CN113591739A

CN113591739A - Method and device for identifying face area in drawing, computer equipment and storage medium

Info

Publication number: CN113591739A
Application number: CN202110890139.8A
Authority: CN
Inventors: 刘建雄
Original assignee: Glodon Co Ltd
Current assignee: Glodon Co Ltd
Priority date: 2021-08-04
Filing date: 2021-08-04
Publication date: 2021-11-02
Anticipated expiration: 2041-08-04
Also published as: CN113591739B

Abstract

The invention provides a method, a device, computer equipment and a storage medium for identifying a face area in a drawing. The method comprises the following steps: reading the cells in the cell queue to obtain target cells, wherein the cells are areas with preset sizes and shapes, and the initial cells generated in the area to be identified in the drawing are used as the first cells in the cell queue; detecting whether the target cell has an intersecting line or not; if the target cell has an intersecting line, determining the intersecting line as a key line; if the target cell does not have an intersecting line, obtaining a cell adjacent to the target cell in the drawing and adding the cell into a cell queue; and when the cell queue is emptied, carrying out polygon search according to all the key lines to identify the face area. By the method and the device, the area searching efficiency can be improved.

Description

Method and device for identifying face area in drawing, computer equipment and storage medium

Technical Field

The invention relates to the technical field of BIM calculation, in particular to a method and a device for identifying a face area in a drawing, computer equipment and a storage medium.

Background

In different subdivision fields of the BIM calculation amount industry, identification of irregular areas in different types of drawings such as CAD (computer-aided design) drawings and PDF (Portable document Format) drawings is involved, the main purpose and the function of identification are to quickly pick up irregular polygons, namely surface areas, on the drawings, further support different businesses to generate corresponding models according to the polygons, and improve BIM calculation amount efficiency.

In the prior art, the basic principle of identifying irregular surface areas is that: taking all lines in the drawing as a search range, finding a reference line nearby the reference line according to a reference point, and then finding subsequent connecting lines step by step through a certain depth traversal algorithm according to the connection relation of the lines until the lines are closed. For a concise and clear drawing, namely a drawing which is clearly divided from the angles of layers, colors or styles and the like and has few simultaneous occurrence of different professional elements, the method in the prior art has low searching complexity and high efficiency.

However, as elements contained in the drawing are more and more complex, especially when the drawing is a complex drawing with criss-cross lines, the method is low in search efficiency and poor in user experience.

Therefore, how to improve the recognition efficiency of irregular surface areas in complex drawings becomes a technical problem to be solved urgently in the field.

Disclosure of Invention

The present invention is directed to a method, an apparatus, a computer device and a storage medium for identifying a face area in a drawing, which are used to solve the above technical problems in the prior art.

In one aspect, the present invention provides a method for identifying a face region in a drawing.

The method for identifying the face area in the drawing comprises the following steps: reading cells in a cell queue to obtain a target cell, wherein the cell is an area with a preset size and a preset shape, and an initial cell generated in a face area to be identified in a drawing is used as a first cell in the cell queue; detecting whether the target cell has an intersecting line or not; if the target cell has an intersecting line, determining the intersecting line as a key line; if the target cell does not have an intersecting line, the cell adjacent to the target cell is obtained from the drawing and added into the cell queue; and when the cell queue is emptied, performing polygon search according to all the key lines to identify the face area.

Further, generating the initial cell in the area to be identified in the drawing comprises: acquiring the proportion of the drawing; determining the size of the unit cell according to the proportion; determining the position of the initial cell in the area to be identified in the drawing according to user operation; and generating the initial cell according to the size of the cell and the position of the initial cell.

Further, the method further comprises: extracting all lines in the drawing, determining a bounding box of each line, and storing the corresponding relation between the lines and the bounding boxes thereof; detecting whether the target cell has the intersecting line or not comprises the following steps: and searching the bounding box intersected with the target cell to obtain a target bounding box, and detecting whether lines corresponding to the target cell and the target bounding box are intersected or not.

Further, the method further comprises: after determining the bounding box of the line, storing maximum point coordinates Nmax (x, y) and minimum point coordinates Nmin (x, y) of the bounding box in a four-quadrant based tree data structure; searching the bounding box intersected with the target cell to obtain a target bounding box comprises the following steps: calculating the maximum point coordinate Bmax (x, y) and the minimum point coordinate Bmin (x, y) of the target cell; comparing the maximum point coordinate Nmax (x, y) of the bounding box at the current node in the tree data structure with the minimum point coordinate Bmin (x, y) of the target cell; when Nmax.x > Bmin.x, and Nmax.y < Bmin.y, determining that the bounding box at the current node in the tree data structure is the target bounding box; comparing the minimum point coordinate Nmin (x, y) of the bounding box at the current node in the tree data structure with the maximum point coordinate Bmax (x, y) of the target cell; when Nmin.x < Bmax.x and Nmin.y > Bmax.y, determining that the next node is the node in the first quadrant of the current node in the tree-like data structure; when Nmin.x is less than Bmax.x and Nmin.y is less than Bmax.y, determining the next node as the node in the fourth quadrant of the current node in the tree-shaped data structure; when Nmin.x > Bmax.x and Nmin.y > Bmax.y, determining the next node as the node in the second quadrant of the current node in the tree-like data structure; when Nmin.x > Bmax.x and Nmin.y < Bmax.y, determining the next node as the node in the third quadrant of the current node in the tree data structure.

Further, the method further comprises: storing the cells added into the cell queue into a rendering list; reading data in the rendering list according to a preset time interval; and rendering and displaying the read data in the drawing.

Further, the method further comprises: calculating the geometric coordinates of the cells added into the cell queue, and storing the geometric coordinates in a red-black tree data structure; obtaining the cell adjacent to the target cell to join the cell queue comprises: obtaining the cell adjacent to the target cell to obtain a first cell, calculating the geometric coordinate of the first cell, and searching the geometric coordinate of the first cell in the red and black tree data structure; and when the first cell is not searched, adding the first cell into the cell queue.

Further, the shape of the cell is square, and acquiring the cell adjacent to the target cell includes: and acquiring the cells adjacent to the target cell in the left, upper right, lower left and lower directions.

In another aspect, the present invention provides an apparatus for authenticating a face region in a drawing sheet.

The device for identifying the face area in the drawing comprises the following steps: the reading module is used for reading the cells in the cell queue to obtain target cells, wherein the cells are areas with preset sizes and shapes, and the initial cells generated in the area to be identified in the drawing are used as the first cells in the cell queue; the detection module is used for detecting whether the target cell has an intersecting line or not; the processing module is used for determining the intersecting line as a key line when the target cell has the intersecting line, and acquiring the cell adjacent to the target cell in the drawing and adding the cell into the cell queue when the target cell does not have the intersecting line; and the identification module is used for searching polygons according to all the key lines when the cell queues are emptied so as to identify the area.

To achieve the above object, the present invention also provides a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the steps of the above method when executing the computer program.

To achieve the above object, the present invention also provides a computer-readable storage medium having stored thereon a computer program which, when being executed by a processor, carries out the steps of the above method.

According to the method, the device, the computer equipment and the storage medium for identifying the face area in the drawing, the area with the preset size and the preset shape is used as the cell, the cell queue is preset, the initial cell generated in the face area to be identified in the drawing is used as the first cell in the cell queue, and the cell formed by subsequent expansion and fission is also added into the cell queue. And aiming at the cell queue, reading each cell as a target cell, detecting whether an intersecting line exists in the target cell, if so, determining that the intersecting line is a key line, if not, continuing expanding fission of the target cell, namely, obtaining a cell adjacent to the target cell in a drawing and adding the cell to the cell queue, and when all the cells can not be fissured again and the cell queue is emptied finally, searching polygons according to all the key lines, wherein the searched polygons also can be identified as a face area. According to the invention, before polygon search is carried out, lines in a drawing are screened based on a flooding principle, and only lines intersected with cells simulating water drops are used as a search range, on one hand, along with continuous expansion and fission of the cells, the search range can be ensured to include side lines of a closed polygon, namely face area side lines, on the other hand, screening is completed when the cells can not be expanded and fission any more, and the search range is ensured not to include lines outside the closed polygon, so that polygon search is carried out in the search range, and the search efficiency and the search accuracy can be improved.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a flowchart of a method for identifying a face region in a drawing according to an embodiment of the present invention;

FIGS. 2-4 are schematic diagrams of cell expansion fission provided by an embodiment of the present invention;

FIG. 5 is a diagram illustrating a tree data structure according to an embodiment of the present invention;

FIG. 6 is a flowchart of a method for identifying a face region in a drawing according to a second embodiment of the present invention;

FIG. 7 is a diagram illustrating the effect of cell filling according to an embodiment of the present invention;

FIG. 8 is a block diagram of an apparatus for identifying a face region in a drawing according to a third embodiment of the present invention;

fig. 9 is a hardware configuration diagram of a computer device according to a fourth embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to improve the recognition efficiency of irregular surface areas in complex drawings, the inventor carries out the following research: if the face area is taken as a water overflowing area, the water flow boundary in the water overflowing area is found, namely the side line of the face area is found, and face area identification is completed. Therefore, the cells are preset to simulate water drops, the first cell in the drawing is simulated as a flood starting point, the process of expanding and splitting the first cell outwards continuously is simulated as a flood process, in the process, if a certain cell is intersected with a line, the water drops simulated by the cell meet obstacles, if the cell is not intersected with the line, the water drops simulated by the cell can continue to spread, therefore, the cell is expanded and split outwards continuously until no cell can continue to expand outwards, namely, no water drop can spread again, at the moment, the water drops are shown to cover the whole flood area in a spreading way, all obstacles colliding with the water drops necessarily comprise water flow boundaries, other obstacles outside the water flow boundaries are necessarily not included, namely, the line intersected with the cell necessarily comprises side lines of a surface area, and also necessarily does not comprise side lines outside the surface area, therefore, the area can be accurately and quickly obtained by searching polygons in the lines intersected with the cells.

Based on the research, the invention provides a method, a device, computer equipment and a storage medium for identifying a face area in a drawing, the method for identifying the face area in the drawing comprises the steps of setting a cell queue, taking an initial cell generated in the face area to be identified in the drawing as a first cell in the cell queue, reading a cell in the cell queue as a target cell, detecting whether an intersecting line exists in the target cell, if the intersecting line exists, determining that the intersecting line is a key line, if the intersecting line does not exist, acquiring a cell adjacent to the target cell in the drawing, adding the cell adjacent to the target cell into the cell queue, namely expanding and splitting the target cell, adding the cell obtained after splitting into the cell queue, and detecting the intersecting line by continuously reading the cell in the cell queue, and determining the key lines or continuing to expand and split until no cells capable of continuing to expand and split exist in the area, emptying the cell queue, and performing polygon search according to all the key lines to identify the area. When polygon searching is carried out, on one hand, compared with the prior art that all lines in a drawing are used as a searching range for searching, all key lines are used as the searching range to eliminate lines outside a surface area, so that the searching range is reduced, and the searching efficiency can be improved; on the other hand, all the key lines are used as the search range, the face area sidelines can be guaranteed to be included in the search range, the interference of the non-face area sidelines on the search result is reduced, and therefore the accuracy of the search is improved.

Specific embodiments of a method, an apparatus, a computer device, and a storage medium for identifying a face area in a drawing according to the present invention will be described in detail below.

Example one

The first embodiment of the present invention provides a method for identifying a face area in a drawing, which can improve the efficiency and accuracy of identifying an irregular face area in the drawing, and specifically, fig. 1 is a flowchart of the method for identifying a face area in a drawing according to the first embodiment of the present invention, and as shown in fig. 1, the method for identifying a face area in a drawing according to the first embodiment of the present invention includes the following steps S101 to S105.

Step S101: and reading the cells in the cell queue to obtain the target cells.

The unit grid is an area with preset size and shape, and an initial unit grid generated in a face area to be identified in the drawing is used as a first unit grid in the unit grid queue.

Specifically, an area is defined as a cell in accordance with a preset size and shape for simulating a water droplet. The size of the unit cell can be a preset constant, and can also be determined according to the parameters of the drawing. The shape of the unit grid can be irregular figure, and can also be regular figure such as circle, triangle, rectangle or square. Specifically, the geometric meaning of the cell size characterization is different according to the cell shape, for example, when the cell is a circle, the cell size characterizes the diameter size of the cell, and when the cell is a square, the cell size characterizes the side length size of the cell.

And aiming at a face area to be identified in a drawing, generating a unit cell as an initial unit cell at any position in the face area to be identified according to the preset size and shape, taking the initial unit cell as a starting point for simulating the overflowing water, and adding the initial unit cell into a unit cell queue to be used as a first unit cell in the unit cell queue. For example, the position where the user clicks in the surface domain to be recognized is obtained, and the initial cell is generated at the position.

After the cell is added to the cell queue, in step S101, the cell in the cell queue is read as a target cell. After each cell is read from the cell queue, it is deleted from the cell queue.

Step S102: and detecting whether the target cell has an intersecting line or not.

Step S103: and if the target cell has the intersecting line, determining the intersecting line as a key line.

Step S104: and if the target cell has no intersecting line, acquiring a cell adjacent to the target cell and adding the cell into the cell queue.

And detecting whether a line intersected with each target cell exists in the drawing or not for each target cell, and if so, marking the line intersected with the target cell as a key line. And if the target cell does not exist, performing expansion fission on the target cell, namely starting from the target cell, expanding the target cell to the periphery, acquiring the cell adjacent to the target cell, and adding the cell into the cell queue.

Optionally, the multithreading work mode is started, different cells are respectively obtained from the cell queue to serve as target cells to carry out detection and processing on the intersection lines until no cell can continue to expand and fission, and all cells in the cell queue can be emptied finally.

Step S105: and when the cell queue is emptied, carrying out polygon search according to all the key lines so as to identify the area.

The method is characterized in that the water overflowing process is simulated by adopting a cell expansion fission mode, intersection detection is carried out on each newly generated cell and a line in a drawing in the process, if the intersection line exists, the cell cannot be continuously fissured, therefore, when no cell capable of continuously fissuring exists, filling of cells in a face area is completed, and therefore the confirmation of the face area range is that no cell capable of continuously fissuring exists, namely a cell queue is emptied as a termination point.

When the cell queue is emptied, polygon searching is carried out by taking all the key lines as a searching range, and the searched polygons are also identified as surface areas. Specifically, any key line can be used as a reference line segment, depth traversal is performed forwards and backwards, intersecting line segments within a certain error range are searched, a closed polygon is finally generated, and face area identification is completed.

In the method for identifying a face area in a drawing provided in this embodiment, an area with a preset size and shape is used as a cell, a cell queue is preset, an initial cell generated in the face area to be identified in the drawing is used as a first cell in the cell queue, and a cell formed by subsequent expansion fission is also added to the cell queue. And aiming at the cell queue, reading each cell as a target cell, detecting whether an intersecting line exists in the target cell, if so, determining that the intersecting line is a key line, if not, continuing expanding fission of the target cell, namely, obtaining a cell adjacent to the target cell in a drawing and adding the cell to the cell queue, and when all the cells can not be fissured again and the cell queue is emptied finally, searching polygons according to all the key lines, wherein the searched polygons also can be identified as a face area. By adopting the method for identifying the face area in the drawing, before the polygon search is carried out, the lines in the drawing are screened based on the water overflow principle, and only the lines intersected with the cells of the simulated water drops are used as the search range.

Optionally, in an embodiment, generating the initial cell in the area to be identified in the drawing includes: acquiring the proportion of the drawing; determining the size of the unit cell according to the proportion; determining the position of the initial cell in the area to be identified in the drawing according to user operation; and generating the initial cell according to the size of the cell and the position of the initial cell.

Specifically, in this embodiment, the size of the unit cell is determined according to the scale of the drawing, and the size and the shape of all the unit cells are the same. For example, the drawing proportion is obtained by performing character recognition at a predetermined position where the drawing proportion is set in the drawing, or the attribute information of the drawing is read and analyzed to obtain the drawing proportion therein. The size of the unit cell influences the searching speed and the searching correctness, wherein the larger the size of the unit cell is, the faster the searching speed is, but the lower the searching correctness is, the smaller the size of the unit cell is, the slower the searching speed is, but the higher the searching correctness is, on the basis, the size of the unit cell is determined according to the drawing proportion, the larger the drawing proportion is, the larger the size of the unit cell is, the size of the unit cell is monotonically increased along with the drawing proportion, and therefore the balance between the searching efficiency and the searching correctness can be achieved. A size factor may be preset, the cell size being the product of the drawing scale and the size factor, for example, a size factor of 0.25, drawing scale 1:1000, and then the cell size is 250 mm. In addition, after the size of the unit cell reaches the minimum pitch of the lines in the drawing, the search speed may be further slowed down as the size of the unit cell decreases, but the search accuracy does not change any more, based on which the minimum size of the unit cell may be defined as the minimum pitch of the lines in the drawing, and when the size of the unit cell determined according to the drawing scale is smaller than the minimum size, the size of the unit cell is determined as the minimum size, for example, the minimum size of the unit cell is limited to 50 mm.

In order to determine the cell size, the following explains how the initial position of the cell is determined. When a user needs to identify a face area in a drawing, a click operation can be performed in the face area to be identified, and the position of an initial cell is determined according to the click position of the click operation, for example, the position of the initial cell is determined by taking the click position as the geometric center or the gravity center of the initial cell. When the size and shape of the cell and the location of the initial cell are determined, the initial cell can be determined, and the initial location of the cell expansion fission is determined.

Optionally, in an embodiment, the cell is square, and acquiring the cell adjacent to the target cell includes: and acquiring the cells adjacent to the target cell in the left, upper right, lower left and lower directions.

Fig. 2 to 4 are schematic diagrams of cell expansion fission provided by an embodiment of the present invention, and specifically, as shown in fig. 2 to 4, the cells are set to be square to facilitate calculation in the cell expansion fission process, and when cell expansion fission is performed, that is, when a cell adjacent to a target cell is obtained, the cells adjacent to the target cell are obtained in 8 directions, namely left, upper right, lower left, and lower left, where fig. 2 to 3 show that new 8 cells are obtained after an initial cell is subjected to one fission. As shown in fig. 4, when the 8 cells are respectively split again as target cells, new 16 cells can be obtained.

By adopting the method for identifying the surface area in the drawing provided by the embodiment, the square is taken as the shape of the cell, the calculation in the expansion fission process of the cell is facilitated to be simplified, and meanwhile, the cell is expanded in all directions during the expansion fission, so that the surface area to be identified can be filled with the cell as much as possible, and the accuracy of the surface area to be identified is further improved.

Optionally, in an embodiment, the method further includes: storing the cells added into the cell queue into a rendering list; reading data in the rendering list according to a preset time interval; and rendering and displaying the read data in the drawing.

Specifically, in the process of cell detection and expansion, on one hand, cells added into a cell queue are simultaneously stored in a rendering list, and on the other hand, cell data in the rendering list is read at preset time intervals and rendered in a drawing.

By adopting the method for identifying the face area in the drawing, which is provided by the embodiment, the dynamic graph similar to the water overflowing process can be displayed in the drawing, the user can obtain the process of filling the cells from the graph in real time, and when the gap of the face area to be identified is not a closed polygon due to drawing errors, the position of the gap can be obtained from the process of filling the cells, so that the user can correct the gap in time.

Optionally, in an embodiment, the method further includes: calculating the geometric coordinates of the cells added into the cell queue, and storing the geometric coordinates in a red-black tree data structure; obtaining the cell adjacent to the target cell to join the cell queue comprises: obtaining the cell adjacent to the target cell to obtain a first cell, calculating the geometric coordinate of the first cell, and searching the geometric coordinate of the first cell in the red and black tree data structure; and when the first cell is not searched, adding the first cell into the cell queue.

Specifically, in the cell detection and expansion process, after each cell added to the cell queue is added to the cell queue, the geometric coordinates of each cell are calculated and stored in the red and black tree data structure, and details about the red and black tree data structure are not repeated, which belongs to common general knowledge in the prior art. After expanding and splitting to obtain a cell, before adding the cell into a cell queue, calculating the geometric coordinate of the cell (namely, a first cell), searching the geometric coordinate of the cell in a data structure of a red-black tree, and if the geometric coordinate is found, indicating that the cell queue already comprises the cell before and belongs to a repeated cell without processing the cell; if the search is not due, the cell is added to the cell queue.

By adopting the method for identifying the face area in the drawing provided by the embodiment, after the unit cells are added into the unit cell queue, the unit cells are stored in the red and black tree data structure in the form of geometric coordinates; before the cells are added into the cell queue, the geometric coordinates of the cells are inquired in the red and black tree structure so as to realize the duplicate checking processing of the cells, avoid the redundant processing in cell expansion and detection, improve the utilization efficiency of processing resources and further improve the search efficiency. Meanwhile, cells in the rendering list are not repeated, and the display effect of the dynamic graph is improved.

Optionally, in an embodiment, the method further includes: extracting all lines in the drawing, determining a bounding box of each line, and storing the corresponding relation between the lines and the bounding boxes thereof; detecting whether the target cell has the intersecting line or not comprises the following steps: and searching the bounding box intersected with the target cell to obtain a target bounding box, and detecting whether lines corresponding to the target cell and the target bounding box are intersected or not.

Specifically, before the area identification, all lines in the drawing can be extracted for storage, so that when whether intersecting lines exist in the detection target cell or not, the stored lines can be searched and calculated, and the processing speed is increased. Further, when the lines are stored, the corresponding relation between each line and the surrounding box of each line is stored, when the intersecting lines of the target cells are detected, the line surrounding box intersecting the target cells is detected firstly, the lines are filtered for the first time, and then whether the lines corresponding to the target cells and the surrounding boxes intersect or not is detected.

By adopting the method for identifying the surface area in the drawing, provided by the embodiment, through the filtration of the intersection relation between the cell and the bounding box, the cell does not need to be compared with all lines, the number of the lines compared with the cell is reduced, and the processing speed is improved.

Optionally, in an embodiment, the method further includes: after determining the bounding box of the line, the maximum point coordinates Nmax (x, y) and the minimum point coordinates Nmin (x, y) of the bounding box are stored in a four-quadrant based tree data structure.

Searching the bounding box intersected with the target cell to obtain a target bounding box comprises the following steps: calculating the maximum point coordinate Bmax (x, y) and the minimum point coordinate Bmin (x, y) of the target cell; comparing the maximum point coordinate Nmax (x, y) of the bounding box at the current node in the tree data structure with the minimum point coordinate Bmin (x, y) of the target cell; when Nmax.x > Bmin.x, and Nmax.y < Bmin.y, determining that the bounding box at the current node in the tree data structure is the target bounding box; comparing the minimum point coordinate Nmin (x, y) of the bounding box at the current node in the tree data structure with the maximum point coordinate Bmax (x, y) of the target cell; when Nmin.x < Bmax.x and Nmin.y > Bmax.y, determining that the next node is the node in the first quadrant of the current node in the tree-like data structure; when Nmin.x is less than Bmax.x and Nmin.y is less than Bmax.y, determining the next node as the node in the fourth quadrant of the current node in the tree-shaped data structure; when Nmin.x > Bmax.x and Nmin.y > Bmax.y, determining the next node as the node in the second quadrant of the current node in the tree-like data structure; when Nmin.x > Bmax.x and Nmin.y < Bmax.y, determining the next node as the node in the third quadrant of the current node in the tree data structure.

Specifically, the bounding box of the line refers to a minimum rectangle capable of bounding the line, the maximum point coordinate of the bounding box is the top left vertex coordinate of the rectangle, the minimum point coordinate of the bounding box is the bottom right vertex coordinate of the rectangle, and the bounding box intersecting the target cell is determined by comparing the maximum point coordinate of the bounding box, the minimum point coordinate of the bounding box, and the maximum point coordinate and the minimum point coordinate of the target cell. The tree-shaped data structure based on four quadrants is set, each node corresponds to one line bounding box, and the maximum point coordinate and the minimum point coordinate of each node are stored. When the tree-like data structure is formed, firstly, a bounding box of any line in the drawing is used as a root node of the tree-like data structure, then, a four-quadrant is formed by using the maximum point coordinate (or the minimum point coordinate) in the root node as an origin, a quadrant of the maximum point coordinate (or the minimum point coordinate) of a second line bounding box in the four-quadrant is determined, a child node of the root node in the determined quadrant is formed, and then, for each line, a node corresponding to the maximum point coordinate (or the minimum point coordinate) of the line bounding box is determined from the root node, so that the tree-like data structure shown in fig. 5 is formed. And storing the maximum point coordinates and the minimum point coordinates of all the line bounding boxes of the graph paper through a tree data structure. The maximum point coordinate of the bounding box is characterized by Nmax (x, y), the minimum point coordinate of the bounding box is characterized by Nmin (x, y), x is an abscissa, and y is an ordinate.

When finding a bounding box intersecting a target cell, the finding is performed through a tree data structure. Firstly, calculating the maximum point coordinate Bmax (x, y) and the minimum point coordinate Bmin (x, y) of a target cell, then, starting from a root node of a tree-shaped data structure, comparing the maximum point coordinate Nmax (x, y) of a bounding box at the current node in the tree-shaped data structure with the minimum point coordinate Bmin (x, y) of the target cell, and if Nmax.x > Bmin.x and Nmax.y < Bmin.y, determining that the bounding box at the current node is intersected with the target cell to be the target bounding box; and then, determining a next node according to the relation between the minimum point coordinate Nmin (x, y) of the bounding box at the current node and the maximum point coordinate Bmax (x, y) of the target cell, obtaining a new current node after determining the next node, and traversing by the new current node until the current node is traversed to the leaf node at the tail end of the tree-shaped data structure.

When the next node is determined according to the relation between the minimum point coordinate Nmin (x, y) of the bounding box at the current node and the maximum point coordinate Bmax (x, y) of the target cell:

when Nmin.x < Bmax.x and Nmin.y > Bmax.y, determining that the next node is the node in the first quadrant of the current node in the tree-like data structure;

when Nmin.x is less than Bmax.x and Nmin.y is less than Bmax.y, determining the next node as the node in the fourth quadrant of the current node in the tree-shaped data structure;

when Nmin.x > Bmax.x and Nmin.y > Bmax.y, determining the next node as the node in the second quadrant of the current node in the tree-like data structure;

when Nmin.x > Bmax.x and Nmin.y < Bmax.y, determining the next node as the node in the third quadrant of the current node in the tree data structure.

By adopting the method for identifying the surface area in the drawing, the bounding boxes of the lines in the drawing are stored in the four-quadrant-based tree-shaped data structure, and when the bounding boxes intersected with the target cell are searched, the bounding boxes are searched and compared through the tree-shaped data structure, and the comparison with all the bounding boxes is not needed, so that the number of the bounding boxes compared with the target cell can be reduced, the processing speed is further improved, and the key lines can be quickly searched.

Example two

The second embodiment of the invention provides a method for identifying a face area in a drawing, which takes the identification of the face area in a CAD drawing as an example, and the embodiment is described in detail as follows.

In the method, firstly, a drawing where a face area to be identified is located is processed to obtain all lines. Specifically, all CAD lines of the drawing are extracted and cached, various combination drawings and block drawings exist in the CAD drawing, the block drawing is formed by combining a plurality of descendant primitives and exists as a whole, all the descendant primitives are extracted through a recursive algorithm, and all the lines are obtained.

And then, caching the lines, specifically, caching the corresponding relationship between the lines and the bounding boxes thereof when the lines are cached, and meanwhile, storing the bounding boxes into a tree-like data structure based on four quadrants, wherein the tree-like data structure can refer to the relevant description above, and details are not repeated here.

The small square cells are used as water drops to simulate the water overflowing effect, the size of the cells can be determined according to 1/4 of the drawing proportion, if the drawing proportion is 1:1000, the size of the cells is 250mm (all the cells keep the same size), namely the side length of the positive direction is 250 mm.

And then acquiring a mouse click position of a user, generating a first cell by taking the mouse click position as a cell centerline point according to the specified cell shape and size, taking the first cell as the start of fission filling, and adding the first cell into a cell queue.

As shown in fig. 6, starting from the first cell, the remaining cells are generated by sequentially performing fission, each cell is fissionable into 8 new cells, which are respectively left, upper right, lower right, and lower left, the new cell generated by each fission can be used as an object of the next fission, during the fission and filling processes, each cell needs to perform collision detection with a CAD line, if there is an intersecting CAD line, the cell will not be fissured, and meanwhile, the line intersecting with the cell is saved, if there is no intersecting CAD line, the fission is performed until there is no cell that can continue to be fissured, that is, the face region range is completely filled by the cell, a polygon is searched in the saved intersecting line, and a face region is identified.

The multithreading working mode can be started, cell fission, CAD collision detection, data storage and writing and the like are realized, and each thread executes the following functions:

and respectively and continuously reading the cells from the cell queue, performing collision intersection, performing 1-to-8 fission on the cells needing to be fissured, adding the fissured new cells into the cell queue, and repeating circularly until the area range needing to be identified is completely filled.

Wherein, in order to ensure that all cells added into the cell queue after fission are new cells, all cells generated in the fission process need to be rearranged. Specifically, the rearrangement may be performed based on a red-black tree structure.

Meanwhile, the rearranged cells, that is, the cells that can be added to the cell queue, are cached in the rendering List1, the main thread needs to read the data in the List1 at a timing of 200ms to perform data rendering, so as to achieve the dynamic identification effect of flooding, and the filling effect is as shown in fig. 7.

In the fission filling process, all the collided CAD lines also need to be cached in the List2, when the flood filling is finished, the main thread receives notification, then reads all the CAD line data in the List2, and takes one of the CAD line data as a reference line segment to perform depth traversal forwards and backwards to search for an intersected line segment within a certain error range. Optionally, an interface for polygon search is preset, and the polygon search is implemented by calling the interface.

EXAMPLE III

Corresponding to the first embodiment and the second embodiment, a third embodiment of the present invention provides a device for identifying a face area in a drawing, and accordingly, reference may be made to the first embodiment and the second embodiment for details of technical features and corresponding technical effects, which are not described again in this embodiment. Fig. 8 is a block diagram of an apparatus for identifying a face area in a drawing according to a third embodiment of the present invention, as shown in fig. 8, the apparatus includes: a reading module 201, a detection module 202, a processing module 203 and an identification module 204.

The reading module 201 is configured to read a cell in a cell queue to obtain a target cell, where the cell is an area with a preset size and a preset shape, and an initial cell generated in a surface area to be identified in a drawing is used as a first cell in the cell queue; the detection module 202 is configured to detect whether an intersection line exists in the target cell; the processing module 203 is configured to determine, when there is an intersecting line in the target cell, that the intersecting line is a key line, and when there is no intersecting line in the target cell, obtain, in the drawing, the cell adjacent to the target cell and add the cell to the cell queue; and the identifying module 204 is configured to perform a polygon search according to all the key lines when the cell queue is emptied, so as to identify the area.

Optionally, in an embodiment, the apparatus further includes a generation module, configured to generate an initial cell in the area to be identified in the drawing, where the generation module includes: the acquisition unit is used for acquiring the proportion of the drawing; a first determining unit for determining the size of the cell according to the ratio; the second determining unit is used for determining the position of the initial cell in the area to be identified in the drawing according to user operation; and the generating unit is used for generating the initial cell according to the size of the cell and the position of the initial cell.

Optionally, in an embodiment, the apparatus further includes: the drawing processing device comprises an extraction module and a first storage module, wherein the extraction module is used for extracting all lines in the drawing and determining bounding boxes of all the lines; the detection module includes: the detection unit is used for detecting whether lines corresponding to the target cell and the target bounding box are intersected or not.

Optionally, in an embodiment, the apparatus further includes: a first storage module, configured to store maximum point coordinates Nmax (x, y) and minimum point coordinates Nmin (x, y) of the bounding box in a four-quadrant-based tree data structure after determining the bounding box of the line; when the searching unit searches the bounding box intersected with the target cell to obtain the target bounding box, the specific steps executed by the searching unit comprise: calculating the maximum point coordinate Bmax (x, y) and the minimum point coordinate Bmin (x, y) of the target cell; comparing the maximum point coordinate Nmax (x, y) of the bounding box at the current node in the tree data structure with the minimum point coordinate Bmin (x, y) of the target cell; when Nmax.x > Bmin.x, and Nmax.y < Bmin.y, determining that the bounding box at the current node in the tree data structure is the target bounding box; comparing the minimum point coordinate Nmin (x, y) of the bounding box at the current node in the tree data structure with the maximum point coordinate Bmax (x, y) of the target cell; when Nmin.x < Bmax.x and Nmin.y > Bmax.y, determining that the next node is the node in the first quadrant of the current node in the tree-like data structure; when Nmin.x is less than Bmax.x and Nmin.y is less than Bmax.y, determining the next node as the node in the fourth quadrant of the current node in the tree-shaped data structure; when Nmin.x > Bmax.x and Nmin.y > Bmax.y, determining the next node as the node in the second quadrant of the current node in the tree-like data structure; when Nmin.x > Bmax.x and Nmin.y < Bmax.y, determining the next node as the node in the third quadrant of the current node in the tree data structure.

Optionally, in an embodiment, the apparatus further includes: the third storage module is used for storing the cells added into the cell queue into a rendering list; the reading module is used for reading the data in the rendering list according to a preset time interval; and the rendering module is used for rendering and displaying the read data in the drawing.

Optionally, in an embodiment, the apparatus further includes: the calculation module is used for calculating the geometric coordinates of the cells added into the cell queue, and the fourth storage module is used for storing the geometric coordinates in a data structure of the red and black tree; when the processing module acquires the cell adjacent to the target cell and adds the cell into the cell queue, the specific steps executed by the processing module include: obtaining the cell adjacent to the target cell to obtain a first cell, calculating the geometric coordinate of the first cell, and searching the geometric coordinate of the first cell in the red and black tree data structure; and when the first cell is not searched, adding the first cell into the cell queue.

Optionally, in an embodiment, the cell is square, and when the processing module obtains a cell adjacent to the target cell, the specifically executed steps include: and acquiring the cells adjacent to the target cell in the left, upper right, lower left and lower directions.

Example four

The fourth embodiment further provides a computer device, such as a smart phone, a tablet computer, a notebook computer, a desktop computer, a rack server, a blade server, a tower server or a rack server (including an independent server or a server cluster composed of a plurality of servers) capable of executing programs, and the like. As shown in fig. 9, the computer device 01 of the present embodiment at least includes but is not limited to: a memory 011 and a processor 012, which are communicatively connected to each other via a system bus, as shown in fig. 9. It is noted that fig. 9 only shows the computer device 01 having the component memory 011 and the processor 012, but it is to be understood that not all of the shown components are required to be implemented, and that more or fewer components may be implemented instead.

In this embodiment, the memory 011 (i.e., a readable storage medium) includes a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc.), a Random Access Memory (RAM), a Static Random Access Memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, and the like. In some embodiments, the storage 011 can be an internal storage unit of the computer device 01, such as a hard disk or a memory of the computer device 01. In other embodiments, the memory 011 can also be an external storage device of the computer device 01, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), etc. provided on the computer device 01. Of course, the memory 011 can also include both internal and external memory units of the computer device 01. In this embodiment, the memory 011 is generally used to store an operating system installed in the computer apparatus 01 and various types of application software, such as program codes of the device for identifying a face area in a drawing in the third embodiment. Further, the memory 011 can also be used to temporarily store various kinds of data that have been output or are to be output.

The processor 012 may be a Central Processing Unit (CPU), a controller, a microcontroller, a microprocessor, or other data Processing chip in some embodiments. The processor 012 is generally used to control the overall operation of the computer device 01. In this embodiment, the processor 012 is configured to execute program codes stored in the memory 011 or process data, such as a method of identifying a face area in a drawing.

EXAMPLE five

The fifth embodiment further provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc.), a Random Access Memory (RAM), a Static Random Access Memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, a server, an App application store, etc., on which a computer program is stored, which when executed by a processor implements corresponding functions. The computer-readable storage medium of this embodiment is used to store an apparatus for identifying a face area in a drawing, and when executed by a processor, the apparatus implements the method for identifying a face area in a drawing according to the first embodiment.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A method for identifying a face region in a drawing, comprising:

reading cells in a cell queue to obtain a target cell, wherein the cell is an area with a preset size and a preset shape, and an initial cell generated in a face area to be identified in a drawing is used as a first cell in the cell queue;

detecting whether the target cell has an intersecting line or not;

if the target cell has an intersecting line, determining the intersecting line as a key line;

if the target cell does not have an intersecting line, the cell adjacent to the target cell is obtained from the drawing and added into the cell queue; and

and when the cell queue is emptied, performing polygon search according to all the key lines to identify the face area.

2. The method for identifying the area of the drawing according to claim 1, wherein the generating of the initial cell in the area of the drawing to be identified comprises:

acquiring the proportion of the drawing;

determining the size of the unit cell according to the proportion;

determining the position of the initial cell in the area to be identified in the drawing according to user operation;

and generating the initial cell according to the size of the cell and the position of the initial cell.

3. The method of identifying a face region in a drawing according to claim 1,

the method further comprises the following steps: extracting all lines in the drawing, determining a bounding box of each line, and storing the corresponding relation between the lines and the bounding boxes thereof;

detecting whether the target cell has the intersecting line or not comprises the following steps: and searching the bounding box intersected with the target cell to obtain a target bounding box, and detecting whether lines corresponding to the target cell and the target bounding box are intersected or not.

4. The method of identifying a face region in a drawing according to claim 3,

the method further comprises the following steps: after determining the bounding box of the line, storing maximum point coordinates Nmax (x, y) and minimum point coordinates Nmin (x, y) of the bounding box in a four-quadrant based tree data structure;

searching the bounding box intersected with the target cell to obtain a target bounding box comprises the following steps:

calculating the maximum point coordinate Bmax (x, y) and the minimum point coordinate Bmin (x, y) of the target cell;

comparing the maximum point coordinate Nmax (x, y) of the bounding box at the current node in the tree data structure with the minimum point coordinate Bmin (x, y) of the target cell;

when Nmax.x > Bmin.x, and Nmax.y < Bmin.y, determining that the bounding box at the current node in the tree data structure is the target bounding box;

comparing the minimum point coordinate Nmin (x, y) of the bounding box at the current node in the tree data structure with the maximum point coordinate Bmax (x, y) of the target cell;

5. The method of identifying a territory in a drawing according to claim 1, further comprising:

storing the cells added into the cell queue into a rendering list;

reading data in the rendering list according to a preset time interval; and

rendering and displaying the read data in the drawing.

6. The method of identifying a face region in a drawing according to claim 1 or 5,

the method further comprises the following steps: calculating the geometric coordinates of the cells added into the cell queue, and storing the geometric coordinates in a red-black tree data structure;

obtaining the cell adjacent to the target cell to join the cell queue comprises: obtaining the cell adjacent to the target cell to obtain a first cell, calculating the geometric coordinate of the first cell, and searching the geometric coordinate of the first cell in the red and black tree data structure; and when the first cell is not searched, adding the first cell into the cell queue.

7. The method for identifying the face area in the drawing according to claim 1, wherein the cell is square in shape, and the obtaining of the cell adjacent to the target cell comprises:

and acquiring the cells adjacent to the target cell in the left, upper right, lower left and lower directions.

8. An apparatus for identifying a face region in a drawing, comprising:

the reading module is used for reading the cells in the cell queue to obtain target cells, wherein the cells are areas with preset sizes and shapes, and the initial cells generated in the area to be identified in the drawing are used as the first cells in the cell queue;

the detection module is used for detecting whether the target cell has an intersecting line or not;

the processing module is used for determining the intersecting line as a key line when the target cell has the intersecting line, and acquiring the cell adjacent to the target cell in the drawing and adding the cell into the cell queue when the target cell does not have the intersecting line; and

and the identification module is used for searching polygons according to all the key lines when the cell queue is emptied so as to identify the area.

9. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the steps of the method of any of claims 1 to 7 are implemented by the processor when executing the computer program.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that: the computer program when executed by a processor implements the steps of the method of any one of claims 1 to 7.