Fusion display method of GIS, DEM and BIM

Abstract

The present invention discloses a method for the fusion display of GIS, DEM, and BIM, which splits the fusion display of GIS image maps, DEM digital elevation models, and BIM models into color fusion display of GIS image maps and BIM models, and shape fusion display of DEM digital elevation models and BIM models. By inserting a transitional custom image layer, the color fusion display is converted into color fusion of GIS image maps and custom image layers, and color fusion of custom image layers and BIM models; an 8-pixel neighborhood ladder processing method is used to achieve shape fusion display of BIM model nesting and DEM digital elevation models. The advantages of the present invention are that it solves the problem of color fusion display of the two models and overcomes the problems of large gaps at the edges of the fusion display, large calculation amount, and display holes in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of GIS, DEM, and BIM fusion display, and in particular to a GIS, DEM, and BIM fusion display method. Background Art

[0002] GIS image maps used in geographic information systems, including satellite imagery from ArcGis, AutoNavi, and Baidu, can provide a macroscopic view of the two-dimensional geographic environment. Digital elevation models (DEMs) digitally simulate the terrain through an ordered array of numerical values, forming a ground model representing ground elevation. The fusion of GIS image maps and DEMs can provide a macroscopic view of the three-dimensional geographic environment, enabling various geospatial queries and spatial analyses. Building Information Modeling (BIM) is a three-dimensional engineering model primarily for individual structures, containing rich design and construction information and a very fine model resolution.

[0003] The integration of GIS image maps, DEM digital elevation models, and BIM models now allows 3D GIS to move from the macro to the micro, from the outdoor to the indoor, while also enabling integrated and refined indoor and outdoor management. The integration of GIS image maps, DEM digital elevation models, and BIM models involves two aspects: data fusion and integrated display. Data fusion standardizes the data information of different models, while display requires solving the problem of visually integrating different models. This primarily involves the color fusion display of GIS image maps and BIM models, as well as the fusion display of the 3D shapes of the DEM digital elevation models and BIM models (i.e., the two models).

[0004] Currently, the commonly used fusion display methods include plane overlay, fusion mosaic, and clear replacement. The plane overlay method is only suitable for flat terrain. For areas with significant undulations, it often forcibly flattens the terrain and then places the BIM model on the flattened surface, resulting in vertical sections of the terrain when displayed. Furthermore, because the edge of the BIM model is higher than the terrain, or the terrain is higher than the BIM model, a large gap will appear at the edge of the BIM model and the terrain.

[0005] The clear and replace method is to cut out the part of the terrain where the BIM model is to be displayed, and place the BIM model in the cut-out area. This method also has the same problem as the plane overlay method at the edge of the fusion. In addition, since GIS data is loaded and rendered progressively, a hole will appear when the perspective is just switched to the display area. As the BIM model is loaded, the BIM model will slowly appear in the hole.

[0006] The fusion mosaic method is similar to the clear-replace method, but it replaces low-precision terrain data with a high-precision BIM model. Therefore, it avoids the voids seen in the clear-replace method. However, the real-time fusion edge detection and terrain area segmentation process of replacing the BIM model consumes a large amount of CPU computing resources, causing rendering lags. Furthermore, this method still suffers from the problem of large gaps between the BIM model and the terrain.

[0007] At the same time, the above three methods can only solve the problem of three-dimensional shape fusion display, and do not involve the problem of color fusion display. Summary of the Invention

[0008] The present invention aims to provide a method for displaying the integration of GIS, DEM and BIM.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] The GIS, DEM, and BIM fusion display method of the present invention divides the fusion display of GIS image maps, DEM digital elevation models, and BIM models into color fusion display of GIS image maps and BIM models, and shape fusion display of DEM digital elevation models and BIM models.

[0011] The color fusion display is to insert a transitional custom image layer between the GIS image map and the BIM model, and convert the color fusion display into the color fusion of the GIS image map and the custom image layer and the color fusion of the custom image layer and the BIM model;

[0012] The shape fusion display is to set grid sampling points and gravity attributes above the BIM model, make the sampling points fall to the surface of the BIM model, extract the edge data of the BIM model, and extract the corresponding terrain data in the DEM digital elevation model based on the edge data; use the 8-pixel neighborhood ladder processing method to achieve the shape fusion display of the BIM model nesting and the DEM digital elevation model.

[0013] Furthermore, before the fusion display, the GIS image map and BIM model data are converted into a unified coordinate system.

[0014] Furthermore, the color fusion display specifically includes the following steps:

[0015] S1.1, taking the latitude and longitude of the BIM model on the earth as the center point, according to business needs, obtain a set of the custom images within a certain range in the GIS image map and construct a custom image layer;

[0016] S1.2. Adjust the viewing angle in the rendering software to be directly above the BIM model to obtain a projected image of the BIM model.

[0017] S1.3. Place the custom image layer and the projected image of the BIM model into image processing software. While ensuring edge fusion between the custom image layer and the GIS image map, modify the color of the projected image of the BIM model in the custom image layer and increase the resolution of the custom image layer.

[0018] S1.4, separately storing the component colors that need to be modified in the BIM model, and modifying the component colors when loading and rendering the BIM model.

[0019] Furthermore, each image in the custom image layer set is marked with corresponding longitude and latitude.

[0020] Furthermore, the shape fusion display specifically includes the following steps:

[0021] S2.1, obtain DEM digital elevation model data in TIF format;

[0022] S2.2. In the rendering software, set grid sampling points above the BIM model and set gravity attributes for the grid sampling points so that the grid sampling points fall to the surface of the BIM model and extract the edge data of the BIM model;

[0023] S2.3, determining a latitude and longitude bounding box of the BIM model based on the edge data, and extracting DEM digital elevation model data corresponding to the bounding box;

[0024] S2.4, traverse each pixel point in the DEM digital elevation model corresponding to the bounding box, and use an 8-pixel neighborhood ladder processing method to achieve shape fusion display of the BIM model nesting and the DEM digital elevation model.

[0025] Furthermore, the 8-pixel neighborhood ladder processing method is specifically as follows: if the 8 neighborhoods of the pixel point are all within the BIM model area, the height value corresponding to the pixel point is reduced to the lowest point in the BIM model; if part of the 8 neighborhoods of the pixel point is within the BIM model area, the DEM digital elevation model is trimmed in a manner of decreasing the pixel height value, so that the BIM geometric model is nested in the DEM digital elevation model.

[0026] Furthermore, the BIM model edge data is a series of closed curves consisting of discrete longitudes and latitudes.

[0027] The advantage of this invention lies in that, by inserting a transitional custom image layer, the color fusion display process is converted into the fusion of a GIS image map with a custom image layer, and then the fusion of the custom image layer with a BIM model. PS technology is used to solve the problem of color fusion display. The fusion of the DEM digital elevation model and the BIM model uses an 8-pixel neighborhood step-by-step processing method to embed the BIM model within the terrain, solving the problem of 3D shape fusion display and overcoming the problems of large gaps at the edges of the fusion display, high computational complexity, and display holes in the existing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the color fusion display flow chart of the present invention.

[0029] Figure 2 This is the shape fusion display flow chart of the present invention. DETAILED DESCRIPTION

[0030] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0031] The GIS image map, DEM digital elevation model, and BIM model involved in this invention each have their own characteristics. Although simply unifying the coordinate systems of the three to WGS84 can achieve their integration, they also face a series of problems such as inconsistent colors, mutual occlusion of data, large edge gaps, and difficulty in data updating.

[0032] The GIS, DEM, and BIM fusion display method described in the present invention splits the fusion of GIS image maps, DEM digital elevation models, and BIM models into two issues: color fusion display between the GIS image map and the BIM model, and shape fusion display between the DEM digital elevation model and the BIM model. Before fusion display, the GIS image map data and the BIM model data need to be converted to a unified coordinate system, which can be the WGS84 coordinate system. If the GIS image map is offset, it must be corrected first. At the same time, the BIM model must also undergo corresponding coordinate conversion and be placed in the corresponding position in the WGS84 coordinate system.

[0033] Color fusion display is to insert a transition custom image layer between the GIS image map and the BIM model, and convert the color fusion display into the color fusion of the GIS image map and the custom image layer and the color fusion of the custom image layer and the BIM model; specifically,

[0034] like Figure 1 As shown, the color fusion display includes the following steps:

[0035] S1.1. With the longitude and latitude of the BIM model on the earth as the center point, according to business needs, obtain the custom image set within a certain range in the GIS image map and construct a custom image layer; each image in the custom image layer is marked with the corresponding longitude and latitude.

[0036] S1.2. Adjust the viewing angle in the rendering software to be directly above the BIM model to obtain a projected image of the BIM model.

[0037] S1.3. Place the custom image layer and the projected image of the BIM model into the image processing software. While ensuring the edge fusion between the custom image layer and the GIS image map, modify the color of the BIM model projected image in the custom image layer and improve the resolution of the custom image layer.

[0038] S1.4, separately store the component colors that need to be modified in the BIM model, and modify the corresponding component colors when loading and rendering the BIM model.

[0039] When the shape fusion between the DEM digital elevation model and the BIM model is displayed, since the accuracy of the DEM digital elevation model is much lower than that of the BIM model, the DEM digital elevation model should be adjusted, and the DEM digital elevation model adjustment can be made during the rendering process, or the original terrain data can be adjusted. Considering that the GIS image map itself faces a large amount of various data when it is fused with the BIM model, if it is adjusted during the rendering process, a large amount of computing resources will be consumed, thereby affecting efficiency. Therefore, the present invention adopts a method of adjusting the original terrain. The original terrain data of the DEM digital elevation model is generally in TIF format, i.e., an image format. In this way, the adjustment of the DEM digital elevation model terrain data is an image processing process of the TIF format image.

[0040] Specifically, the shape fusion display between the DEM digital elevation model and the BIM model is to set grid sampling points and gravity attributes above the BIM model, so that the sampling points fall to the surface of the BIM model, and extract the edge data of the BIM model. Based on the edge data, the corresponding terrain data is extracted from the DEM digital elevation model; the 8-pixel neighborhood ladder processing method is used to achieve the shape fusion display of the BIM model nesting and the DEM digital elevation model. Specifically, the following steps are included:

[0041] like Figure 2As shown, S2.1 obtains DEM digital elevation model data in TIF format; DEM data can be divided into five types according to accuracy: 90m, 30m, 12.5m, and 5m. The corresponding terrain data can be selected according to business needs.

[0042] S2.2. In the rendering software, set grid sampling points above the BIM model and set gravity properties for the grid sampling points so that the grid sampling points fall to the surface of the BIM model and extract the BIM model edge data; the BIM model edge data is a series of closed curves composed of discrete longitudes and latitudes.

[0043] S2.3, based on the edge data, determine the latitude and longitude bounding box of the BIM model, and extract the DEM digital elevation model data corresponding to the bounding box;

[0044] S2.4, traverse each pixel point in the DEM digital elevation model corresponding to the bounding box, and use the 8-pixel neighborhood staircase processing method to realize the shape fusion display of BIM model nesting and DEM digital elevation model.

[0045] The specific method of 8-pixel neighborhood ladder processing is as follows: if the 8 neighborhoods of a pixel point are all within the BIM model area, the height value corresponding to the pixel point will be reduced to the lowest point in the BIM model. If part of the 8 neighborhoods of the pixel point is within the BIM model area, the DEM digital elevation model will be trimmed by decreasing the pixel height value so that the BIM geometric model is nested in the DEM digital elevation model.

Claims

1. A method for integrated display of GIS, DEM, and BIM, characterized by: The fusion display of GIS image map, DEM digital elevation model and BIM model is split into the color fusion display of GIS image map and BIM model, and the shape fusion display of DEM digital elevation model and BIM model; The color fusion display is to insert a transitional custom image layer between the GIS image map and the BIM model, converting the color fusion display into the color fusion of the GIS image map and the custom image layer, and the color fusion of the custom image layer and the BIM model; the custom image layer is a custom image collection within a certain range obtained in the GIS image map based on business needs, with the latitude and longitude of the BIM model on the earth as the center point; The shape fusion display is to set grid sampling points and gravity attributes above the BIM model, so that the grid sampling points fall to the surface of the BIM model, and extract the edge data of the BIM model. Based on the edge data, the corresponding terrain data is extracted from the DEM digital elevation model; the 8-pixel neighborhood ladder processing method is used to achieve the shape fusion display of the BIM model nesting and the DEM digital elevation model; The 8-pixel neighborhood ladder processing method is specifically as follows: if the 8 neighborhoods of the pixel point are all within the BIM model area, the height value corresponding to the pixel point is reduced to the lowest point in the BIM model. If part of the 8 neighborhoods of the pixel point is within the BIM model area, the DEM digital elevation model is trimmed in a pixel height value decreasing manner so that the BIM geometric model is nested in the DEM digital elevation model.

2. The GIS, DEM, and BIM integrated display method according to claim 1, characterized in that: Before the fusion display, the GIS image map and BIM model data are converted into a unified coordinate system.

3. The GIS, DEM, and BIM integrated display method according to claim 1, characterized in that: The color fusion display specifically includes the following steps: S1.1, taking the latitude and longitude of the BIM model on the earth as the center point, according to business needs, obtain the custom image set within a certain range in the GIS image map and construct a custom image layer; S1.

2. Adjust the viewing angle in the rendering software to be directly above the BIM model to obtain a projected image of the BIM model. S1.

3. Place the custom image layer and the projected image of the BIM model into image processing software. While ensuring edge fusion between the custom image layer and the GIS image map, modify the color of the projected image of the BIM model in the custom image layer and increase the resolution of the custom image layer. S1.4, separately storing the component colors that need to be modified in the BIM model, and modifying the component colors when loading and rendering the BIM model.

4. The method for integrated display of GIS, DEM, and BIM according to claim 3, characterized in that: Each image in the custom image layer is marked with corresponding longitude and latitude.

5. The GIS, DEM, and BIM integrated display method according to claim 1, characterized in that: The shape fusion display specifically includes the following steps: S2.1, obtain DEM digital elevation model data in TIF format; S2.

2. In the rendering software, set grid sampling points above the BIM model and set gravity attributes for the grid sampling points so that the grid sampling points fall to the surface of the BIM model and extract the edge data of the BIM model; S2.3, determining a latitude and longitude bounding box of the BIM model based on the edge data, and extracting DEM digital elevation model data corresponding to the bounding box; S2.4, traverse each pixel point in the DEM digital elevation model corresponding to the bounding box, and use an 8-pixel neighborhood ladder processing method to achieve shape fusion display of the BIM model nesting and the DEM digital elevation model.

6. The method for integrated display of GIS, DEM, and BIM according to claim 5, characterized in that: The BIM model edge data is a series of closed curves consisting of discrete longitudes and latitudes.

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