination state change as the boundary, determine a stable annotation section along the extension direction of the projected pipeline segment, form an annotation group according to the common occurrence relationship, directional relationship and spacing relationship of the projected pipeline segment in the stable annotation section, and generate group-level annotations according to the attribute information corresponding to the annotation group; Specifically, the pipeline combination state change boundary obtained in S300 is mapped to the projected pipeline segments. Based on the position of the pipeline combination state change boundary on each projected pipeline segment, the projected pipeline segments are divided to obtain stable annotation sections. Within these stable annotation sections, annotation groups are formed based on the common occurrence, directional, and spacing relationships of the projected pipeline segments. Adjacent annotation groups are compared along the continuity direction of the same electromechanical pipeline element to reduce repetitive group-level annotations generated by continuous pipelines.

[0052] Furthermore, the specific steps for determining the stable annotation section along the extension direction of the projection pipeline segment include: For each projected pipeline segment, the pipeline combination state change boundary intersecting with the projected pipeline segment is determined, and the pipeline combination state change boundaries are arranged sequentially along the extension direction of the projected pipeline segment according to their positions on the projected pipeline segment.

[0053] For the endpoints of projected pipeline segments that do not coincide with the boundary of pipeline combination state change, they are designated as end boundaries and added to the corresponding arrangement. When the endpoints of projected pipeline segments coincide with the boundary of pipeline combination state change, the end boundaries are not set again.

[0054] Continuous projected pipeline segments between adjacent pipeline combination state change boundaries or end boundaries in the arrangement are defined as stable annotation segments. Each stable annotation segment retains its corresponding primitive identifier, attribute information, and pipeline combination state change boundaries or end boundaries at both ends.

[0055] Compare stable labeled sections located on either side of the boundary of the same pipeline combination state change. When two stable labeled sections correspond to the same electromechanical pipeline element, establish a pipeline continuity relationship between the two stable labeled sections. The pipeline continuity relationship is used to represent the continuous correspondence of the same electromechanical pipeline element between adjacent stable labeled sections.

[0056] Furthermore, the specific steps for forming the annotation group include: The extension range of each stable annotation segment is determined based on the positions of its two ends. When the extension ranges of stable annotation segments corresponding to different projected pipeline segments overlap, the overlapping portion is determined as the common occurrence range.

[0057] Based on the scanning state formed in S200, check whether the graphic element identifiers corresponding to the corresponding projection pipeline segments appear continuously within the common occurrence range. If the corresponding graphic element identifiers continuously exist within the common occurrence range, it is determined that the projection pipeline segments satisfy the common occurrence relationship.

[0058] For projected pipeline segments that satisfy the co-occurrence relationship, the directional difference and centerline spacing between any two projected pipeline segments are determined. The directional difference and centerline spacing are determined in the same way as in S300, and the preset directional deviation and preset grouping distance are set in the same way as in S300, and remain unchanged during the processing of the same BIM view.

[0059] When the directional difference between any two projection pipeline segments is not greater than the preset directional deviation, and the centerline spacing is not greater than the preset grouping distance, it is determined that there is a grouping relationship between the two projection pipeline segments.

[0060] Starting with a projected pipeline segment that has not yet formed a label group, add projected pipeline segments that have a grouping relationship with it to the same label group, and continue searching for other projected pipeline segments that have a grouping relationship with the already added projected pipeline segments, until no new projected pipeline segments can be added. Thus, the electromechanical pipeline elements corresponding to projected pipeline segments that are directly or indirectly related through grouping relationships are identified as belonging to the same label group.

[0061] Furthermore, the specific steps for generating group-level annotations based on the attribute information corresponding to the annotation group include: For each annotation group, the number of pipelines in the electromechanical pipeline elements included in the annotation group is counted, and the pipe diameter or cross-sectional dimensions, system type and elevation of each electromechanical pipeline element are read according to the element identifier. The group attribute record is formed by the number of pipelines and the above attribute information of each electromechanical pipeline element.

[0062] Determine adjacent annotation groups sequentially along the pipeline continuation relationship. For two adjacent annotation groups, check whether all electromechanical pipeline elements in the preceding annotation group can correspond to the electromechanical pipeline elements in the following annotation group through the pipeline continuation relationship, and check whether there are any uncorresponding electromechanical pipeline elements in the following annotation group.

[0063] When the electromechanical pipeline elements in two annotation groups correspond one-to-one and the group attribute records of the two annotation groups are the same, the two annotation groups are merged, and the comparison continues with the next adjacent annotation group. When the electromechanical pipeline elements cannot correspond one-to-one or the group attribute records change, the merging stops.

[0064] After comparison and merging, one or more stable label segments corresponding to each label group are determined as continuous stable label segments. Stable label segments corresponding to label groups that have not been merged with adjacent label groups constitute continuous stable label segments on their own.

[0065] Group-level annotations are generated based on the group attribute records corresponding to each annotation group obtained after comparison and merging. The group-level annotations include annotation text and leader lines. The annotation text is written according to the annotation style adopted by the current BIM view, including the number of pipelines, pipe diameter or cross-sectional dimensions, system type, and elevation. The leader lines are associated with the corresponding annotation groups.

[0066] In one implementation, the initial position of the group-level annotation is set near the geometric center of the corresponding annotation group. This initial position serves only as the placement location when the group-level annotation is generated; subsequently, in step S500, the positions of the annotation text and leader lines are adjusted according to the position adjustment range.

[0067] S500: Determine the position adjustment range of the group-level annotation based on both ends of the stable annotation section along the extension direction of the projection pipeline segment, adjust the position of the annotation text and leader of the group-level annotation within the position adjustment range, and output the adjusted group-level annotation to the BIM view.

[0068] Specifically, based on the two ends of each stable annotation segment included in the continuous stable annotation segment along the extension direction of the corresponding projection pipeline segment, the range in which the group-level annotation can move along the extension direction of the projection pipeline segment is defined, and an area in the normal direction of the range in which annotation text and leaders can be placed is determined.

[0069] Exclude areas already occupied by projected pipeline segments and other group-level annotations within the specified position adjustment range. Adjust the positions of the annotation text and leaders of the group-level annotations based on whether the annotation text overlaps, whether the leaders intersect, and the leader length. After completing the position adjustment of all group-level annotations, write the group-level annotations into the corresponding BIM view.

[0070] Furthermore, the specific steps for determining the adjustment range of the group-level annotation and adjusting the position of the annotation text and leader line of the group-level annotation include: For each continuous stable annotation segment, the two end boundaries of each stable annotation segment contained therein along the extension direction of the corresponding projected pipeline segment are determined. The two end boundaries are either the pipeline combination state change boundary or the end boundary.

[0071] The range along the extension direction of the corresponding projection pipeline segment is defined by the two ends of each stable annotation segment, and the preset avoidance distance is extended to both sides along the normal direction of the corresponding projection pipeline segment to obtain the position adjustment sub-range corresponding to the stable annotation segment.

[0072] The preset avoidance distance is the distance that the position adjustment sub-range extends to both sides along the normal direction relative to the corresponding projected pipeline segment. The preset avoidance distance is read from the annotation configuration corresponding to the current BIM view before determining the position adjustment sub-range, and can be set according to the annotation text size, view scale, and drawing standards.

[0073] When a continuous stable annotation segment contains multiple stable annotation segments, a position adjustment sub-range is formed for each stable annotation segment, and each position adjustment sub-range is treated as an independent candidate sub-range. All candidate sub-ranges together form the position adjustment range of the corresponding group-level annotation, enabling the group-level annotation to be adjusted within any candidate sub-range without crossing the two boundaries of the corresponding stable annotation segment.

[0074] The area occupied by the projected pipeline segment is determined based on its display position and line width in the 2D view plane. The area occupied by the annotation text is determined based on the outer contour of the annotation text of other group-level annotations. The area occupied by the leader is determined based on the leader path and line width of other group-level annotations. The above occupied areas are excluded from each candidate sub-range to obtain the candidate placement area.

[0075] Based on the outer contour dimensions of the annotation text to be placed, a position that can completely accommodate the annotation text is found within each candidate placement area. For each continuous area that can completely accommodate the annotation text, the position closest to the corresponding annotation group is selected as the candidate placement position.

[0076] For each candidate placement location, a leader line connecting the corresponding annotation group and the annotation text is generated. The process checks whether the annotation text overlaps with the annotation text of other group-level annotations, and whether the leader line intersects with the leader lines of other group-level annotations. Candidate placement locations that result in overlapping annotation text or intersecting leader lines are excluded.

[0077] The leader length is the sum of the lengths of each segment of the leader extending from the connection position of the corresponding annotation group to the connection position of the annotation text. The leader lengths corresponding to the remaining candidate placement positions are compared, and the candidate placement position with the shortest leader length is determined as the position of the group-level annotation.

[0078] The group-level annotations are processed sequentially according to the arrangement order of continuous and stable annotation segments in the BIM view. Once the position of each group-level annotation is determined, its annotation text and leader area are added to the already occupied area before processing the next group-level annotation. This avoids conflicts between subsequently adjusted group-level annotations and those already adjusted.

[0079] After adjusting the positions of all group-level annotations, the annotation text and leader lines are written into the BIM view according to the determined positions and the annotation style used in the current BIM view through the annotation generation interface of the BIM software. Each group-level annotation retains its association with the corresponding annotation group and MEP (Mechanical, Electrical, and Pipeline) elements, so as to update when MEP elements change.

[0080] Furthermore, following the S500 are also: After initial annotation, save each projected pipeline segment, scan line, scan status, grouping relationship, attribute information, and the position of group-level annotations. When the BIM model is modified and the projected pipeline segments corresponding to the MEP pipeline elements change, obtain the projected pipeline segments before and after the change.

[0081] For each scanning direction, find the scan lines that intersect with either the original or changed projection pipeline segment, and identify these scan lines as the affected scan lines. Recalculate the intersection points between each affected scan line and the changed projection pipeline segment, and reconstruct the scanning state corresponding to the affected scan lines in the same manner as in S200.

[0082] Starting from the area occupied by the affected scan line and moving outwards along both sides of the corresponding scan direction, the scan states corresponding to adjacent scan lines are sequentially re-formed. The re-formed scan states are then compared with the scan states corresponding to the same scan line before the change.

[0083] The comparison of scan status includes element identifiers, intersection positions, and arrangement order. It also compares the attribute information of corresponding electromechanical pipeline elements and the grouping relationships between projected pipeline segments. The attribute information includes pipe diameter or cross-sectional dimensions, system type, and elevation.

[0084] When the element identifiers, intersection positions, and arrangement order in the re-formed scan state are the same as before the change, the attribute information of the corresponding electromechanical pipeline elements is the same as before the change, and the grouping relationship between the projected pipeline segments is the same as before the change, it is determined that the processing state at that scan line has not been affected by this change.

[0085] When unaffected scan lines appear on both sides of the area occupied by the affected scan line in each scanning direction, the outward expansion stops. Since the two scanning directions are perpendicular to each other, the corresponding scan lines on both sides of each scanning direction together enclose a two-dimensional view area, which is defined as the update range.

[0086] Within the update range, steps S300 to S500 are performed using the newly formed scan state to redetermine the pipeline combination state change boundaries, stable annotation sections, annotation groups, group-level annotations, and the positions of group-level annotations. For group-level annotations outside the update range, no position adjustment is performed, and their positions remain unchanged.

[0087] By comparing the processing status before and after the change from the affected scan line outwards, the update scope is limited to the area where the status change is actually caused by the change of MEP pipeline elements, thereby avoiding reprocessing the entire BIM view every time the BIM model is modified. Example

[0088] This embodiment uses the MEP (Mechanical, Electrical, and Plumbing) integrated plan of a standard floor of a large office building as an example. After completing the MEP integrated model of the standard floor in BIM software, the engineering designers need to generate the construction plan. The BIM view includes MEP pipeline elements such as air ducts, air conditioning water pipes, fire water pipes, and cable trays, and there are a large number of parallel, intersecting, turning, and branching pipelines near corridors and equipment rooms. When manually setting labels for each pipeline, duplicate labels, overlapping label text, and intersecting leader lines are prone to occur. Therefore, the method of this invention is used to generate and adjust group-level labels.

[0089] After executing the method of this invention, the geometric and attribute information of each electromechanical pipeline element is first extracted from the BIM view, and the electromechanical pipeline elements are projected onto the two-dimensional view plane. For example... Figure 2 As shown, the scanning processing range is obtained based on the overall three-dimensional bounding box of all electromechanical pipeline elements, thereby limiting subsequent scanning and annotation processing to the area corresponding to the current output content.

[0090] In one implementation, a preset scanning interval is set to 500 mm, and scanning states are formed along two mutually perpendicular scanning directions. At corridor turns and pipeline intersections, the arrangement order of some projected pipeline segments changes in adjacent scanning states. The scanning state in the other scanning direction confirms that the corresponding electromechanical pipeline elements still exist continuously, therefore the change in arrangement order is not used as the basis for determining the boundary of pipeline combination state changes. For locations where pipeline branches, pipeline ends, or grouping relationships change, the boundary of pipeline combination state changes is determined by candidate state change intervals and refined scanning lines. This avoids misjudging normal intersections of projected pipeline segments as changes in pipeline combination state, while simultaneously identifying actual locations where pipeline entry, exit, or grouping relationship changes occur.

[0091] Stable annotation sections are formed by defining the boundary of the pipeline combination state change. In the corridor area of ​​this embodiment, four air conditioning water pipes with a diameter of DN150, the same system type, and an elevation of +3.000 meters appear consecutively. Their directional difference is no greater than a preset directional deviation, and the centerline spacing is no greater than 1000 mm. Therefore, they are identified as the same annotation group. The number of pipelines, pipe diameter, system type, and elevation of this annotation group form a group attribute record. When the electromechanical pipeline elements in adjacent stable annotation sections correspond one-to-one along the pipeline continuity relationship and the group attribute records are the same, the corresponding annotation groups are continuously merged and a group-level annotation is generated to avoid repeatedly setting the same annotation content at different locations of the same group of pipelines.

[0092] For pipelines whose group attribute records near equipment rooms change, they are no longer merged with the previous annotation group. Instead, a separate group-level annotation is generated within the corresponding continuous and stable annotation section. As a result, the merging scope of group-level annotations is consistent with the actual continuity status and attribute information of electromechanical pipeline elements, which reduces redundant annotations and avoids the sharing of incorrect annotations by pipelines of different diameters, different system types, or different elevations.

[0093] After generating group-level annotations, the position adjustment range is determined based on both ends of the corresponding stable annotation segment along the extension direction of the projected pipeline segment. Within this position adjustment range, the area occupied by the annotation text and leaders of the projected pipeline segment and other group-level annotations is excluded, and the position with the shortest corresponding leader length is selected from the remaining candidate placement positions. For example... Figure 3 As shown, before the adjustment, multiple annotation texts were concentrated at pipeline intersections, with some annotation texts overlapping and leader lines intersecting; for example... Figure 4 As shown, after the position adjustment, the group-level labels are distributed within the corresponding position adjustment range, there is no overlap between the label texts, no intersection between the leader lines, and the group-level labels still maintain a clear association with the corresponding electromechanical pipeline elements.

[0094] When designers subsequently adjust a section of air conditioning water pipe at a corridor bend, they only reprocess the affected scan lines that intersect with the projected pipe segments before and after the change. The update range is determined based on the scan status, attribute information, and grouping relationships before and after the change. Within this update range, the boundaries of pipe combination status changes, stable annotation sections, annotation groups, and the positions of group-level annotations are redefined. Simultaneously, the positions of group-level annotations outside the update range remain unchanged, thus avoiding a rearrangement of annotations throughout the entire BIM view caused by local model modifications.

[0095] As can be seen from the above practical scenarios, this invention utilizes the scanning states of two scanning directions to distinguish between changes in the arrangement order caused by pipeline intersections and changes in the actual pipeline combination state, and defines stable annotation sections and position adjustment ranges by the boundaries of pipeline combination state changes. While reducing redundant annotations, it can avoid overlapping annotation text and leader line intersections, and maintain the stability of group-level annotations in unaffected areas when electromechanical pipeline elements undergo local changes, reducing the workload of manual annotation and subsequent adjustments.

[0096] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing, characterized in that, include: S100: Obtain the BIM view, extract the electromechanical pipeline elements and their geometric and attribute information from the BIM view, and project the electromechanical pipeline elements onto the two-dimensional view plane to obtain the projected pipeline segment; S200: Using scan lines, scan along two mutually perpendicular directions in the two-dimensional view plane respectively, and form a scan state arranged along the corresponding scan direction based on the intersection of the scan lines and the projection pipeline segment, the corresponding electromechanical pipeline elements and their arrangement order; S300: Compare adjacent scanning states, combine the scanning states in another scanning direction to eliminate the influence of changes in the arrangement order of continuously existing electromechanical pipeline elements on boundary determination, and determine the pipeline combination state change boundary based on changes in the composition of the electromechanical pipeline elements or changes in the grouping relationship between the projected pipeline segments. S400: Using the boundary of the pipeline combination state change as the boundary, determine a stable annotation section along the extension direction of the projected pipeline segment, form an annotation group according to the common occurrence relationship, directional relationship and spacing relationship of the projected pipeline segment in the stable annotation section, and generate group-level annotations according to the attribute information corresponding to the annotation group; S5 00: Determine the position adjustment range of the group-level annotation based on both ends of the stable annotation section along the extension direction of the projection pipeline segment, adjust the position of the annotation text and leader line of the group-level annotation within the position adjustment range, and output the adjusted group-level annotation to the BIM view.

2. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 1, characterized in that, In S100, the specific steps of projecting the electromechanical pipeline elements onto the two-dimensional view plane include: The overall three-dimensional bounding box of all the electromechanical pipeline elements is determined based on the geometric information of the electromechanical pipeline elements; The overall three-dimensional bounding box is projected onto the two-dimensional view plane to obtain the scanning processing range; The geometric information of the electromechanical pipeline elements is projected onto the two-dimensional view plane to obtain the projected pipeline segment located within the scanning processing range.

3. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 2, characterized in that, In S200, the specific steps for forming the scan states arranged along the corresponding scan direction include: For each scanning direction, within the scanning processing range, scanning lines that are parallel to each other and perpendicular to the corresponding scanning direction are set at a preset scanning interval; Determine the intersection point of the scan line and the projection pipeline segment, and arrange the corresponding electromechanical pipeline elements according to the position of the intersection point on the corresponding scan line; Record the element identifiers, intersection positions, and arrangement order of the electromechanical pipeline elements to form the scanning state corresponding to each scan line, and arrange the scanning states according to the arrangement order of the scan lines along the corresponding scanning direction.

4. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 3, characterized in that, In S300, the specific steps for comparing adjacent scan states include: The composition and arrangement order of electromechanical pipeline elements in adjacent scanning states are compared to determine the directional difference and centerline spacing between commonly appearing projection pipeline segments. The grouping relationship is determined based on the comparison results of the directional difference with the preset directional deviation and the centerline spacing with the preset grouping distance. The adjacent scan lines where the composition, arrangement order, or grouping relationship of the electromechanical pipeline elements changes are identified as candidate state change intervals. Within the candidate state change range, a thinner scan line parallel to the adjacent scan line is added, and the scan state corresponding to the thinner scan line is formed. By comparing the scan states of the refined scan line with those of its adjacent scan lines, the adjacent scan lines that still have changes in the composition, arrangement order or grouping relationship of the electromechanical pipeline elements are re-determined as candidate state change intervals. Within the newly determined candidate state change interval, the refined scan lines are continued to be added until the width of the candidate state change interval is no greater than the preset boundary width.

5. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 4, characterized in that, In S300, the specific steps for determining the boundary of pipeline combination state change include: The electromechanical pipeline elements on both sides of the candidate state change interval are matched according to the element identifier, and the continuity of the matched electromechanical pipeline elements in the candidate state change interval is determined according to the scanning state in another scanning direction. When the electromechanical pipeline elements on both sides of the candidate state change interval are the same and the matching electromechanical pipeline elements exist continuously, the change in the arrangement order within the candidate state change interval is not used as the basis for determining the boundary of the pipeline combination state change. When the electromechanical pipeline element appears continuously on one side of the candidate state change interval but does not appear continuously on the other side, the entry or exit of the electromechanical pipeline element is recorded. When the grouping relationship on both sides of the candidate state change interval is different, record the change in the grouping relationship; Retain candidate state change ranges where changes in the composition or grouping relationship of the electromechanical pipeline elements still exist after the refinement is completed; The midline of the candidate state change interval is determined as the boundary of the pipeline combination state change.

6. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 1, characterized in that, In S400, the specific steps for determining the stable annotation section along the extension direction of the projection pipeline segment include: Arrange the corresponding pipeline combination state change boundaries along the extension direction of each of the projected pipeline segments, and add the endpoints of the projected pipeline segments that do not coincide with the pipeline combination state change boundaries as end boundaries. The continuous projected pipeline segments between the state change boundaries or end boundaries of adjacent pipeline combinations in the arrangement are defined as the stable annotation segments. Compare the stable labeled sections located on both sides of the boundary of the state change of the same pipeline combination, and establish the pipeline continuity relationship between the stable labeled sections when they correspond to the same electromechanical pipeline element.

7. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 6, characterized in that, In S400, the specific steps for forming the annotation group include: Obtain the projection pipeline segments whose extension ranges overlap and appear continuously within the overlapping range of the corresponding stable annotation sections; Determine the directional difference and centerline spacing between each pair of the projection pipeline segments; When the directional difference between any two projection pipeline segments is not greater than a preset directional deviation, and the centerline spacing is not greater than a preset grouping distance, it is determined that there is a grouping relationship between the two projection pipeline segments. Electromechanical pipeline elements corresponding to projected pipeline segments that are directly or indirectly associated through the grouping relationship are identified as belonging to the same annotation group.

8. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 7, characterized in that, In S400, the specific steps for generating group-level annotations based on the attribute information corresponding to the annotation group include: Obtain the number of pipelines in each labeled group, as well as the pipe diameter or cross-sectional dimensions, system type, and elevation of each electromechanical pipeline element, and form a group attribute record; Compare adjacent label groups sequentially along the pipeline continuation relationship; If the electromechanical pipeline elements in the previous annotation group correspond one-to-one with the electromechanical pipeline elements in the next annotation group along the pipeline continuation relationship, and the group attribute records of the two annotation groups are the same, then the two annotation groups are merged, and the next adjacent annotation group is compared. When the correspondence between the electromechanical pipeline elements or the group attribute record changes, the merging process stops; One or more stable annotation segments corresponding to each annotation group obtained after comparison and merging are determined as continuous stable annotation segments; The group-level annotations are generated based on the group attribute records corresponding to each annotation group obtained after comparison and merging.

9. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 8, characterized in that, In S500, the specific steps for determining the position adjustment range of the group-level annotation and adjusting the position of the annotation text and leader line of the group-level annotation include: Determine the two end boundaries of each stable annotation segment included in the continuous stable annotation segment along the extension direction of the corresponding projected pipeline segment, wherein the two end boundaries are the pipeline combination state change boundary or end boundary; The range along the extension direction of the corresponding projection pipeline segment is defined by the two end boundaries of each stable marking segment, and the preset avoidance distance is extended along the normal direction of the corresponding projection pipeline segment to obtain the position adjustment sub-range. Each of the aforementioned position adjustment sub-ranges is used as an independent candidate sub-range to form the position adjustment range of the group-level annotation; The candidate placement areas are obtained by excluding the areas occupied by the projection pipeline segments and other group-level annotations, as well as the annotation text and leaders, from each of the candidate sub-ranges. Within the candidate placement area, candidate placement positions are determined, and candidate placement positions that overlap with or intersect with other group-level annotations are excluded. The candidate placement position with the shortest corresponding lead length among the remaining candidate placement positions is determined as the position of the group-level label.

10. The method for intelligent annotation of electromechanical pipelines based on BIM 3D model drawing according to claim 1, characterized in that, Following the S500 are: When the projected pipeline segment corresponding to the electromechanical pipeline element changes, for each scanning direction, the scanning line that intersects with the projected pipeline segment before and after the change is determined as the affected scanning line. The scan state corresponding to the affected scan line is re-formed, and the scan state corresponding to the adjacent scan lines is re-formed sequentially from both sides of the area occupied by the affected scan line outwards. The re-formed scan state is compared with the scan state corresponding to the same scan line before the change, and the attribute information of the corresponding electromechanical pipeline elements and the grouping relationship between the projected pipeline segments are compared. When scan lines with the same scanning state, attribute information, and grouping relationship as before the change appear on both sides of each scan direction, the outward expansion stops. The two-dimensional view area enclosed by each of the scan lines is defined as the update range; Re-execute S300 to S500 within the update range, while keeping the positions of group-level labels outside the update range unchanged.

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