A center-point driven adaptive generation method for complex intersection morphology

Abstract

The present invention discloses a method for adaptively generating complex intersection morphologies driven by a center point, comprising the following steps: acquiring built environment data within a study scope, identifying all intersections of road centerlines within the study scope, and screening valid intersection points; radiating concentric circles from valid intersection points to obtain the minimum open space radius of the intersection, and calculating the empty radius representing the three-dimensional built environment surrounding the intersection in combination with the expansion coefficient; radiating circles with corresponding radii from all valid intersection points, cutting the ground contour data of the buildings within the circles, and stretching them in combination with the corresponding height information to form a model of the three-dimensional built environment surrounding the intersection. The present invention adopts an intelligent definition method to quickly and accurately define the three-dimensional built environment surrounding the intersection within the study scope, providing a comprehensive, rational, and scientific basis for the design, optimization, and improvement of the three-dimensional built environment surrounding the intersection.

Description

Technical Field

[0001] The present invention belongs to the field of smart city technology, and in particular relates to a method for adaptively generating complex intersection morphologies driven by a center point. Background Art

[0002] Urban intersections, also known as junctions or road intersections, often appear in the form of crossroads or T-junctions. They occur at the intersection of one road and other roads, and possess a wide variety of forms and types. In perceptual research, intersections can be viewed as "nodes" embedded in the urban public space network; in configurational analysis, they are considered turning points in continuous mileage and connection points in the street network; and in urban organizational analysis, intersections are considered to have a significant presence within the urban built environment. Intersections are crucial to the urban built environment. In today's world where national land space planning emphasizes high-quality development and refined governance, studying the three-dimensional built environment surrounding intersections has significant practical implications for urban intersection planning and construction. However, current research methods are limited to two-dimensional, flat studies, either ignoring intersection architecture, a core element of the three-dimensional form of urban intersections, or simply classifying them as part of the transportation sector. This approach also has certain limitations.

[0003] Existing demarcation methods primarily include those based on current urban traffic data and the central grid method. The former, based on current urban traffic data, utilizes detailed road traffic information, combined with the widths of different road types. Using this width as a reference, a specific range is defined with intersections as reference points. This approach provides a relatively accurate definition of the urban intersection's boundaries, offering a high degree of refinement. The latter, based on a GIS framework, primarily includes grid and buffer methods. Using the intersection as the geometric center, grid division is performed at a specific spatial scale, or concentric buffer zones of varying radii are created. This allows for a rough definition of the urban intersection's boundaries. It is efficient, convenient, and widely applicable. Both methods provide a rough estimate of the built environment surrounding an urban intersection. However, both methods have multiple problems: the method based on urban traffic status data has too high a data base requirement, and researchers find it difficult to obtain such information, so its application and efficiency are low; the spatial range generated by the central grid method is usually a geographic scale rather than a building scale, and almost all existing studies tend to use a unified scale to define the range of spatial units, such as 50m, 100m, etc. However, for public nodes such as urban intersections, different intersections in the city may have different scales, large or small, and of varying scales. These unified measurements of intersection ranges are still inaccurate representations of the form, which do not conform to the experience of urban planners and designers, and are also quite different from the public's perception of urban intersections.

[0004] In summary, in the definition of urban intersections, it is of great practical significance to adopt a convenient, efficient and accurate three-dimensional built environment measurement method around urban intersections and tailor the appropriate scope for different urban intersections. Summary of the Invention

[0005] To address the above-mentioned issues, the present invention discloses a center-point-driven adaptive generation method for complex intersection morphologies. This method uses an intelligent definition method to quickly and accurately define the three-dimensional built environment surrounding the intersection within the research scope, providing a comprehensive and rational scientific basis for the design, optimization, and improvement of the three-dimensional built environment surrounding the intersection.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A method for adaptively generating complex intersection morphology driven by a center point includes the following steps:

[0008] Step 1: Determine the research scope and obtain built environment data within the research scope;

[0009] Step 2: Identify all intersections in the road centerline layer and calculate the length of the polyline of the road centerline between any two adjacent intersections, denoted as l i and compare with the given length parameter L:

[0010] For any intersection, if the lengths of all the polylines of the road centerlines associated with it are l i ≥L, then the intersection is a valid intersection point;

[0011] If the length of the polyline of all the road center lines related to it exists l i <L, a new coordinate point is determined by generating a geometric center point as the valid intersection point at that location;

[0012] All valid intersection points obtained in the above two cases are numbered sequentially;

[0013] Step 3: For all valid intersection points, take their coordinates as the center and radiate concentric circles outward until they first come into contact with the bottom contours of the surrounding buildings. The radius of the concentric circles at this time is r. k , as the minimum open space radius of the intersection;

[0014] Step 4: Set the expansion coefficient β to represent the radius R of the 3D built environment around the intersection k and the minimum open space radius r k The relationship between R k The expression is:

[0015] R k =β×r k

[0016] Step 5: For all valid intersection points, take their coordinates as the center of the circle and use R k Draw a circle with the radius as the cutting radius, and the building bottom surface contour data within the cutting circle will be regarded as valid data;

[0017] Step 6: The building bottom surface outline, which is valid data, is highly stretched to form a three-dimensional built environment model around the intersection.

[0018] As a preferred embodiment of the present invention, step 1 adopts a combination of public data sets and field surveys to obtain built environment data within the research scope, wherein the public open source data sets come from OSM (OpenStreetMap) open source data, Baidu map open source data, Amap open source data, etc. The built environment data within the research scope is obtained to include at least three layers of information: road centerline, building bottom surface contour, and building height. Among them, the building bottom surface contour information category is a face element, and the building bottom surface contour and the building height form a one-to-one correspondence, that is, one building outer contour object corresponds to one building height data information, and the road centerline information category is a line element; at the same time, the initial elevation of the road centerline and the building bottom surface contour is 0, that is, they are in the same plane, and the building height refers to the vertical height value of the building;

[0019] As a preferred embodiment of the present invention, all the intersections identified in the road centerline layer in step 2 refer to geometric anchor points with a bifurcation number greater than 2. The information category of these geometric anchor points is point elements, and each geometric anchor point has a unique coordinate, which is recorded as (a i , b i );

[0020] As a preferred embodiment of the present invention, any two adjacent intersections in step 2 are any two adjacent points in the network system formed by the center lines of the roads;

[0021] As a preferred embodiment of the present invention, the steps of generating a geometric center point in step 2 to determine a new coordinate point as a valid intersection point at the location are as follows:

[0022] For the existence of i <L road centerline, judge whether the road centerline exists alone or continuously; alone means that other line segments connected to the road centerline are all l i ≥L; Continuous existence means that other line segments connected to the center line of this section of road still have l i <L situation;

[0023] If it exists alone, the coordinates of the two end points of the center line of the road section are (a i1 , b i1 ) and (ai2 , b i2 ), generate a new geometric center point 0 as the valid intersection point of the intersection, its coordinates are:

[0024]

[0025] If the road is continuous, the coordinates of the endpoints of the center lines of all roads involved in the continuous road are extracted and calculated as (a i1 , b i1 ), (a i2 , b i2 ),…,(a i(n-1) , b i(n-1) ), (a in , b in ), generate a new geometric center point as the effective intersection point of the intersection, its coordinates are:

[0026]

[0027] As a preferred embodiment of the present invention, the method of sequentially numbering all valid intersection points obtained in the above two situations in step 2 is generally to number the valid intersection points by natural numbers from large to small according to the ordinate values ​​of the valid intersection points to obtain a set of valid intersection point coordinates;

[0028] As a preferred embodiment of the present invention, in step 3, the following operations are performed on all valid intersection points in the order of their numbers: concentric circles are radiated outward from the coordinates of the valid intersection point as the center, and the concentric circles are surface elements until they first come into contact with the bottom surface outline of the surrounding buildings:

[0029] 1. Assuming the given distance accuracy is Δd, the radius r of the concentric circle is:

[0030] r=m·Δd(m=1,2,...,n);

[0031] 2. With the coordinates of the valid intersection point as the center, radiate concentric circles with a radius increasing by Δd. If there is no overlap with the bottom contours of the buildings around the intersection, the value of m is continuously increased by Δd.

[0032] 3. If the concentric circles do not overlap with the bottom contours of the buildings around the intersection when m = n-1, and do overlap with the bottom contours of the buildings around the intersection when m = n, then it is considered that the concentric circles and the bottom contours of the buildings around the intersection are in contact for the first time. The minimum open space radius at this time is:

[0033] r k =nΔd;

[0034] Finally, all valid intersection points and the minimum open space radius are obtained in one-to-one correspondence.

[0035] As a preferred embodiment of the present invention, the final value of the expansion coefficient β in step 4 is usually about 2, that is, the radius of the three-dimensional built environment around the intersection is considered to be roughly twice the radius of the minimum open space.

[0036] As a preferred embodiment of the present invention, the step of cutting the building bottom surface contour data within the circumference in step 5 includes:

[0037] 1. Investigate the area corresponding to the building outline around the effective intersection point and identify its relationship with the R k The spatial relationship of a circle with a radius of

[0038] 2. If the area falls completely within the circle, all its information is retained and the previous building height information is assigned to the building outline whose area falls completely within the circle;

[0039] 3. If the face area falls completely outside the circle, all its information is discarded;

[0040] 4. If part of the face region falls within the circle, retain the part that falls within the circle as a new object, and generate the corresponding building outline based on the new face region. Assign the previous building height information to the new building outline to form a corresponding relationship.

[0041] The beneficial effects of the present invention are:

[0042] (1) Wide adaptability: When faced with a research area with incomplete basic data, it is relatively easy to obtain operational basic data, so that the three-dimensional spatial model of the research street can be quickly collected. It has a wide range of applications and is easy to collect data on the research object.

[0043] (2) Strong adaptability: It can flexibly respond to streets of different sizes and shapes, improve the degree of automation of the demarcation process, avoid errors caused by human judgment or lack of experience in traditional methods, and reduce the impact of human intervention and subjective judgment.

[0044] (3) High intelligence: Through the automatic processing of floor plan information by algorithms, it can accurately identify and define reasonable street areas on a large scale, ensuring uniform standards in the collection process of urban streets of different scales and types, and enhancing the scientificity and rationality of urban street research. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a technical flow chart of a method for adaptively generating complex intersection morphology driven by a center point of the present invention;

[0046] Figure 2 is a certain intersection range map defined according to the method of the present invention;

[0047] Figure 3 It is the surface area diagram corresponding to the first contact between the concentric circles of the present invention and the bottom contour of the building;

[0048] Figure 4 It is a three-dimensional built environment map around a certain intersection created by using Sketchup software in the present invention, where h is the building height. DETAILED DESCRIPTION

[0049] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0050] As shown in the figure, the method for adaptively generating complex intersection morphology driven by a center point according to the present invention includes the following steps:

[0051] Step 1: Determine the research scope and obtain built environment data within the research scope;

[0052] Usually, a combination of public data sets and field surveys is used to obtain built environment data within the research scope. The sources of public open source data sets include OSM (OpenStreetMap) open source data, Baidu map open source data, and Amap open source data. Obtaining built environment data within the research scope includes at least three layers of information: road centerline, building bottom surface outline, and building height. Among them, the building bottom surface outline information category is a face element, and the building bottom surface outline and the building height form a one-to-one correspondence, that is, one building outer contour object corresponds to one building height data information, and the road centerline information category is a line element; at the same time, the initial elevation of the road centerline and the building bottom surface outline is 0, that is, they are in the same plane, and the building height refers to the vertical height value of the building;

[0053] Step 2:

[0054] 2-1 Identify all intersections in the road centerline layer and calculate the length of the polyline of the road centerline between any two adjacent intersections, denoted as l i and compare it with the given length parameter L;

[0055] Among them, all intersections in the road centerline layer are identified as geometric anchor points with a bifurcation number greater than 2. The information category of these geometric anchor points is point features. Each geometric anchor point has a unique coordinate, which is recorded as (a i , b i ); There are two geometric anchor points at the intersection of the present invention, namely M(a1, b1) and N(a2, b2), such as Figure 2 As shown;

[0056] 2-2 For any intersection, if the lengths of all the polylines of the road centerlines associated with it are li ≥L, then the intersection is a valid intersection point;

[0057] The arbitrary two adjacent intersections are any two adjacent points in the network system formed by the road centerline;

[0058] 2-3 If the length of the polyline of all the road center lines related to it exists l i <L, a new coordinate point is determined by generating a geometric center point as the valid intersection point at that location;

[0059] The steps of generating a geometric center point and determining a new coordinate point as a valid intersection point at the location are as follows:

[0060] 2-3-1 For the existence of l i <L road centerline, judge whether the road centerline exists alone or continuously; alone means that other polylines connected to the road centerline are all l i ≥L; Continuous existence means that there are still other polylines connected to the center line of this section of road. i <L situation;

[0061] 2-3-2 If it exists alone, the coordinates of the two end points of the center line of the road section are (a i1 , b i1 ) and (a i2 , b i2 ), generate a new geometric center point as the effective intersection point of the intersection, its coordinates are:

[0062]

[0063] 2-3-3 If the road is continuous, extract the coordinates of the endpoints of the center lines of all roads involved in the continuous road, and calculate it as (a i1 , b i1 ), (a i2 , b i2 ),…,(a i(n-1) , b i(n-1) ), (a in , b in ), generate a new geometric center point as the effective intersection point of the intersection, its coordinates are:

[0064]

[0065] The effective intersection point of the intersection in the present invention is point O, and its coordinates are

[0066] 2-4 For the above two cases, all valid intersection points are numbered in sequence. The general method is: number the valid intersection points by natural numbers from large to small according to the vertical coordinate values, and obtain a set of valid intersection point coordinates.

[0067] Step 3: For all valid intersection points, take their coordinates as the center and radiate concentric circles outward until they first come into contact with the bottom contours of the surrounding buildings. The radius of the concentric circles at this time is r. k , as the minimum open space radius of the intersection;

[0068] For all valid intersection points, perform the following operations in the order of their numbers: Radiate concentric circles outward from their coordinates as the center. The concentric circles are now surface features. The steps until they first come into contact with the bottom contours of the surrounding buildings are:

[0069] 3-1 Assuming the given distance accuracy is Δd, the value of the radius r of the concentric circle is:

[0070] r=m·Δd(m=1,2,...,n);

[0071] 3-2 With the coordinates of the effective intersection point as the center, radiate concentric circles with a radius increasing by Δd. If there is no overlap with the bottom contours of the buildings around the intersection, the value of m is continuously increased by Δd.

[0072] 3-3 If the concentric circles do not overlap with the bottom contours of the buildings around the intersection when m = n-1, and if the concentric circles do overlap with the bottom contours of the buildings around the intersection when m = n, it is considered that the concentric circles and the bottom contours of the buildings around the intersection have made contact for the first time.

[0073] 3-4 The minimum open space radius at this time is:

[0074] r k =nΔd;

[0075] 3-5 Finally, we get a one-to-one correspondence between all valid intersection points and the minimum open space radius.

[0076] Step 4: Set the expansion coefficient β to represent the radius R of the 3D built environment around the intersection k and the minimum open space radius r k The relationship between R k The expression is:

[0077] R k =β×r k .

[0078] The final value of the expansion coefficient β is usually around 2, which means that the radius of the three-dimensional built environment around the intersection is roughly twice the radius of the minimum open space.

[0079] Step 5: For all valid intersection points, take their coordinates as the center of the circle and use R k Draw a circle with the radius as the cutting radius, and the building bottom surface contour data within the cutting circle will be regarded as valid data;

[0080] The step of cutting the building bottom surface contour data within the circumference includes:

[0081] 5-1 Investigate the area corresponding to the bottom contour of the buildings around the effective intersection point and identify its intersection with R k The spatial relationship of a circle with a radius of

[0082] 5-2 If the area falls completely within the circle, all its information is retained and the previous building height information is assigned to the building outline whose area falls completely within the circle;

[0083] 5-3 If the face area falls completely outside the circle, all its information will be discarded;

[0084] 5-4 If part of the face region falls within the circle, the part falling within the circle is retained as a new object, and the corresponding building outline is generated based on the new face region. The previous building height information is assigned to the new building outline to form a corresponding relationship.

[0085] Step 6: The building bottom surface outline, which is valid data, is highly stretched to form a three-dimensional built environment model around the intersection.

[0086] It should be noted that the above content merely illustrates the technical idea of ​​the present invention and cannot be used to limit the scope of protection of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications all fall within the scope of protection of the claims of the present invention.

Claims

1. A center-point driven adaptive generation method for complex intersection morphology, characterized by: include Step 1: Determine the research scope and obtain built environment data within the research scope; Step 2: 2-1 Identify all intersections in the road centerline layer and calculate the length of the polyline of the road centerline between any two adjacent intersections, denoted as l i and compared with a given length parameter L: 2-2 For any intersection, if the lengths of all the polylines of the road centerlines associated with it are l i ≥L, then the intersection is a valid intersection point; If there exists l among the polyline lengths of all the road centerlines related to it i <L, a new coordinate point is determined by generating a geometric center point as the valid intersection point at this location; 2-4: Sequentially number all valid intersection points obtained in step 2-2 and step 2-3; Step 3: For all valid intersection points, take their coordinates as the center and radiate concentric circles outward until they first come into contact with the bottom contours of the surrounding buildings. The radius of the concentric circles at this time is r. k , as the minimum open space radius of the intersection; Step 4: Set the expansion coefficient β to represent the radius R of the 3D built environment around the intersection k and the minimum open space radius r k The relationship between R k The expression is: R k ＝β×r k Step 5: For all valid intersection points, take their coordinates as the center of the circle and use R k Draw a circle with the radius as the cutting radius, and the building bottom surface contour data within the cutting circle will be regarded as valid data; Step 6: The building bottom surface outline, which is valid data, is highly stretched to form a three-dimensional built environment model around the intersection.

2. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: The built environment data within the research scope obtained in step 1 includes information of at least three layers: road centerline, building bottom outline, and building height; the building bottom outline and the building height form a one-to-one correspondence, that is, one building bottom outline object corresponds to one building height data information; at the same time, the initial elevation of the road centerline and the building bottom outline is 0, that is, they are in the same plane.

3. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: In step 2-1, all intersections in the road centerline layer are identified as geometric anchor points with a bifurcation number greater than 2.

4. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: In step 2-2, the "arbitrary intersection" is any two adjacent points in the network system formed by the road centerline.

5. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: The steps of generating the geometric center point in step 2-3 and determining a new coordinate point as a valid intersection point at the location are as follows: 2-3-1 For the case where there is a road center line of l i <For the case of the road center line of L, determine whether this section of the road center line exists alone or continuously; existing alone means that the other multiple line segments connected to this section of the road center line all show l i ≥L; existing continuously means that there are still l among the other multiple line segments connected to this section of the road center line i <The case of <L; 2-3-2 If it exists alone, the coordinates of the two end points of the center line of the road section are (a i1 ,b i1 ) and (a i2 ,b i2 ), the coordinates of the generated geometric center point are: 2-3-3 If the road is continuous, extract the coordinates of the endpoints of the center lines of all roads involved in the continuous road, and calculate it as (a i1 ,b i1 ),(a i2 ,b i2 ),…,(a i(n-1) ,b i(n-1) ),(a in ,b in ), the coordinates of the generated geometric center point are:

6. The method for adaptively generating complex intersection shapes driven by a center point according to claim 1, characterized in that: The method of sequentially numbering all valid intersection points obtained in the above two situations in step 2-4 is: numbering the valid intersection points by natural numbers from large to small according to the vertical coordinate values.

7. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: In step 3, for all valid intersection points, the steps of radiating concentric circles outward with the coordinates of the intersection points as the center until the first contact with the bottom surface outline of the surrounding buildings is as follows: 3-1 Assuming the given distance accuracy is Δd, the value of the radius r of the concentric circle is: r=m·Δd(m=1,2,…,n); 3-2 With the coordinates of the effective intersection point as the center, the value of m increases continuously when radiating concentric circles outward; 3-3 If the concentric circles do not overlap with the bottom contours of the buildings around the intersection when m = n-1, and do overlap with the bottom contours of the buildings around the intersection when m = n, then it is considered that the concentric circles and the bottom contours of the buildings around the intersection have first contacted each other; 3-4 The minimum open space radius at this time is: r k =nΔd。 8. The method for adaptively generating complex intersection morphology driven by a center point according to claim 1, characterized in that: The expansion coefficient β in step 4 is set to 2.

9. The method for adaptively generating complex intersection shapes driven by a center point according to claim 1, characterized in that: The step of cutting the building bottom surface contour data within the circumference in step 5 includes: 5-1 Investigate the area corresponding to the bottom contour of the buildings around the effective intersection point and identify its intersection with R k The spatial relationship of a circle with a radius of 5-2 If the face area falls completely within the circle, all its information is retained; 5-3 If the face area falls completely outside the circle, all its information will be discarded; 5-4 If part of the face region falls within the circle, the part falling within the circle is retained as a new object, and the corresponding building outline is generated based on the new face region. The previous building height information is assigned to the new building outline to form a corresponding relationship.

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