Page 18 - 中国仿真学会通讯2020第1期
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    We merge the facade model and the roof                             Figure 8: Modeling Results.
model and clip unnecessary polygons, leading to
the final model ( Figure 4( s) ) . Then we use the   that meets the assumptions of the Manhattan world
quadrilateral patch ( including two triangular       .On the one hand, the accuracy of building roof
patches) as the basic unit to reconstruct the        and facade models can be guaranteed by the
texture model of the building by projecting and      facade modeling method based on hierarchical
interpolating the original point cloud. Then the     reconstruction and the roof modeling method
realistic 3d model of the building can be obtained   based on block reconstruction. On the other hand,
through texture mapping. The result is shown in      using the color information of the original point
Figure 4( t) .                                       cloud for texture mapping can maximize the visual
                                                     effect of the appearance of the building model. By
4  Results                                           comparing the 3D building model built by Smart
                                                     3D and the method we proposed, we can know
      Figure 7 shows the comparison between the      that our method can greatly improve the surface
3D building model built by the method we             effect of the building geometric model on the basis
proposed and the commercial modeling software        of satisfying certain texture resolution. In
( Smart 3D) . Among them, Figure 7 ( a) shows        summary, the method proposed in this paper is
the 3D building white⁃mode model built by Smart      practical.
3D, and Figure 7 ( b) shows the building model
after texture mapping built by Smart 3D. Figure 7    5  Conclusions
( c ) shows the 3D building white⁃mode model
built by the method proposed in this paper. The            In this paper, an automatic method for large⁃
building model after texturemapping built by the     scale threedimensional building modeling is
method in this paper is given in Figure 7( d) .      proposed for the point cloud generated by aerial
                                                     oblique photogrammetry or LIDAR equipment. By
     Figure 7: Comparing the Method with Smart 3D.   extracting the roof and the facade from the point
                                                     cloud. the two parts are separately reconstructed.
      The 3D building model in the scene             On the basis of ensuring the integrity of the three⁃
established by the method proposed in this paper     dimensional building model, it can also improve
is shown in Figure 8.                                the details of the three⁃dimensional building
                                                     model to a certain extent. Compared with the
      It can be seen from the modeling results that  commercial modeling software, the model
the method proposed in this paper can                established by the method proposed in this paper
automatically model the 3D building point cloud
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